For UK Sponsors

Check the going rate before you assign the CoS.

Track defined and undefined CoS allocation, run a going-rate salary check against the latest SOC code, and stay on top of every reporting trigger — 10 working days for worker-level events, 20 for business-level changes.

Two Kinds of Certificate

Defined vs Undefined CoS.

The distinction matters for the application route and your annual allocation.

Defined CoS

Used when sponsoring a Skilled Worker who is applying from outside the UK. Requested through SMS and confirmed before assignment.

Best practice: validate the salary against the going rate before the request.

Undefined CoS

Used for in-UK Skilled Worker applications and most other Worker / Temporary Worker routes. Drawn from your annual allocation.

The platform shows your remaining allocation in real time.

Salary Check Built In

Powered by our Skilled Worker Salary Calculator.

The same calculator that handles 412 SOC 2020 occupation codes powers the per-CoS salary check inside the platform. Look up the going rate, pro-rate for working hours, and compare against the general threshold — in one place, no double entry.

Try the public calculator

What the salary check covers

  • SOC 2020 going rate lookup (412 codes)
  • General Skilled Worker threshold check
  • NHS and education pay-scale variants
  • Hours-per-week pro-rating
  • Transitional arrangements (where they apply)
Reporting Triggers

Each reportable change becomes a task.

The Sponsor Guidance asks you to report most worker-level events within 10 working days. The platform turns each one into an assigned action with a due date.

Start date confirmed

Or a no-show — reportable within 10 working days.

Salary or role change

Including promotions, pay rises and pay cuts.

Work location change

Including extended remote-working arrangements.

Early termination

Resignation, dismissal or unauthorised absence.

Frequently asked questions

Defined CoS is used when sponsoring a Skilled Worker who is applying from outside the UK — each one is requested through SMS and confirmed by UKVI before assignment. Undefined CoS is used for in-UK Skilled Worker applications and most other Worker and Temporary Worker routes; it draws from your annual allocation.

Look up the SOC 2020 code, find the going rate, pro-rate for the worker's contracted hours, then compare against the going rate and the general threshold — whichever is higher. I-Migrator runs that calculation as part of the CoS workflow using the same calculator that powers our public Skilled Worker Salary Calculator.

Most worker-level events: start dates, no-shows, terminations, unauthorised absences of more than 10 working days, salary or role changes, and changes to work location (gov.uk Sponsor Guidance, Part 3). Significant changes to your business itself are reported within 20 working days.

Yes, withdrawal is possible but in most cases the assignment still counts against your allocation. Best practice is to validate the salary, SOC code and route eligibility before the CoS is assigned in SMS.

No. CoS assignment happens in the Home Office Sponsor Management System (SMS). I-Migrator prepares the data, runs the salary check, and surfaces every reporting trigger after assignment so nothing falls off the calendar.
Part of the Compliance Platform

Connect with the rest of the workspace

See the CoS workflow end-to-end

A short walkthrough of allocation tracking, salary validation, and the post-assignment reporting calendar.

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Sources: gov.uk — Certificates of sponsorship · Your responsibilities as a sponsor.