Certificate of Sponsorship (CoS)

Key Takeaways

• A Certificate of Sponsorship is an electronic record held in the Sponsorship Management System, not a paper document and not a work permit. The worker needs only its reference number to apply, and assigning one does not guarantee that a visa will be granted.
• Defined CoS are only for Skilled Workers applying from outside the UK, and you apply for each one as you need it. Every other CoS is Undefined and comes from your annual allocation. Assigning an Undefined CoS where a Defined one is required is a ground on which the Home Office will normally revoke your licence.
• An allocation of Undefined CoS lasts for your CoS year and cannot be carried over. An A-rated sponsor on an eligible route, whose allocation is marked active, is renewed automatically at the number of CoS it actually assigned; everyone else makes a manual request, up to 3 months before the year ends.
• Watch the time limits. A Defined CoS must be assigned within 90 days of reaching your account, and any assigned CoS must be used within 3 months. The worker also cannot apply more than 3 months before the start date on the CoS.
• On the Skilled Worker route, no sponsor may ask a worker to pay for a CoS. The sponsor pays the fee, and passing it on to the worker is a ground on which the Home Office will normally revoke the licence. The same ban covers the Global Business Mobility, Minister of Religion, International Sportsperson, Scale-up and Seasonal Worker routes. Anyone who asks a Skilled Worker for money for a certificate is either running a scam or breaking the rules, and the answer in both cases is not to pay.
• No Defined CoS can be issued for a care worker (6135) or senior care worker (6136) role. A care job offered to someone overseas, with a certificate attached, cannot lead to a Skilled Worker visa.
• WorkPermitCloud helps sponsors manage certificates day to day, from allocation requests and Defined CoS applications to assigning, correcting and withdrawing them. See our sponsorship duties service.

Introduction

This page is for licensed sponsors and the Level 1 Users who assign certificates on their behalf, and for workers who want to check the certificate they have been given. It explains the two types of CoS, how allocations work, what must go on a certificate, the time limits that apply once it is assigned, and the checks that show whether a CoS is genuine. Getting a licence in the first place is covered in Sponsor Licence: How to Apply.

What a Certificate of Sponsorship Is

Every worker applying on a Worker or Temporary Worker route needs a valid Certificate of Sponsorship from a licensed sponsor. Despite the name, it is not a certificate in any physical sense. Part 2 of the sponsor guidance describes it as "a database record which confirms details of the worker you intend to sponsor and the job they will do". You create it by working through a short online form in your Sponsorship Management System (SMS) account, and everything you enter is stored where the Home Office can see it.

When you assign a CoS, you are confirming to the Home Office that you:

• wish to sponsor the worker
• are satisfied the worker can meet the immigration requirements of the route
• are eligible to sponsor the worker on that route
• agree to the terms and conditions set out in the SMS

A CoS is not a work permit. It lets the worker make an application, and the Home Office then decides whether to grant permission. Assigning one guarantees nothing, because the worker must still meet every requirement of the route. For a short introduction written for workers, see our short guide to the UK Certificate of Sponsorship.

Who Can Assign a CoS

A CoS can only be assigned by a Level 1 User, or by an existing Level 2 User while that role remains on the licence. Only a Level 1 User can apply for a Defined CoS. Who can hold these roles, and how to add or remove them, is covered in Sponsor Licence: SMS and Key Personnel. For a walk-through of the SMS screens, see our UK Sponsor Management System guide for employers.

Talk to the Worker First

Before you assign a certificate, find out the worker's current immigration status. Their existing route may not allow them to switch from inside the UK, in which case they will have to leave and apply for entry clearance from abroad. The route you are sponsoring them on may also have a maximum period that time already spent in the UK counts towards. If you do not follow the rules on assigning certificates, the Home Office can revoke, suspend or downgrade your licence, or reduce or remove the number of certificates you can assign.

Defined and Undefined CoS

There are two types of certificate, and on the Skilled Worker route the difference matters a great deal.

The common shorthand, that Defined CoS are for people outside the UK and Undefined CoS for people inside it, is only true on the Skilled Worker route. A Global Business Mobility worker, a Scale-up Worker or a Creative Worker applying from abroad is assigned an Undefined CoS.

When You Need a Defined CoS

If the Skilled Worker you want to sponsor will apply for entry clearance from outside the UK, you must apply for a Defined CoS and wait for it to be approved before you can assign it. You can apply once you have identified a particular worker for an eligible role, or before that, if you have an eligible role to fill and reasonably expect to need to sponsor someone who is not in the UK. You can ask for more than one in a single application, provided the start date, occupation code, job description and salary are the same on each.

Roles That Cannot Use a Defined CoS

Care workers and senior care workers. A Defined CoS cannot be issued under occupation code 6135 (care workers and home carers) or 6136 (senior care workers). A worker in either code can only be sponsored from inside the UK, and only where the additional requirements for care roles are met. The detail is in Care Worker and Health Routes.

Jobs below graduate level. Where a role is below graduate level and is not on the Immigration Salary List or the Temporary Shortage List, you can only apply for a Defined CoS under the transitional provision for skill level, and only once you have identified the worker. The job description field must confirm the worker meets the transitional provision and give their name, nationality and date of birth, any Home Office reference number you know, and their most recent CoS number if you know it. Which roles qualify is covered in Skilled Worker: Eligibility and Salary.

