Your base airport decides more than your flight plan does

Figures relate to tax year 2025-26 (UK) · 2025 (US)

One fact settles most of an aircrew tax return. Not the destinations, not the hours, not the nights away.

It is the airport you report for duty at. Your employment sits where your base sits, whatever the roster does afterwards.

So airline crew who fly four continents a month are usually taxed by one country, and it is the dullest one on the list.

Key takeaways

• There is no aviation version of the seafarers deduction.
• Your base airport usually drives where you are taxed.
• Airline crew are still judged on the ordinary residence tests.
• Time in the air counts as foreign for neither American test.
• The treaty has an article for aircraft crew, but citizenship undercuts it.
• National Insurance generally follows your base, not the flag.
• Layovers abroad do not build the 330 days airline crew need.
• The foreign tax credit usually does more work than the exclusion.

What is the base location rule?

The idea that your employment is located where you report for duty. For crew that is the airport you sign on at, rather than wherever the aircraft happens to go. So somebody based at Heathrow is working in Britain for tax purposes even if most flying hours happen elsewhere.

Your roster tells you where your base is.

The destinations mostly do not matter.

How are work days counted for crew?

Carefully, because a day touching Britain usually counts. Arriving in the morning and departing at night still produces a day here under most readings. Crew who assume short turnarounds are invisible can accumulate far more British days than they expect across a year.

Keep the roster as your day record.

It is better evidence than memory.

Are you UK resident?

That depends on the statutory test, and crew often sit awkwardly within it. Days spent in the country are counted on the usual basis, with specific treatment for transit and for work days. Somebody rostered from a British base will usually be resident even with heavy flying.

Our guide to the statutory residence test covers the counting.

So run the test properly each year.

Does living near the base matter?

It matters a great deal for the residence question. Crew who keep a home within commuting distance of a British base look settled here on almost any measure, which usually makes bona fide residence straightforward to argue. Those crashing in shared crew flats between trips have a weaker story, because the ties that test looks for are thinner.

So a tenancy agreement is useful evidence.

Because permanence is what the test weighs.

What about cabin crew on short haul?

The principles are identical but the day counting is harsher. Short sectors mean more turnarounds touching Britain, so the British day count climbs quickly while almost no full days abroad accumulate. Short haul airline crew therefore find the physical presence route hopeless far more often than long haul colleagues do.

So bona fide residence is the realistic route.

Because the day arithmetic never works on short haul.

What if you are based abroad but live here?

That is the hardest pattern and it needs real care. Commuting to a base in another country can leave you taxed there on the duties and here on residence, with relief flowing by credit. The paperwork doubles and the cash flow suffers.

Our guide to apportioning UK employment income covers the split.

Commuting crew carry the worst admin.

What about per diems and allowances?

Treatment differs on each side, which is a common source of error. Britain may treat a subsistence allowance as non-taxable within limits, while America applies its own rules to the same payment. So a figure that disappears from one return can appear on the other.

Keep the allowance breakdown from payroll.

Do not assume both systems agree.

What about staff travel and perks?

Concessionary travel can be a taxable benefit, and the two systems value it differently. Britain has particular rules for airline staff travel, while America looks at whether the benefit is excludable under its own categories. Payroll should show what has been reported.

Our guide to benefits in kind on a US return covers the reporting.

Check the payslip against the return.

What about National Insurance?

It generally follows your base rather than the aircraft register. Crew based in Britain usually remain inside the British system, which protects the state pension record. That contribution also matters when an American charge is considered.

Our guide to certificates of coverage covers the agreement.

The flag on the tail is largely irrelevant.

Does American social security apply?

Only where you work for an American employer in a way that brings you inside it. Most crew employed by a British carrier and based here fall outside, with the totalisation agreement preventing double contributions. A certificate is the evidence if anybody asks.

Check your contract rather than your uniform.

Who employs you decides this.

Does the airline report you to anyone?

Your employer reports your pay to HMRC through payroll, as for any employee. It does not report to the IRS, because a British company has no reason to. So every figure on your American return comes from you rather than from an official document, which makes the payslip record more important than crew expect.

Because nobody cross checks it for you.

So keep every payslip for the full year.

Do American airline crew based here differ?

They do, and the position can reverse completely. Crew employed by a US carrier but based in Britain may stay inside American payroll withholding while also becoming UK resident, which produces tax deducted in the wrong country. Fixing that needs the withholding adjusted at source rather than reclaimed afterwards.

Our guide to working remotely for a US employer covers the payroll problem.

So raise it with payroll before the tax year starts.

What if you change base mid-year?

The year splits and both halves need working out separately. A move from a British base to one abroad can change the taxing country partway through, which affects residence, contributions and the exclusion tests. Keep the dates and the roster from both periods.

Our guide to split year treatment covers the British rule.

Base changes are the trigger to review.

What if you are furloughed or on long sick leave?

Pay continues to follow the base, but the day counting changes sharply. A period at home with no flying produces a long run of British days, which can tip residence and destroy an exclusion claim built on presence. Crew returning from extended leave should recheck both tests rather than assuming last year's answer still holds.

So a grounded year is a year to review.

Because the pattern that qualified you has gone.

Why is there no relief for airline crew?

