The IRS will confirm you are American, for a fee and a long wait

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

A UK payer has asked you to prove that America taxes you. Not that you hold a passport. That you are tax resident there.

Form 8802 is how you ask the IRS for that proof. What comes back, weeks later, is a certificate called Form 6166.

However, the application trips people up for dull reasons rather than difficult ones. The wrong year, a missing fee, a name that no longer matches.

Key takeaways

• Form 8802 is the application; Form 6166 is the certificate you receive.
• A user fee applies to each application, not to each copy.
• Allow around six weeks, and longer in the spring.
• You can apply for next year from 1 December of this one.
• The certificate names a single calendar year.
• A UK payer uses it to apply the treaty rate at source.
• Form 8802 proves residence; it does not claim any relief by itself.
• An unfiled return for the year will stall the application.

What is Form 8802?

An application, and nothing more. You tell the IRS who you are, which year you need covered and which country will see the result. You sign it under penalty of perjury. The IRS checks its own records and then issues the certificate, or writes back asking for more.

According to IRS guidance on the application, it is not a tax return and it claims nothing.

It is a request for confirmation.

What is Form 6166?

A one page letter on IRS headed paper. It states that you filed as a US resident for the year named on it. The letter carries no figures and no detail about your income. A foreign payer or tax authority reads it as evidence of residence and nothing else.

Each copy is an original, signed by the IRS.

Photocopies are often refused abroad.

Who actually needs one?

Anybody with UK source income who wants the treaty rate at source. That usually means an American back in the States drawing UK dividends, royalties or a pension. Equally, a US company billing a UK customer often gets asked for one before the invoice is paid.

Our guide to the US UK tax treaty covers what the rates actually are.

The payer asks because the payer carries the risk.

What does it cost?

There is a flat user fee for each application, currently $85 for an individual in 2025. One fee covers every copy you request on that form, so asking for six costs the same as asking for one. Pay it online before you send the application.

The payment confirmation number goes on the form itself.

A missing number is the commonest rejection.

How long does it take?

Plan on six weeks and hope for four. The queue lengthens sharply between February and June, when everybody applies at once. Per the IRS, you should allow at least 45 days before chasing, and chasing earlier achieves nothing useful.

Apply well ahead of the payment you are trying to protect.

There is no expedited route for an ordinary applicant.

Which year do you ask for?

The year the income arises, not the year you apply. A dividend paid in 2026 needs a certificate for 2026, even though you are asking in 2025. Getting this wrong is the single most common error, and it wastes both the fee and the wait.

Read the payer's request carefully before you fill anything in.

Some payers want the prior year instead.

Can you apply before you have filed?

Yes, from 1 December of the preceding year. You tick a box confirming you will file as a US resident, and the IRS issues on that basis. So a certificate for next year can be in your hands before the year has even started.

That is the route around the spring backlog.

The undertaking is a real one, so mean it.

What if you have never filed a US return?

The application will fail, because the IRS has nothing to confirm. An American abroad who has not filed needs to fix that first, and the catch-up route is usually the streamlined one. Only then does a residency certificate become available at all.

Our streamlined filing service handles the catch-up.

In our practice this is how many people discover they are behind.

How many copies should you request?

More than you think. Each payer wants an original, and a bank, a broker and a pension provider count as three. Since the fee covers the whole application rather than each certificate, extra copies are free at the point of asking.

Six is a sensible default for anybody with several payers.

Spares cost nothing and save a second wait.

Does the certificate expire?

It names one calendar year and speaks only to that year. There is no expiry date printed on it, but a payer will ask again once the year turns. Therefore most people with continuing UK income apply every December as a matter of routine.

Diarise it rather than waiting to be chased.

A lapsed certificate means withholding resumes.

What does a UK payer do with it?

They file it and reduce the tax they take. A UK company paying royalties to an American can apply the treaty rate once it holds evidence of residence. Without it the payer must withhold at the domestic rate and let you reclaim later, which is slow.

Our guide to US withholding tax for UK investors covers the mirror problem.

Relief at source always beats a refund claim.

Does a US citizen living in Britain need one?

Usually not, and this surprises people. If you live here you are UK tax resident, so HMRC is the authority that certifies you. An American in London asking the IRS for a residency certificate is normally asking the wrong government.

You want a certificate of residence from HMRC instead.

Citizenship and residence are different questions.

A worked example

Take an illustrative example. An American returns to Boston after eight years in London, leaving a UK company that still pays her royalties.

The company withholds at the UK domestic rate because it holds no evidence of where she now lives.

She applies in December for the following calendar year and asks for four copies at once.

The royalty arrives in March with the treaty rate applied. The alternative was a reclaim she would still be waiting on.

Two certificates, two authorities

What about UK dividends?

Britain takes no withholding tax from ordinary company dividends, so a certificate rarely matters there. The exception is a property income distribution from a REIT, which does suffer deduction. That is where a payer starts asking for evidence of residence.

Our guide to UK dividends on a US return covers the reporting.

Check what kind of distribution you actually hold.

What about UK royalties?

This is the classic case. A UK publisher or licensee must deduct tax from royalties paid abroad unless the treaty applies, and the treaty will not apply until they hold proof. So authors, musicians and software licensors meet this form more than anybody else.

Our guide to royalty income across the two systems covers the tax itself.

