US and UK tax forms for Americans in the UK: the complete list

Americans in the UK deal with two tax systems and a separate US Treasury reporting regime. This list names each form you are likely to meet, what it does and when it matters, with links to our detailed guides. It is a map, not a checklist: most people need only a handful of these each year.

Core US returns

Form	What it is	When it applies
Form 1040	US individual income tax return	Every year your gross income exceeds the filing threshold for your status. Due 15 April; automatic extension to 15 June when living abroad.
Form 4868	Extension of time to file	Extends filing to 15 October. It extends filing, not payment.
Form 2350	Extension for people qualifying for the foreign earned income exclusion	When you need time to meet the 330-day or bona fide residence test before filing.
Form 1040-X	Amended US return	Correcting a return already filed.
Schedule B, Part III	Foreign accounts and trusts questions	Answered on the return by anyone with a foreign account or foreign trust.

US reliefs from double taxation

Form	What it is	Our guide
Form 1116	Foreign Tax Credit — offsets US tax with UK tax paid	Foreign Tax Credit
Form 2555	Foreign Earned Income Exclusion and housing exclusion	FEIE
Form 8833	Treaty-based return position disclosure	US–UK tax treaty

Foreign account and asset reporting

Form	What it is	Our guide
FinCEN Form 114 (FBAR)	Report of foreign accounts over US$10,000 in aggregate, filed with FinCEN, not the IRS	FBAR filing, late or amended FBAR
Form 8938	Statement of specified foreign financial assets (FATCA), filed with the return	Form 8938 thresholds
Form 8621	Passive foreign investment company (PFIC) return — UK funds, many ISA holdings	PFIC reporting
Form 3520 / 3520-A	Foreign trusts and large gifts or inheritances from non-US persons	Form 3520
Form 5471	US shareholders and officers of foreign corporations, such as a UK limited company	Form 5471
Form 8858 / 8865	Foreign disregarded entities and foreign partnerships (including some UK LLPs)	Ask us

Catching up and leaving

Form	What it is	Our guide
Form 14653	Certification of non-wilful conduct for the Streamlined Foreign Offshore Procedures	Streamlined procedures
Form 8854	Expatriation statement on renouncing citizenship or ending long-term green card residence	Exit tax

US identity and withholding forms

Form	What it is	Our guide
Form W-9	Certifies US status and taxpayer ID to a payer or bank	Exemption from FATCA reporting code
Form W-8BEN / W-8BEN-E	Certifies non-US status to claim treaty rates on US income	W-8BEN service
Form W-7	Application for an ITIN, often for a non-US spouse	Ask us

UK Self Assessment

Form	What it is	When it applies
SA100	Main Self Assessment return	Online deadline 31 January after the tax year ends on 5 April; paper deadline 31 October.
SA102 / SA103	Employment and self-employment pages	Income not fully taxed through PAYE, or a trade.
SA105	UK property pages	Rental income from UK property.
SA106	Foreign pages	Foreign income such as US interest, dividends, pensions or rent, and foreign tax credit relief.
SA108	Capital gains pages	Disposals above the reporting limits, including US shares.
SA109	Residence pages	Non-residence, split-year treatment and claims under the foreign income and gains regime.
UK property CGT return	60-day return for UK residential property disposals with tax due	UK capital gains for Americans
P85	Telling HMRC you have left or are leaving the UK	When you move abroad and want a refund or to close your PAYE record.
64-8	Authorising an agent to deal with HMRC	Lets an accountant talk to HMRC about your tax affairs.

How we use this list

When you first contact us, we map your income, accounts and history against these forms so the quote covers exactly what you need to file. Use the deadline calendar to see the dates that apply to you this year.