Because the seafarers deduction was written for ships and never extended. Per GOV.UK guidance on that relief, it applies to work performed on a ship, and aircraft fall outside the definition entirely. Crew who assume a parallel exists are usually thinking of the maritime rule they heard about from a friend.

Our guide to the seafarers earnings deduction covers the maritime rule.

The difference is historical, not logical.

A worked example

Take an illustrative example. An American first officer is based at Gatwick, flying long haul, and sleeps abroad roughly half the year.

Britain taxes her salary because her base is here, and National Insurance comes out as normal.

She then tries the American exclusion and finds she cannot reach 330 qualifying days.

Her nights in hotels abroad count, but hours in international airspace do not, and the shortfall is about three weeks. So the credit has to carry the whole load instead.

Two mobile careers, two answers

Does the treaty have an article for crew?

It does, covering employment aboard aircraft operated in international traffic. The article generally gives taxing rights to one country rather than leaving the income split across every destination. For a British national it does useful work, which is the point of having it.

Our guide to the US UK tax treaty covers the structure.

It exists to stop a dozen countries claiming at once.

Does it help an American?

Far less, because of the saving clause. That clause lets America tax its own citizens broadly as though most of the treaty were absent, so the crew article protects a British colleague while leaving you with the full American charge. You get relief through credits instead.

Our guide to the saving clause covers the carve-outs.

Citizenship undercuts the article.

Can you use the earnings exclusion?

Sometimes, though the tests fight you. The physical presence route wants 330 full days in foreign countries across twelve months, and airspace is not a country. Crew flying long sectors lose hours to transit that a ground based colleague would bank easily.

Our guide to the foreign earned income exclusion covers both tests.

The bona fide residence route often suits better.

Which exclusion test works better for crew?

Bona fide residence, for somebody genuinely settled here. It looks at the nature and permanence of your life in Britain rather than counting days, which suits a person with a home, a base and a family here. The day counting route punishes exactly the pattern crew live with.

Our exclusion service covers the claim.

So settle the residence question first.

Does the housing exclusion apply?

It follows the earnings exclusion, so only if you qualify for that. Crew keeping a home near the base can claim housing costs on top of the salary exclusion. Company provided crew accommodation during layovers does not count towards it.

Our guide to the housing exclusion in London covers the limits.

Base city rates vary each year.

Does a company pension help?

Usually yes, and it is one of the better outcomes available. A UK workplace pension is recognised by the treaty, so growth inside it is generally left alone until drawn. For crew with limited scope for other planning, the pension does most of the work.

Our guide to UK pensions and US tax covers the position.

So contribute before reaching for anything exotic.

Do you still file in America?

Yes, every year, regardless of where you fly or how little you owe. Citizenship drives the filing duty, so a crew member who has not set foot in the States for a decade still files. Most owe little once credits are applied.

Our guide to US tax deadlines for expats covers the dates.

Filing and owing are different questions.

What does this cost airline crew in practice?

Usually time rather than tax, which is the one piece of good news. A British based crew member on a salary of £72,000 in 2025-26 pays UK income tax and National Insurance in the ordinary way, and the foreign tax credit normally wipes out the American charge entirely. What remains is the cost of preparing two returns every year for the rest of your career.

So the bill is usually nil and the admin is permanent.

But a year with a base change can produce real tax.

What about accounts in other countries?

Crew accumulate them easily, and they all count for reporting. A current account opened during a posting abroad still counts towards the American account reporting thresholds years later. Dormant accounts are the ones people forget to list.

Our guide to the FBAR covers the thresholds.

List them all, including empty ones.

What records should crew keep?

Rosters, payslips, the allowance breakdown and a record of your base. Those four answer nearly every question either authority asks. Rosters in particular are the only reliable evidence of where you actually were.

In our practice the roster settles most arguments.

Airlines purge them sooner than you think.

What happens if you leave flying?

The base rule disappears and ordinary employment rules take over. Moving into a ground role, management or another industry simplifies the position immediately, because the income stops being mobile. What does not change is the American filing duty, which continues for as long as you hold the passport.

Our guide to renouncing US citizenship covers the only exit.

So the paperwork outlasts the uniform.

How should airline crew handle both systems

1. Write down where your airline crew base sits for each part of the year.
2. Run the British residence test using the roster, not memory.
3. Test the bona fide residence route before counting days.
4. Count only days in actual countries for the presence test.
5. Check which contributions you pay and get a certificate if needed.
6. Reconcile allowances between the payslip and both returns.
7. Use the pension before any other planning.
8. List every foreign account, dormant ones included.

Mistakes and penalties we see with airline crew

The first is expecting a seafarers style deduction that aviation has never had.

The second is counting hours in the air as foreign days for the American test.

The third is forgetting that a short British turnaround still creates a day here.

The fourth is leaving accounts opened during foreign postings off the reporting.

How US UK Tax Accountants helps

We start from the roster and the base, because those two facts decide almost everything else about an aircrew return.

Then we test both exclusion routes properly rather than assuming the day count fails. Often the residence route rescues a year the presence test could not.

If you fly for a living and hold an American passport, get in touch before you file either return.

Last reviewed 22 October 2026. This article is general information and not personal tax advice, and the rules described change over time.

For the neighbouring question, Resident in both places at once, and the rule that decides walks through it in detail.