Getting the Type Wrong

The Home Office treats the choice of certificate type as a test of whether you understand the scheme. The sponsor guidance grades the same failures differently in different documents, so each is set out here as it is written:

• Part 2, paragraph S2.11, says the Home Office will normally revoke your licence if you assign a Defined CoS for a job other than the one described in the application for it, or an Undefined CoS where a Defined one is required.
• Part 3, Annex C2(u), lists assigning an Undefined Skilled Worker CoS to a worker who needs a Defined one as a ground on which it will normally revoke.
• Part 3, Annex C1(q), lists using a CoS to fill a role other than the one specified on the CoS, unless the change is permitted and you have notified the Home Office, as a ground on which it will revoke.
• Part 3, Annex C1(r), lists giving false information in any application for, or request to assign, a CoS as a ground on which it will revoke.
• Sponsor a Skilled Worker, paragraphs SK11.8 and SK12.2, say the Home Office is likely to revoke if you assign the wrong type, and SK11.8 says the same of false information on a Defined CoS application. Paragraph SK12.35 says it will revoke where it finds you gave false information in a Defined CoS application, and gives assigning the CoS for a job other than the one described in the application as an example.

The same failure can therefore be graded "will normally revoke" in one document, "likely to revoke" in another and "will revoke" in a third. All of these gradings appear in Home Office guidance, and this page does not choose between them.

Your CoS Allocation

Your allocation is the number of Undefined CoS you can assign during your CoS year. Defined CoS are never part of it.

How Your First Allocation Is Set

When you apply for a licence, you estimate how many Undefined CoS you will need in your first year on each route, and you must justify the number. The Home Office may ask for more information before deciding. In setting your allocation it may consider, among other things:

• any agents you will use to recruit, and whether they have been linked to immigration abuse
• your previous record with the Home Office, including under the old Tier 2 and Tier 5 scheme
• how many people you employ
• the kind of business you run, how much of it you do, and how long you have been trading
• on the UK Expansion Worker route, whether your Authorising Officer is based in the UK or overseas

You may be given fewer than you asked for, or none, if you have a history of non-compliance, your justification is weak, your need does not look credible, the Home Office is not satisfied you can offer work that meets the definition of an eligible role, or you are unsure whether or when you will need to recruit. The Home Office applies the same considerations to applications for Defined CoS. The application itself is covered in Sponsor Licence: How to Apply.

A sponsor on the UK Expansion Worker route with a Provisional rating can assign only one certificate, to its Authorising Officer. Once that person has their visa and the licence is upgraded to an A-rating, the sponsor can request up to 9 more.

Your CoS Year

Once your allocation is decided, the certificates are added to your SMS account and you have up to 12 months to use them. This is your CoS year, sometimes called your allocation year, and when it starts depends on the history of your licence:

• Converted Tier 2 licence, renewal automated. If you held a valid Tier 2 (General) or Tier 2 (Intra-Company Transfer) licence on 30 November 2020, it was converted on 1 December 2020, and your allocation renewal has been automated, your CoS year runs from 6 April to 5 April.
• Converted Tier 2 licence, renewal not automated. Your CoS year ran for 12 months from the date your renewal request was granted in 2021, and after that runs for 12 months from each renewal.
• Every other licence. Your CoS year runs for 12 months from the date the licence was granted, and after that for 12 months from each renewal.

Knowing when your year ends matters, because unused certificates are removed from your account at that point and cannot be carried over.

Asking for More CoS During the Year

If you think you will run out before the end of your CoS year, or your allocation was set to zero, you can ask for more through the SMS. You must give reasons and the Home Office may ask for evidence. A request for extra Undefined CoS is usually decided within 12 weeks, and it can take longer if the Home Office needs to make further checks. The steps are set out in guide 7 of the SMS manual on managing your licence.

Giving false information in any request for certificates is a ground on which the Home Office will revoke your licence.

Automatic and Manual Renewal

Your allocation must be renewed each year while your licence is valid. At the end of the CoS year you will either be renewed automatically or have to make a manual request, sometimes called a follow-on allocation.

You are renewed automatically if all of these are true:

• your licence is A-rated
• your current annual allocation is marked as active in your SMS account
• you are licensed on an eligible route

Every Worker and Temporary Worker route is eligible except Seasonal Worker, Secondment Worker, Service Supplier and UK Expansion Worker.

An automatic renewal gives you the number of certificates you assigned in the year just ending, not the number you were allocated. If you were allocated 15 and assigned 10, you are renewed at 10. If you need more, you make a request to increase it. Automatic renewal covers Undefined CoS only; Skilled Worker sponsors still apply for each Defined CoS as they need it.

If you do not qualify for automatic renewal, you submit a manual request through the SMS, which a caseworker considers. You can send it up to 3 months before the end of your CoS year. Giving false information in a renewal request is a ground on which the Home Office will revoke your licence.

