Guide for sponsors
Certificate of sponsorship: what it is and how to assign one
Last reviewed: 16 October 2026
Written for care providers who hold a sponsor licence. This isn't official guidance, so check the Home Office sponsor guidance on gov.uk before you act.
What is a certificate of sponsorship?
A certificate of sponsorship (CoS) is an electronic record that a licensed sponsor creates for a worker it wants to employ. It has a unique reference number, and the worker quotes that number when they apply for their visa.
It isn't a physical certificate or a letter. It confirms the job, the salary, the occupation code and the start date, and the sponsor's statement that the role is real and meets the route's rules. The Home Office uses it to decide the visa application alongside the worker's own evidence.
The Home Office gives sponsors an allocation of certificates. The sponsor then assigns them to individual workers through the sponsor management system (SMS). Only a business with a valid sponsor licence can do this, which is why keeping on top of sponsor licence compliance matters before you think about assigning anything.
Defined and undefined certificates, and which you need
A defined CoS is for a Skilled Worker applicant applying from outside the UK. You apply to the Home Office for each one, role by role.
An undefined CoS is for Skilled Workers applying from inside the UK, and for applicants on all other visas. These come from an annual allocation that you request for your licence.
For care providers. Since 22 July 2025, care workers and senior care workers (occupation codes 6135 and 6136) can't be sponsored from outside the UK. Workers already in the UK can switch in until 22 July 2028. Anyone switching from a different visa route must have worked for the sponsoring provider for at least three months first. For these roles, the undefined certificate is the one you'll use when hiring sponsored care workers.
Defined certificates still apply to other health roles hired from overseas, such as nurses.
What a certificate of sponsorship costs
The employer pays the certificate fee and the immigration skills charge. Current figures are on the gov.uk page on sponsoring a worker.
| The fee | What it covers | Who pays it |
|---|---|---|
| Certificate of sponsorship fee £525 per certificate | Assigning one certificate to one worker. | The employer. It can't be passed on to the worker. |
| Immigration skills charge Small or charitable sponsors: £480 for the first 12 months, then £240 for each additional 6 months. Medium or large sponsors: £1,320 for the first 12 months, then £660 for each additional 6 months. | A charge for the length of sponsorship, paid in full when the certificate is assigned. | The employer. It can't be passed on to the worker. |
| Visa application fee (Health and Care Worker visa) £324 for a certificate of up to three years, £628 for longer | The worker's own visa application, which they make using the certificate number. | The worker. |
| Immigration health surcharge Health and Care Worker visa applicants are exempt | Access to the NHS for the length of the visa. | Not applicable. |
You're usually a small sponsor if at least two of these apply: annual turnover of £15 million or less, total assets of £7.5 million or less, 50 employees or fewer. Asking a worker to pay the certificate fee or the skills charge can lead to your licence being revoked. See the gov.uk page on the immigration skills charge.
How to assign a certificate of sponsorship
You assign a certificate in the sponsor management system. The steps below follow the usual order and describe what you do at each stage.
- Sign in to the sponsor management system as your authorising officer or a level 1 user, since only those roles can assign certificates.
- Confirm you have an unused certificate available, either a granted defined CoS for this overseas role or space in your undefined allocation for an in-country worker.
- Start a new certificate and choose the correct route for the worker, which for most care providers is Skilled Worker.
- Enter the worker's personal details exactly as they appear in their passport.
- Enter the job details, including the occupation code, job title, weekly hours, gross salary and the address where the worker will be based.
- Write a job description that matches the duties the worker will carry out, so the role on the certificate lines up with the occupation code you chose.
- Add the start date and, where the role needs it, any sponsor note explaining points the caseworker should know about.
- Check every field against the contract and passport, then pay the certificate fee and the immigration skills charge to assign it.
- Give the worker the certificate number so they can make their visa application, and keep a copy of the record on their file.
How long it takes, and how long it lasts
Processing time. Assigning a certificate you already hold is usually immediate once you submit it in the SMS. Defined certificate requests are usually approved within one working day, although it can take longer if UKVI needs to do further checks. Requests for extra undefined certificates usually get a decision within 12 weeks. A paid priority service gives a decision within 5 working days.
Validity period. A granted defined certificate must be assigned to a worker within 3 months, or it's removed from your account. Once assigned, the worker must use the certificate to apply for their visa within 3 months, and can't apply more than 3 months before the job's start date.
Undefined allocation. Undefined certificates are allocated each year. When you apply for the licence, you estimate how many you'll need in the first year.
Checking, cancelling and correcting a certificate
Finding a certificate number. Sign in to the SMS and search your assigned certificates by the worker's name or by reference. The number is shown on each record, and the worker will also need it for their application.
Cancelling a certificate. A certificate can only be withdrawn before the worker submits their visa application. The £525 certificate fee isn't refunded when a certificate is withdrawn.
Correcting details. A sponsor note can fix a single minor error, such as a mistyped name or date of birth. Bigger errors, such as the wrong occupation code or route, mean withdrawing the certificate and assigning a new one. Most changes to a sponsored worker's circumstances must be reported in the SMS within 10 working days. The rules are in the Home Office guidance for sponsors on gov.uk.
What goes wrong, and what it costs you
The common mistakes are a salary below the required threshold, the wrong occupation code, a job description that doesn't match the work done and hours that differ from the contract. Any of these can lead to the visa being refused. If the application is refused or withdrawn, the immigration skills charge is refunded in full, usually within 90 days. The certificate fee isn't refunded.
The Home Office treats an incorrectly assigned certificate as a compliance failure. It can downgrade your licence to a B-rating with an action plan, suspend it or revoke it. B-rated sponsors can't assign new certificates, and a revocation affects every sponsored worker you employ.
Lifted monitors certificate assignments and reporting duties for care providers as part of our sponsorship compliance service. If you'd like us to look at yours, you can book a call with our team.