About this app
SeaClaim tells you exactly where you stand on your Seafarers' Earnings Deduction claim - and explains why. Other trackers give you a number. SeaClaim shows which rule was breached, how close you are to losing eligibility, and what you need to do to stay on track. No ambiguity, no guesswork. THE PROBLEM UK seafarers claiming SED deal with complex HMRC rules: the half-day rule, 183-day UK stay limits, and qualifying periods that must span 365+ consecutive days. Most people track this manually with spreadsheets or paper worksheets - and don't find out they've lost eligibility until it's too late. HOW IT WORKS Log your voyages - departure and return dates - and SeaClaim does the rest. The calculation engine applies the full HMRC HS205 methodology, tested against hundreds of real-world scenarios. FEATURES - Dashboard - Your qualifying status, colour-coded voyage history, and eligibility progress in one view. - Clear Explanations - See exactly why a period qualified or failed: half-day breach, 183-day rule, insufficient days. Not just a yes or no. - Risk Metrics - Days-in-hand before a rule break, fail date, and 183-day UK streak tracking. Plan shore leave without risking your claim. - Smart Notifications - Alerts when approaching the half-day threshold or 183 consecutive UK days. - HS205 Working Sheet Export - Generate a completed HMRC working sheet PDF (columns A-H) ready to attach to your Self Assessment or send to your accountant. - CSV Export - Download voyage records and eligible periods as spreadsheet files for accountants or personal records. - Self Assessment Guide - Step-by-step walkthrough of the HMRC forms for claiming the Seafarers' Earnings Deduction on your tax return. Which boxes to fill in, what to enter. - Includes a tax deduction calculator so you can see how much income is tax deductible. - Document Storage - Upload payslips, contracts, discharge book pages, travel vouchers and other SED evidence. Organised by tax year. Export everything as a zip. FREE & PRO Start for free. Upgrade to Pro for unlimited entries, risk metrics, notifications, document management and export features. BUILT FOR SEAFARERS Whether you work on merchant vessels, offshore support vessels, ferries, cruise ships or commercial shipping - if you claim SED, SeaClaim is for you. WHY SeaClaim? - Clear eligibility explanations, not just pass/fail - Algorithm tested against hundreds of scenarios (including multi-year, multi-eligible-period scenarios where others have failed or are ambiguous) - Automatic half-day and 183-day rule monitoring - HS205 working sheet PDF export - Risk metrics and alerts to prevent rule breaks - Self Assessment guide walks you through the HMRC forms step by step - Store your SED evidence organised by tax year with an HMRC checklist - Replaces manual spreadsheets and paper worksheets SeaClaim is an independent app, not affiliated with HMRC or any UK government entity. The eligibility rules it implements are based on official HMRC guidance on the Seafarers' Earnings Deduction: https://www.gov.uk/guidance/seafarers-earnings-deduction-tax-relief-if-you-work-on-a-ship. This app does not provide tax advice. Verify figures before submitting to HMRC. Terms of Use: https://sites.google.com/view/seafarer-tax-assistant/terms Privacy Policy: https://sites.google.com/view/seafarer-tax-assistant/privacy-policy
Latest release
What’s New
Store evidence document features
Audience growth
Ratings growth
Baseline captured. Growth appears after the crawler observes a changed rating count.
Momentum comes from crawler snapshots for the tracked storefront. “Viral growth signal” means unusually fast recent rating gains; it is an indicator, not download data.
Price tracking
Price intelligence
First snapshot captured. The trend line starts after the next crawler price observation.
- First observed Aug 26, 2026 · 5:44 PM Free