The cost of letting an allocation run out is practical rather than financial: until a new allocation is granted, you have no Undefined CoS to assign, and that can hold up extensions for workers you already employ. For more on the reminders sponsors receive and what to do with them, see our post on annual CoS allocations.

The Priority Service

If you need an allocation request considered quickly, you can use the Home Office's priority change of circumstance service. It covers requests for an additional CoS allocation and for an annual allocation, alongside some other changes to your licence.

• You must be an A-rated, fully active Worker or Temporary Worker sponsor, and you must first submit the request through the SMS. It cannot already be in progress or allocated to a caseworker.
• Post-licence requests on the UK Expansion Worker, Service Supplier and Secondment Worker routes are not accepted.
• It costs £350 per request, and requests are only taken between 7am and 5pm, Monday to Friday.
• Eligible requests are considered within 5 working days, counted from the working day after you pay. A complex request, or one needing extra checks, can take longer, and the service does not guarantee approval.
• It does not take Defined CoS requests. Any Defined CoS request sent through it will be rejected, and the fee will not be refunded.
• A minimum of 120 priority requests are accepted each day.
• You request it by email to postlicencepriorityservice@homeoffice.gov.uk, with the completed request form and your organisation's name, sponsor licence number and request type in the subject line. You then have 72 hours from the second email you receive to pay.

The priority fee is one of the costs you must not pass on to a worker (see What a CoS Costs below).

When an Allocation Is Reduced

The Home Office may reduce your allocation, or set it to zero, if your circumstances change: for example, if you downsize, or if it takes compliance action against you after the allocation was set. A B-rated sponsor can only assign certificates to extend the permission of workers it already sponsors, and a licence reinstated with a B-rating after suspension may have its allocation reduced or set to zero. Ratings and action plans are covered in Sponsor Licence: Suspension and Revocation.

Applying for a Defined CoS

A Level 1 User applies for a Defined CoS through the SMS. Every mandatory field, marked with an asterisk, must be completed before the application can be sent, and the information about the role is the same as you would give for an Undefined Skilled Worker CoS. The screens are explained in SMS guide 12.

Salary and Hours on the Application

The salary must be a genuine reflection of what you intend to pay, must be eligible for 20 points for salary, and must meet every salary requirement of the Skilled Worker route. If it does not, the application is rejected.

• Where you have identified the worker, say in the "Summary of job description" field which salary points option they will claim, and briefly explain how they meet it. If they will claim points as a new entrant on the basis of their age, include their name, date of birth and nationality.
• Where you have not identified a worker yet, you must still give this information, but you cannot assume the eventual worker will qualify under one of the more favourable options unless you can justify it: for example, that the job requires a relevant PhD, is on the Immigration Salary List, or is in an occupation or regulated profession that fits the new entrant options. Without a satisfactory justification, the salary must qualify under Option A or Option K.
• Hours. State the weekly hours. If the pattern varies, describe it. If hours are still being agreed, give the hours you would normally expect in a similar role, explain this, and confirm the correct figure with a sponsor note when you assign the CoS.

What counts as salary, and the points options themselves, are covered in Skilled Worker: Eligibility and Salary.

If the worker will work on a client contract, give the client's name and business address, the length of the contract and its key deliverables in the "Summary of client contract" field.

How the Home Office Decides

A straightforward application is normally decided within one working day. The Home Office may check it first, for example if it doubts that the role meets the Skilled Worker requirements, and it may ask you for information or documents. If you do not send them within the time given, the application is rejected.

It will reject the application if it has reasonable grounds to believe that:

• the job does not meet the skill level requirement, including the occupation code or ATAS requirement
• you are relying on a transitional provision but have not identified the worker, or the worker does not meet it
• you have chosen an inappropriate occupation code
• the job does not meet the salary requirements
• the job is not genuine, or amounts to hiring the worker out to a third party
• the job does not comply with UK employment law, such as the National Minimum Wage or the Working Time Regulations
• you have given false or misleading information
• the job does not otherwise meet the definition of an eligible role, or the application does not otherwise meet the route's requirements

It may also reject the application, or grant fewer certificates than you asked for, if you miss a deadline for evidence, your justification or need is not credible, it is not satisfied the work will be guaranteed by the start date, you have a history of non-compliance, or the request is substantially the same as one already rejected. Persistently making applications that are rejected can itself lead to compliance action.

After a Defined CoS Is Granted

An approved Defined CoS appears in your SMS account and you can assign it. You must do so within 90 days. SMS guide 12 says Defined CoS "expire to the minute 90 days after being granted", so apply only when you genuinely expect to assign the certificate within that time. Once assigned, the worker has 3 months to use it.

The details from your application are fixed on the certificate and you cannot edit them when you assign it. You can add a sponsor note to change only these three things:

• Salary, provided the new figure is eligible for the same number of points as the original
• Weekly hours, provided you also update the salary and it still earns the same points
• Start and end dates, although the start date cannot be more than 3 months after the date the worker makes their application

If a revised salary or hours no longer earn the same points, the Home Office will cancel the CoS. Any other change, such as a different occupation code or a different job description, must be reported so that the Home Office can cancel the CoS. If your licence is downgraded to a B-rating or suspended, you cannot assign any unassigned Defined CoS. They are removed after 90 days unless you regain your A-rating and assign them first. If the Home Office finds a Defined CoS application was invalid before you have assigned the certificate, it reclaims the certificate from your account.

