Seafarers’ Earnings Deduction is claimed on a Self Assessment tax return. It is never applied automatically, your employer cannot claim it for you, and HMRC will not give it to you because you happen to work at sea. If you do not file, you do not get it.
Claiming, step by step
- Register for Self Assessment if you are not already in it. You will be given a Unique Taxpayer Reference, and this takes time — do not leave it to January.
- Build your day count. List every date you left and entered the UK. This establishes whether you have an eligible period, and which earnings fall inside it.
- Identify the qualifying earnings. Only earnings from employment as a seafarer, on a ship, within the eligible period.
- Complete the employment pages with your pay and any tax deducted, as on your P60 or payslips.
- Enter the deduction in the Seafarers’ Earnings Deduction box on the Additional Information pages (SA101).
- List the ships you worked on during the year in the additional information box on the main return.
- File by 31 January following the end of the tax year for an online return.
Box numbers move between tax years. HMRC renumbers the return from time to time. Check the current year’s HS205 helpsheet for the exact boxes rather than relying on last year’s return.
The evidence to keep
HMRC’s instruction is to keep your discharge book and all other documents supporting the claim, not to send them, and to expect that you may be asked for them later. In practice that means:
| Proves | Documents |
|---|---|
| You worked on a ship | Discharge book, contracts of employment, sign-on and sign-off letters |
| Where you were, day by day | Flight bookings, boarding passes, passport stamps, a travel log |
| Where the ship went | Itineraries, port lists, voyage records showing foreign ports |
| What you earned | Payslips, P60, bank statements |
Keep them for the full period HMRC can open an enquiry. A claim that is right but cannot be evidenced is treated the same as one that is wrong.
If you live in an EEA state
Non-UK residents who are resident for tax purposes in an EEA state, and have had UK tax deducted under PAYE, can reclaim it using form R43M(SED) rather than a Self Assessment return.
Where claims go wrong
- Counting by tax year. The eligible period does not follow the tax year. Earnings are matched to the period, not the other way round.
- Counting the day of travel wrongly. The test is where you were at midnight.
- Claiming for an installation. Rigs, FPSOs, drillships and flotels are not ships.
- Missing the ships from the return. HMRC asks for vessel names. Leaving them off invites a question.
- No records. Reconstructing four years of travel from memory after HMRC asks is a bad position to be in.
Common questions
Can my employer apply SED through payroll?
No. SED is claimed by the individual on a tax return. If PAYE tax has been deducted, the claim produces a repayment.
I have never filed a return. Have I missed out?
Not necessarily. Earlier years can often still be claimed. See backdating a claim.
How long does a repayment take?
It varies with HMRC’s workload and whether the return is selected for a check. A complete, well-evidenced return is the thing within your control.
Do I have to use an accountant?
No. You can file your own return. Most seafarers use a specialist because the day count is unforgiving and an error in it undoes the whole claim.
Not sure where you stand?
Tell us your vessel, your dates and where you sailed. We will tell you plainly whether you have a claim.
Related: Do I qualify? · Tax return checklist · Backdating a claim
Based on HMRC Helpsheet HS205, Seafarers’ Earnings Deduction. Tax rules change and individual circumstances differ — this page is general information, not advice on your own position.
