Assigning Certificates of Sponsorship (CoS)

What is assigning a CoS?

Assigning a Certificate of Sponsorship creates an electronic record the worker uses to apply for their visa. Each assignment must accurately describe salary, SOC code, dates, and whether the CoS is defined or undefined.

Defined vs Undefined CoS

Defined CoS is usually required for workers applying from outside the UK. Undefined CoS is typically used for in-country switchers or extensions. Using the wrong type can invalidate the worker's visa application.

Skilled Worker alignment

The role must meet minimum skill (RQF 3+) and salary thresholds when the CoS is assigned unless a listed exception applies — thresholds may change as of 2026.

Job description and SOC code

Accurate job titles and SOC codes matching genuine duties are essential — Home Office checks consistency with the worker's visa application.

Salary and Immigration Skills Charge

Pay must meet rules; employers may need to pay Immigration Skills Charge when assigning CoS to new skilled workers from abroad.

Worker immigration history

Passport details and prior leave help choose defined vs undefined CoS and flag switch restrictions.

How to apply

Request defined CoS approval via SMS where required, or assign undefined CoS directly when permitted. Workers apply for visas only after CoS assignment is confirmed.

Costs & processing time

CoS assignment itself has no separate Home Office fee, but Immigration Skills Charge and visa fees apply to the worker. Charge rates are set by government and subject to change as of 2026.

Common reasons applications are refused

• Wrong CoS type for worker's location or immigration status

• Salary or SOC code below skilled worker minimums

• CoS details not matching genuine role

• Assigning while licence suspended or B-rated without permission

• Missing Immigration Skills Charge payment when due

Related guidance: Apply for Sponsor Licence, Sponsor Licence Renewal, Suspension & Revocation, and Settlement & ILR.