Only assign a Defined CoS for the job you described. The Home Office will revoke your licence if it finds you gave false information in the application. Its examples include paying a worker less than the salary in the application, which it can find through a compliance visit or by checking with HMRC; assigning the certificate for a different job; and using an inappropriate occupation code to meet the skill level.

Before You Assign a CoS

Part 2 of the sponsor guidance asks you to do four things before any certificate is assigned: check that the role is eligible for the route, make sure you will pay the worker appropriately, check that the worker is eligible, and meet any requirements specific to the route.

Your Rating and Licence Status

On the Scale-up and Seasonal Worker routes, you can only assign a CoS with an A-rating. On every other route you also need an A-rating, with two exceptions:

• a B-rated sponsor can assign a CoS to a worker applying for permission to stay on the same route as their last grant, where the sponsor assigned the CoS for that last grant and is continuing to sponsor them
• a UK Expansion Worker sponsor with a Provisional rating can assign a CoS to its Authorising Officer

Assigning a certificate to a worker you were not already sponsoring before you were downgraded is a ground on which the Home Office will revoke your licence.

You cannot assign any CoS while your licence is suspended, dormant or revoked. If your licence is suspended, a worker can still apply on a certificate you assigned before the suspension, but the Home Office will not decide the application until the reason for the suspension has been resolved, unless it falls for refusal on other grounds. A worker already granted entry clearance on your certificate can still travel and start work, provided the licence has not been revoked by the time they travel. If the licence is revoked, every certificate you have assigned becomes invalid and any entry clearance application relying on one is refused. The process is covered in Sponsor Licence: Suspension and Revocation.

Who Must Not Be Assigned a CoS

An SMS user must never assign a certificate to themselves, their partner or a close relative. The Home Office will revoke your licence if this happens. The sponsor guidance glossary defines partner or close relative as a person's spouse or civil partner; unmarried or same-sex partner; parent or step-parent; son, daughter, step-son or step-daughter; brother, sister, step-brother, step-sister, half-brother or half-sister; nephew, niece or cousin; aunt or uncle; and parents-in-law, brothers-in-law, sisters-in-law, sons-in-law and daughters-in-law. The only exception is on the UK Expansion Worker route with a Provisional rating, where the Authorising Officer, who must also be the Level 1 User, assigns their own CoS.

If an SMS user assigns a certificate to someone who is a partner or close relative of anyone else in your organisation, you must say so in a sponsor note where you know, or could reasonably be expected to know. Assigning a certificate to sponsor a worker in a personal capacity is a ground on which the Home Office will normally revoke. The rules on SMS users' conduct are in Sponsor Licence: SMS and Key Personnel.

Route-Specific Steps

Some routes need something done before a certificate can be assigned:

• Religious Worker: a resident labour consideration may be needed, and you must explain in a sponsor note how it was met
• Creative Worker: you may need to follow the code of practice for the sector
• International Sportsperson: you need an endorsement from the sports governing body. Assigning a CoS without a current endorsement is a ground on which the Home Office will revoke
• Service Supplier and Secondment Worker: you must register the contract the worker will service in your SMS account first
• UK Expansion Worker: with a Provisional rating, you must have your rating changed to an A-rating before sponsoring anyone other than the Authorising Officer

Switching From Another Route

Check that the worker's current route allows them to switch. If it does not, the Home Office will normally reject the application and the worker must leave the UK to apply for entry clearance. A worker who has, or last had, permission as a Student can only switch to a Worker, Global Business Mobility or Scale-up route if, on the date they apply, they have completed the course they were sponsored for, or are studying full time at degree level or above with a higher education provider with a track record of compliance and your CoS start date is no earlier than the course completion date, or are on a full-time PhD with such a provider and your CoS start date is at least 24 months after the PhD started. Check this before you assign the certificate. The detail is in Graduate and Student Switching.

A worker who applies to switch must not start working for you until the application is granted, unless their existing permission already allows them to do the work.

What Goes on the CoS

For a certificate to be valid, it must include:

• the route on which you are sponsoring the worker
• the worker's personal details, including name, nationality, date of birth, passport details and contact address
• the usual work address or addresses
• total weekly hours, or an average if they vary
• the job title, job description, start date, end date, salary (except for a Charity Worker) and occupation code
• whether you used an agent, such as a recruitment agency, employment business or other intermediary, to find the worker, and if so their details
• whether you certify maintenance
• for some routes, whether the worker needs an Academic Technology Approval Scheme (ATAS) certificate
• anything else the route-specific guidance requires

For a Skilled Worker, the certificate must also confirm the category (see below), that the worker is a new entrant with a brief explanation if they are claiming points under Option E or Option J, whether the job is on a client contract, that the occupation code is eligible, whether the job is on the Immigration Salary List or Temporary Shortage List, any professional registration the worker is legally required to hold, the PAYE reference, and extra information for some roles, including occupation code 6131, care workers and senior care workers, pre-registration nurses and midwives, jobs under the transitional provision for skill level, and Health and Care visa applicants.

