Don't miss out on100% tax relief
Track your time abroad. Claim what you're owed.
Try our free eligibility checker to see if you qualify (1 min / 6 steps)
How it works
Stay on top of your seafarers tax in 3 simple steps
1. Log your time abroad
Enter departure/return dates into your own personal calendar. We'll keep track of all your time abroad in one place, accessible from anywhere online.
2. Track your eligibility
Get live status updates. Our app automatically checks the 365‑day rule & half‑day rule so you don't have to.
3. Save your claim
Sign up for free to secure your data and generate HMRC forms (HS205 working sheet). Know where you stand, and share with your accountant.
Why choose Seadays
The easiest way to track your days abroad and build your claim.
Up to date
Designed in line with latest HMRC guidance.
Saves time
No spreadsheets, no paperwork – just simple tracking.
Free to start
Accountant‑ready reports with no upfront costs.
23.7K
UK seafarers active at sea in 2024
≈15K
Seafarers benefiting from SED (1999 estimate)
100%
Relief on qualifying seafaring earnings
What you get
Everything you need to build and defend your claim
Seadays gives you a private, seafarer-first workspace that keeps your voyages compliant, your records organised, and your tax relief on track.
Private dashboard
View every trip, claim milestone, and supporting document from a secure workspace that is yours alone.
Calendar at a glance
Plot departures and returns on an interactive calendar so you always know how many days you have outside the UK.
Abroad trip tracking
Log your trips abroad and upload evidence documents in seconds to keep things updated without the hassle of spreadsheets.
SED status updates
Monitor the 365-day and half-day rules automatically with colour-coded progress and alerts when you qualify.
Smart reminders
Get notified on a regular basis so you never lose track of your claim.
Be HMRC ready
Produce HMRC HS205 working sheets and store your evidence for each trip. Ready to share with your accountant and HMRC if needed.
Inside or outside the 12NM limit?
Unsure if your current position counts as a day abroad? Use our interactive 12NM limit checker to verify your coordinates against UK territorial waters instantly.
Generate your HS205 form instantly
Don't struggle with manual calculations. Enter your dates and let our free tool generate a compliant HMRC HS205 working sheet for you to download and keep.
Need step-by-step SED guidance?
Explore our in-depth HS205 explainer with examples, day-counting tips, and compliance checklists tailored for seafarers. It’s updated with the latest HMRC rules.