← All tools

UK SED calculator

Estimate UK Seafarers Earnings Deduction eligibility windows.

365-day period ends

27 Jul 2027

Days elapsed

31 / 365

UK days used

20 / 183

You're within the usual 183-day UK allowance, with 163 UK days still available in this 365-day period.

This is a simplified estimate of the standard Seafarers' Earnings Deduction rule (365-day eligible period, up to 183 days in the UK) — it is not tax advice. Eligibility also depends on your ship, voyages, and residency status. Confirm your claim with HMRC's official Seafarers' Earnings Deduction guidance (search “HS205” on gov.uk) or a qualified accountant.

Track all your offshore certifications

Upload certificates, set expiry reminders, and never miss a renewal — completely free on CrewVal.

Create free account

Free to join. No credit card required.