Choosing the Skilled Worker Category

When you assign an Undefined CoS to a Skilled Worker, you choose a category from a drop-down list. The right one depends on the worker's current status and on whether you must pay the Immigration Skills Charge.

Salary and PAYE Details

When you assign a CoS you must give:

• the gross salary, being the total paid to the worker before tax, whether paid in the UK or from overseas. For a Skilled Worker, Senior or Specialist Worker, Graduate Trainee or UK Expansion Worker, the figure must not include allowances unless the Immigration Rules expressly permit it. For other routes, it includes allowances and guaranteed bonuses
• a separate total, and an itemised breakdown, of allowances and guaranteed bonuses, where the route permits them
• the PAYE scheme reference through which the worker will pay tax and National Insurance, if you are sponsoring a Skilled Worker, Senior or Specialist Worker, Graduate Trainee, UK Expansion Worker or Scale-up Worker. If you do not have to operate PAYE on the worker's earnings, you must explain why. A Scale-up Worker must be paid through PAYE

The salary must not be inflated to reflect tax relief or costs that apply to a settled worker but not to the sponsored worker. It can be expressed per hour, day, week, month or year, per contract, or per performance, though not every period is available on every route: Skilled Workers and Scale-up Workers cannot use a contract figure, Seasonal Workers cannot use a yearly figure, and a per-performance figure is only for International Sportspersons and Creative Workers. The figure must always be in pounds sterling. If the worker is paid from abroad in another currency, convert it at the OANDA rate on the day you assign the CoS, or for a Defined CoS on the day you applied, and update it with a sponsor note when you assign. If you will not pay the National Minimum Wage because a legal exemption applies, explain this on the certificate.

Which payments count towards a Skilled Worker's salary threshold is covered in Skilled Worker: Eligibility and Salary. Paying a worker less than the salary on their certificate, without telling the Home Office or where the reduction is not permitted, is a ground on which it will revoke your licence.

Choosing the Occupation Code

Every certificate must give the four-digit occupation code, also called the SOC code, that fits the job. For a CoS assigned on or after 4 April 2024, this is the SOC 2020 code from Appendix Skilled Occupations. SOC 2010 codes remain valid for certificates assigned on or before 3 April 2024. Which tables are eligible for which route, and the going rate for each code, are covered in Skilled Worker: Eligibility and Salary.

The Home Office is clear that the choice is yours. You are responsible for choosing the correct code, and the guidance says of the Home Office: "we cannot help you with this." The Office for National Statistics publishes detailed guidance on SOC 2020, and the University of Warwick's CASCOT tool can help you find the right code. Pick the code that matches what the worker will actually do, not the one that makes the job easier to sponsor.

A wrong code can delay an application or lead to its refusal. Giving false, misleading or incorrect information about the skill or salary level of a job, for example to help a worker score points, leads to compliance action that can include revocation. If the role a sponsored worker actually does does not match the occupation code or the job description on their certificate, the Home Office will revoke your licence.

The role and job description must be an accurate reflection of the work. If the job changes after the worker has been granted permission, and the change does not need a change of employment application, you must report it within 10 working days. How to report it is covered in Sponsor Licence: Compliance and Duties.

Start and End Dates

Start date. Enter the date you expect the worker to start if their application is granted. For an extension, the Home Office recommends the day after the worker's current permission ends.

Two limits then apply at once. The worker must apply no more than 3 months after the certificate was assigned, and cannot apply more than 3 months before the start date on it. If you assign a CoS too early, the worker can be caught between the two: for example, a certificate assigned in January with a start date in August expires in April, before the worker is allowed to apply. The Home Office expects you to time your recruitment and assignment so that this does not happen.

If the start or end date changes before the worker applies, or before their application is decided, add a sponsor note, because it can affect how much permission is granted. A worker can start as soon as they have permission, even before the start date on the certificate, and you do not need to report an earlier start. A worker who has not started within 28 days of the relevant date must be reported. That rule, and what counts as the relevant date, is covered in Sponsor Licence: Compliance and Duties.

End date. Enter the end of the period you intend to sponsor the worker, up to the maximum allowed on the route. Some examples:

• Skilled Worker: up to 5 years
• Skilled Worker new entrant: up to 4 years, less any time already spent in the UK as a new entrant on the Skilled Worker or Tier 2 (General) routes, or on the Graduate route
• Pre-registration nurse or midwife: no more than 8 months, and you must confirm you will stop sponsoring them as a nurse or midwife if they do not achieve full NMC registration within 8 months of the start date
• Prison service officer (3314) under the additional transitional provisions: no more than 3 years after the start date
• International Sportsperson: no later than the period in the sports governing body's endorsement
• Charity Worker: no more than 12 months in total on the route

If you assign a certificate for longer than the route allows, the Home Office will limit the permission it grants, or refuse the application if the worker has already used up the maximum. On the Government Authorised Exchange and Seasonal Worker routes it will report you to the endorsing government department, and if that department withdraws its endorsement, your licence will be revoked.

A Scale-up Worker's certificate has no end date. Instead, you confirm in the CoS declaration that you expect the worker to work for you for at least the first 6 months of their permission.