Agents will often chase the certificate for you.

Does it help with a UK pension?

It can, where the provider is deducting tax a treaty article would remove. A certificate supports the claim that America has the taxing right. In practice many providers want an HMRC form as well, so expect paperwork on both sides.

Our guide to moving back to the US covers the wider repatriation.

Start the process months before the first payment.

Does it cover state tax?

Not at all. The certificate speaks to federal residence and says nothing about California, New York or anywhere else. A state can still regard you as resident while the IRS certificate sits in a drawer, and the two questions are answered separately.

Our guide to state tax after you leave covers that risk.

Nothing a state does changes the federal letter.

What if you are resident in both countries?

Then the treaty tie-breaker decides, and the answer is not automatic. Where it lands on Britain, the IRS may still issue a certificate on the basis of your filing, which can confuse a payer. Resolve the tie-breaker before you apply.

Our guide to the statutory residence test covers the British half.

Two certificates pointing opposite ways helps nobody.

Do you need an ITIN first?

You need a number the IRS recognises, which for most people is a social security number. A spouse or dependant without one may need an ITIN before any application succeeds. Applying without a valid number simply produces a rejection letter weeks later.

Our guide to ITIN applications from the UK covers the process.

Sort the number out first, always.

Can a company apply?

Yes, and the mechanics are similar. A US corporation, partnership or LLC can request certification for its own treaty claims, though the fee and the signature rules differ. A disregarded entity applies in the name of its owner rather than its own.

Our guide to Form 5472 for UK owners of US LLCs covers the related reporting.

Get the signatory right or it bounces.

What if your name has changed?

Match the IRS record, not your passport. A name changed by marriage or deed poll must reach the Social Security Administration before the IRS will recognise it. Until the records agree, the application fails on identity grounds and the fee is simply spent.

Update the number first, then apply.

This delay catches newly married applicants constantly.

Can you fix a rejected application?

Often, and quickly. The IRS writes explaining what is missing, and a short reply usually revives the file without a second fee. Ignoring that letter is what forces a fresh application, so answer it the week it arrives.

Keep the original payment reference to hand.

Most rejections are clerical rather than substantive.

What if the payer refuses it?

Some do, usually because their own compliance team wants a different document. Ask precisely what they need in writing before reapplying. Where they will not budge, the fallback is to suffer the deduction and reclaim it from HMRC afterwards.

Our guide to overpayment relief for US filers covers the reclaim.

A reclaim is slower but it is not lost money.

Does it replace Form 8833?

No, they do different jobs. The certificate proves where you are resident, for a foreign payer. Form 8833 discloses a treaty position to the IRS on your own return. One faces outward and the other faces inward, and plenty of situations need both.

Our guide to disclosing a treaty position covers the disclosure.

Neither is a substitute for the other.

Does it prove anything to the IRS?

Nothing it did not already know. The certificate is generated from your filing history, so it confirms the IRS view back to you. It carries no weight in an American dispute and adds nothing to your own return.

Its whole value sits abroad.

Treat it as a document for other people.

What if you move mid-year?

A part year is awkward, because the certificate speaks to a whole calendar year. Somebody who leaves Britain in June may file a dual status return, which complicates the confirmation. Expect questions, and expect to explain the position in writing.

Our guide to dual status returns covers that year.

Timing a move around a year end simplifies everything.

Does the treaty saving clause affect it?

Not the certificate itself, though it shapes what the certificate buys you. The saving clause lets America tax its citizens as if much of the treaty were not there. So evidence of residence may open a foreign relief while changing nothing at home.

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

Read the relevant article before assuming relief.

How far ahead should you apply?

December, for the year ahead, every year. That avoids the spring queue entirely and puts the certificate in your hands before any payment is due. Anybody with recurring UK income should treat it as an annual diary entry rather than a reaction.

Build it into the same routine as your return.

The fee is small set against a reclaim.

What records should you keep?

The payment reference, a copy of what you sent, and every certificate you receive. Payers lose originals with some regularity, and a scan of yours settles the argument. Keep them by year so the current one is easy to find.

Note which payer holds which original.

That list saves a reapplication later.

How to apply for Form 8802

1. Confirm which country and calendar year the Form 8802 application must name.
2. Check you have filed, or will file, as a US resident for that year.
3. Make sure your name matches the Social Security record.
4. Pay the user fee online and keep the confirmation number.
5. Complete Form 8802 and enter that payment reference.
6. Ask on the Form 8802 for several original copies rather than one.
7. Allow at least 45 days before chasing anything.
8. Send each certificate to the payer that asked for it.

Mistakes and penalties we see with Form 8802

The first is requesting the wrong year, which wastes the fee and the wait together.

The second is applying with unfiled returns behind you, which stalls the file completely.

The third is asking for a single copy, then queueing again when a second payer asks.

The fourth is applying in March, when the queue is at its longest and the money is already due.

How US UK Tax Accountants helps

We check first whether you need an American certificate at all, because people living in Britain usually need the British one instead. That single question saves a wasted application.

Then we file it with the return history that supports it. Our treaty relief service covers the claim behind it.

If a UK payer is withholding from you right now, get in touch before the next payment date.

Last reviewed 20 October 2026. This article is general information and not personal tax advice, and fees and processing times change.