Other Choices on the Certificate

• Certifying maintenance. On most routes an A-rated sponsor can tick a box to confirm the worker, and any dependants, meet the financial requirement, so they do not have to prove their funds. If you do not want to certify maintenance for dependants, add a sponsor note after assigning. You cannot certify maintenance on the UK Expansion Worker route.
• ATAS. ATAS applies where you are also licensed as a Student sponsor, on the routes listed in Part 2. On those routes you must answer yes or no to whether the worker needs an ATAS certificate every time you assign a CoS, including for an extension. In some cases, where you answer no, you must also briefly explain why, in the job description or a sponsor note. Stating that a worker does not need one when they do is a ground on which the Home Office will normally revoke under Annex C2(z); Part 2, paragraph S7.39, says it "will consider revoking". Failing to give the confirmation at all is a ground on which it may revoke, and so is sponsoring a worker who needs an ATAS certificate but does not have one.
• Multiple entry. If the worker will travel in and out of the UK regularly for the job, you can tick the multiple entry box. It is optional and neither adds nor removes anything; it simply shows the Home Office their likely travel.
• Group CoS. On the Creative Worker route, one certificate can cover a group, such as a band or dance troupe, or a performer and their entourage.

After You Assign a CoS

Giving the Worker the Reference Number

Assigning a certificate generates a reference number. You must give it to the worker, and they must enter it in their application. The Home Office asks you to treat it as secure and confidential information. The worker does not need a copy of the certificate to apply, but you can give them one if they ask, using the "View CoS" and "Print" functions in the SMS.

How Long a CoS Lasts

The worker must use the certificate in a valid application within 3 months of it being assigned. If they do not, it expires, and if you still want to sponsor them you must assign and pay for a new one. On the Skilled Worker route, the Home Office may reject an application without considering it where the certificate was assigned more than 3 months before, and will refuse one made more than 3 months before the start date on the certificate. Any Immigration Skills Charge due must also be paid; until it is, the certificate is invalid.

The SMS shows each certificate's status:

A used certificate cannot support another application. The one exception is the Creative Worker visa concession, where the same CoS can be used each time the worker re-enters the UK, provided it is still valid and they continue to qualify.

If the application is refused, and any administrative review is dismissed, you must assign and pay for a new certificate if you still want to sponsor the worker. If the application is rejected as invalid, or the worker withdraws it, the certificate stays as Assigned and they can reuse it, provided it has not expired.

Correcting or Updating a CoS

While a certificate shows as Assigned, you can add a sponsor note to change the start or end date, update the salary or working hours, correct a minor error, or add information. For example, you can use a sponsor note to explain how a Skilled Worker qualifies for the Health and Care visa, and for a Religious Worker you must use one to explain how the resident labour consideration was met.

A single minor mistake, such as a mistyped name or date of birth, can be fixed with a sponsor note. You must withdraw the certificate and assign a new one if you have made a significant error, such as:

• entering the wrong occupation code
• assigning the certificate on the wrong route or in the wrong sub-category
• getting more than one of the worker's nationality, date of birth and surname wrong

More than one error in the worker's personal details will normally mean assigning a new CoS. Once a certificate has been used, changes are reported through the "Report migrant activity" function instead, which is covered in Sponsor Licence: Compliance and Duties.

Withdrawing a CoS

You can withdraw a certificate through the SMS at any time before it is used in an application. The CoS fee is not refunded when a certificate is withdrawn or cancelled. Any Immigration Skills Charge you paid is refunded in full if you withdraw the certificate before it is used. The ISC refund rules are explained in Visa Fees and Sponsorship Costs.

A worker can normally have only one certificate assigned for use in an application at a time. The only exception is consecutive engagements with more than one sponsor on the Creative Worker route. So if a worker you assigned a CoS to decides to accept another sponsor's offer, the new sponsor cannot assign theirs until you withdraw yours. The worker must ask you in writing or by email and give you 5 working days. If you do not act, they send a reminder and you have a further 5 working days. If you still do not withdraw it, the worker can ask the Home Office to cancel it, which it will not do until it has talked to you about why you have not withdrawn it. Failing to withdraw a certificate within these time limits can lead to compliance action.

When the Home Office Cancels a CoS

The Home Office can cancel a certificate that should not have been assigned: for example, one assigned through misrepresentation or fraud, or where the correct CoS fee was not paid in full. Any application relying on a cancelled or withdrawn certificate is refused.

If the worker has already been granted permission on a certificate that was improperly assigned, the Home Office will cancel or shorten that permission:

• if the worker was not actively involved, permission is normally shortened to 60 days, so they can find a new sponsor, apply on another route or arrange to leave. It is not shortened if 60 days or less already remain
• if the worker was actively involved, permission is cancelled completely and they must leave the UK immediately

What a worker can do after losing sponsorship is covered in Skilled Worker: Job Loss and Second Jobs.

Once the Worker Has Permission

A worker can start as soon as they are granted permission. From that point your reporting duties apply to them: a late start, unauthorised absence, changes to the job or salary, and the end of their employment all have deadlines, set out in Sponsor Licence: Compliance and Duties. On the Scale-up route, you must also report the date the worker actually starts, within 10 working days of it.

When a Worker Needs a New CoS

A certificate supports one application. A worker you already sponsor needs a new one in these situations:

• Extending: when the worker's permission is about to expire and you want them to continue in the same role, or in a different job in the same occupation code, assign a new CoS and the worker makes an extension application. Set the start date as the day after their current permission ends. The worker cannot apply more than 3 months before that date. A move to a different job in the same occupation code during the permission, where you assigned the CoS for the last grant, does not need a new certificate at that point, provided the new role meets the route's requirements, but you must report it within 10 working days.
• Changing employment: a new job in a different occupation code, a move from a job on the Immigration Salary List to one that is not, or a move to a different sponsor or employer. The worker needs a new CoS and must make a change of employment application, and the new job cannot start until it is granted. There are exceptions, including some TUPE transfers and moves between branches of the same organisation. Failing to assign a new CoS where a change of employment application is needed is a ground on which the Home Office will revoke. The application itself is covered in Skilled Worker: Apply, Switch and Extend.
• Taking a second sponsored job: a worker on a Worker route, other than Senior or Specialist Worker, may be allowed to take secondary employment with a second licensed sponsor. The second sponsor assigns its own CoS once the worker has used their first one and started that job, and the worker then applies for permission to stay covering both jobs. See Skilled Worker: Job Loss and Second Jobs.
• Permission lapsing abroad: if a worker's permission lapses or expires while they are outside the Common Travel Area, they need a new application and, in most cases, a new CoS to return.
• After a refusal: a refused application uses up the certificate.

What a CoS Costs

You pay a fee each time you assign a certificate.

If you do not pay the correct fee, the Home Office may cancel the certificate, and any application relying on it may be rejected or refused. There is no extra charge to apply for a Defined CoS.

On most sponsored routes the fee is yours to pay, and you must not pass it on. You must not recoup, or try to recoup, any part of the CoS fee or associated administrative costs from the worker:

• on the Skilled Worker route, where the CoS was assigned on or after 31 December 2024
• on any Global Business Mobility route, and on the Minister of Religion, International Sportsperson, Scale-up and Seasonal Worker routes, where the CoS was assigned on or after 9 April 2025

Doing so is a ground on which the Home Office will normally revoke your licence. Associated administrative costs are defined widely. They include priority service fees for requesting or assigning a certificate, and legal fees for advice on assigning, requesting or applying for one.

On the Skilled Worker and Senior or Specialist Worker routes you may also pay the Immigration Skills Charge each time you assign a certificate. The full cost of sponsoring a worker, including the ISC, visa fees and the Immigration Health Surcharge, is set out in Visa Fees and Sponsorship Costs and in our post on the cost of sponsoring a worker in the UK. Our visa fee and IHS calculator works out the figures for a particular worker.

How to Check a CoS Is Genuine

This section is written for workers who have been offered a job and a certificate, and want to know whether they can trust it.

Much of the advice online tells you to inspect the certificate itself: how many characters the reference number has, which letter it starts with, how long before it expires. None of that comes from the Home Office, which publishes no format for CoS numbers or licence numbers, and a fraudster can copy any format in seconds. A check like that can leave you feeling safe about a fake. The checks below are based on the rules themselves, which a fraudster cannot change.

The Two Checks That Settle It

1. You should never be asked to pay for a Skilled Worker CoS. The sponsor pays the certificate fee. On the Skilled Worker route it is against the rules for a sponsor to ask you to pay any part of it, or any of the costs linked to it, and the Home Office treats doing so as a ground on which it will normally revoke the sponsor's licence. The same ban covers certificates on the Global Business Mobility, Minister of Religion, International Sportsperson, Scale-up and Seasonal Worker routes, and sponsors on every route are barred from passing on the Immigration Skills Charge or the sponsor licence fee. It does not matter what the payment is called: a fee, a deposit, a processing charge, a sponsorship cost or a refundable guarantee. If you are asked to pay for a Skilled Worker certificate, either the offer is a scam or the sponsor is breaking the rules. Do not pay.

2. An overseas care job cannot come with a CoS. A Defined CoS cannot be issued for occupation codes 6135 (care workers and home carers) or 6136 (senior care workers), and a Defined CoS is what a Skilled Worker applying from outside the UK needs. If you are outside the UK and someone offers you a care worker or senior care worker job with a certificate, that certificate cannot lead to a visa. Offers like this are a common scam, and the answer is always the same.

Two More Checks That Work

3. Find the sponsor on the register. The Home Office publishes a register of licensed sponsors for the Worker and Temporary Worker routes. For each organisation it lists the name, town, type of licence and rating, and route. Check three things:

• the organisation is on the register at all
• the route on your certificate is listed for that organisation. A sponsor licensed only for one route cannot sponsor you on another
• the rating. A B-rated sponsor cannot assign a certificate to a new worker; it can only extend the permission of a worker it already sponsors on the same route

The register lists the organisation's legal name, which can differ from the name it trades under, so check the company's registered name as well. The register does not show licence numbers. Our free sponsor licence status check searches the register for you, and our guide on how to verify any employer's licence explains what the entries mean.

4. Confirm the offer with the employer yourself. A real sponsor can see every certificate it has assigned in its SMS account and can confirm yours. Contact the employer using details you have found yourself, for example on its own website or through Companies House, not the phone number or email address in the message that brought you the offer. Anyone can put a real company's name on a fake offer.

Other Things to Look At

• Your details and the job. Your name, nationality, date of birth and passport details should be correct, and the job title, hours, salary and work address should match the offer you accepted. Whether the job and salary are eligible for the route is explained in Skilled Worker: Eligibility and Salary.
• The PAYE reference. On a Skilled Worker, Senior or Specialist Worker, Graduate Trainee, UK Expansion Worker or Scale-up Worker certificate, the sponsor must give the PAYE reference it will use to pay you, or explain why PAYE does not apply.
• Only one CoS at a time. If another employer has already assigned you a certificate that you have not used, a new sponsor cannot assign one until the first is withdrawn.
• You only need the number. You apply with the reference number. You do not need the certificate itself, although a genuine sponsor can print a copy from the SMS, so receiving one is not suspicious on its own.

Why it matters to you, not only the employer. If the Home Office cancels a certificate because it should not have been assigned, any application relying on it is refused. If you have already been granted permission on one, it can be shortened to 60 days, and if you were actively involved in the certificate being improperly assigned, it will be cancelled outright and you will have to leave the UK immediately. Paying for a certificate can put you on the wrong side of that line. If you are unsure, take advice from a regulated immigration adviser before you pay anything or send any documents. Our Skilled Worker visa service page explains how we help workers applying on the route.

For Employers: Protecting Your Licence

Fraudsters use the names of real licensed sponsors, so your organisation can be drawn into a scam it knows nothing about. Treat every CoS reference number as confidential, as the Home Office asks. Keep SMS access to the people who need it and never share log-ins, which is a breach in its own right and is covered in Sponsor Licence: SMS and Key Personnel. If a worker contacts you about a certificate you did not assign, check your SMS account, and do not confirm anything that is not in it.

Revocation Grounds Linked to a CoS

Part 3 of the sponsor guidance grades each ground for revocation. Annex C1 lists grounds on which the Home Office will revoke, Annex C2 grounds on which it will normally revoke, and Annex C3 grounds on which it may revoke. The main grounds that turn on a certificate are:

Part 2, paragraph S2.11, grades two failures together at "will normally revoke": assigning a Defined CoS for a job other than the one described in the application for it, and assigning an Undefined CoS where a Defined one is required. Sponsor a Skilled Worker grades the first as "will revoke" (SK12.35) and the second as "likely to revoke" (SK12.2). Both gradings are set out here as each document states them. The process that follows a decision to act against a licence is covered in Sponsor Licence: Suspension and Revocation, and the full list is in Part 3 of the sponsor guidance.

The rules on assigning a certificate are set out in full in Part 2 of the sponsor guidance and, for the Skilled Worker route, in Sponsor a Skilled Worker. The screens are explained in SMS guide 8 on creating and assigning a CoS.

Detailed Guides on This Topic

• What is the UK Certificate of Sponsorship? A short guide An introduction to certificates for workers and employers.
• Annual CoS allocations: what to do when yours is due to expire How the CoS year works and what to do before it ends.
• UK Sponsor Management System guide for employers The SMS screens, including creating and assigning certificates.
• How to verify any employer's sponsor licence Reading the register of licensed sponsors.

How Can WorkPermitCloud Help?

WorkPermitCloud is a Legal and HR-tech company specialising in UK business immigration. We help sponsors manage their certificates from start to finish: estimating and requesting allocations, preparing Defined CoS applications, choosing the right category and occupation code, assigning certificates correctly, and correcting or withdrawing them when plans change. For workers, we can check an offer and a certificate before you rely on them. See our sponsorship duties service for how we support sponsors day to day, and our sponsor licence service if you do not yet hold a licence.

WorkPermitCloud never sells a Certificate of Sponsorship and never asks a worker to pay for one. No legitimate Skilled Worker sponsor does, because passing that cost to a worker is a ground on which the Home Office will normally revoke a sponsor licence. If anyone offers you a CoS in our name, or asks you to pay for one, it is not us. Before you send money or documents to anyone claiming to be from WorkPermitCloud, find our contact details yourself at workpermitcloud.co.uk and check with us directly, rather than using the details in the message you received. Our fraud alert on recognising genuine communication from WorkPermitCloud explains more.

Conclusion

A Certificate of Sponsorship is a short online form, but almost every part of it is a statement the Home Office can check and act on: the type, the occupation code, the salary, the dates and the person who assigns it. Most of the problems sponsors run into come from treating it as paperwork. They assign an Undefined CoS where a Defined one was needed, choose a code for convenience, assign too early for the worker to apply, or let an allocation run out just before an extension is due. Sponsors who understand the two types, the two clocks and their allocation year avoid most of them. For workers, the protection is simpler still: a Skilled Worker sponsor cannot charge you for your certificate, and no Defined CoS can exist for an overseas care worker job.

Glossary