US Expat Tax Return Documents Every Preparer Needs

A US expat tax return is only as accurate as the documents that back it — and the document set is materially wider than a domestic return. Beyond the wages, dividends, and mortgage-interest statements a preparer needs for any 1040, an expat return typically requires proof of physical presence in a foreign country for the Foreign Earned Income Exclusion, foreign employer payslips or annual statements, foreign tax assessments or withholding vouchers for the Foreign Tax Credit, brokerage year-end statements sufficient to classify each holding as a PFIC or non-PFIC, foreign bank statements at both year-end and the highest-balance day of the year for FBAR, and pension or retirement-plan disclosures for FATCA reporting on Form 8938. This piece walks the full document list a US expat tax preparer will ask for, form by form, so the intake goes cleanly and no filing is missed. Nothing here is tax advice; anyone with a specific fact pattern should consult a licensed cross-border adviser.

The context comes from citizenship-based taxation. As the United States country page sets out, US citizens and green-card holders are taxed on worldwide income regardless of where they live, with a top federal marginal rate of 37% for 2026, state taxes up to 13.3% additional, and a Foreign Earned Income Exclusion capped at $132,900 for 2026. Every credit, exclusion, or exception that reduces this liability depends on documentation the taxpayer can produce on request — the IRS has statutory authority to disallow the credit or exclusion in the absence of substantiation.

The document set at a glance

The categories below map to the specific forms a US expat tax preparer will assemble. Not every taxpayer needs every category — a wage earner with a single foreign employer and one bank account has a much shorter list than a business owner with a foreign corporation and a multi-country pension history. The categories are cumulative: an expat who moves up the complexity tiers described in the 2026 fee benchmark keeps everything from the earlier tiers and adds more.

Passport stamps and travel calendar (physical presence)

The FEIE has two qualification tests — physical presence and bona fide residence — and both require documentary proof. The physical presence test requires 330 full days in a foreign country or countries during any 12-month period; a full day runs midnight to midnight, and travel days over international waters do not count toward the total. The 12-month period does not need to be a calendar year, and a preparer will often optimise the window to capture the highest excluded income.

The core documents for this test are the taxpayer's passport with entry and exit stamps, and a written travel calendar reconciling every departure and arrival. Airline itineraries, boarding-pass emails, and app-based travel logs are useful backup. Preparers ask for the passport itself, typically photographed or scanned page by page, because Schengen and other regional agreements have progressively reduced stamping, and the taxpayer's memory of borderless trips is systematically inaccurate. A single unstamped trip that pushes the total below 330 full days invalidates the FEIE for that year. Where stamps are missing, preparers reconstruct from card statements, phone location data, or foreign employer travel records.

Bona fide residence documentation

The alternative qualification path — bona fide residence — requires being a bona fide resident of a foreign country for an uninterrupted period that includes an entire tax year. The documentation is quite different: residence permit or visa, foreign tax residency certificate, housing lease with the taxpayer's name, utility bills in the taxpayer's name, foreign tax return filed as a resident, evidence of local ties such as bank accounts, driver's licence, and community memberships, and often correspondence showing intent to remain indefinitely rather than for a defined stay. A bona fide residence claim by someone who filed their host country's tax return as a non-resident is functionally impossible to sustain.

Foreign employer statements (foreign earned income)

The FEIE, foreign housing exclusion, and Form 2555 all depend on quantifying foreign earned income separately from investment income. Foreign employers typically issue an annual pay summary at year-end — the format varies by country (a UK P60, a German Lohnsteuerbescheinigung, an Australian PAYG payment summary, a French bulletin de salaire récapitulatif) — and a preparer needs the annual document rather than 12 monthly payslips, though the monthly payslips are useful for reconciliation.

The specific items required are gross wages in local currency, foreign income tax withheld, foreign social security or equivalent contributions withheld, employer-paid pension or benefit contributions (some of which are US-taxable even when non-taxable locally), and any equity compensation vested during the year. Housing allowances paid by the employer are treated as foreign earned income and included in the FEIE base. Any non-cash benefits — a company car, employer-provided housing, employer-paid schooling for dependents — are also income for US purposes even if the host country excludes them. The salary in foreign currency analysis covers how currency conversion is handled across the year.

Foreign tax vouchers and assessments (Foreign Tax Credit)

The Foreign Tax Credit — claimed on Form 1116, often in multiple copies because credits are calculated separately by income category — requires proof that foreign tax was actually paid or accrued. The documents that establish this vary by country and income type:

• Foreign income tax return as filed, in the local language, with a translation summary of the tax liability and any refund.
• Notice of assessment issued by the foreign tax authority, which is the authoritative statement of tax owed and paid.
• Foreign employer year-end statement showing income tax withheld at source.
• Withholding vouchers or dividend statements from foreign brokerages showing tax withheld on dividends and interest.
• Property tax bills paid abroad, if the taxpayer is crediting foreign real estate taxes.
• Bank confirmation of tax payments, particularly for quarterly installments or self-assessed taxes.

The FTC claim requires the tax to be a legal and actual liability. Estimated taxes not yet finally assessed can be claimed on an accrual basis, but the preparer will want to see the estimate calculation as well as the underlying liability. Unused foreign taxes carry forward for a defined window under current law — a preparer inheriting an expat file from another firm will ask for prior-year Form 1116s to reconstruct the carryover schedule, discussed in the FEIE versus Foreign Tax Credit analysis. Verify current carryover rules with a licensed adviser, as they can change.

Brokerage annual statements (PFIC classification)

Passive Foreign Investment Company classification is where documentation matters most and is most commonly missing. Most non-US mutual funds and ETFs held by a US person are PFICs, and each PFIC generally requires its own Form 8621 each year — see the PFIC rules explainer. The default excess-distribution regime taxes gains and distributions at the top marginal rate of 37% plus a compounding interest charge, and Qualified Electing Fund or mark-to-market elections require specific fund-level information.

The documents needed for each foreign brokerage account are:

• Annual consolidated brokerage statement listing every holding with year-end market value, cost basis, and all transactions during the year.
• Distribution history for the year — ordinary dividends, qualified dividends (rarely applicable for PFICs), capital gain distributions, return of capital.
• Fund fact sheet or Key Investor Information Document for each fund holding, sufficient to identify the fund as a mutual fund, ETF, investment trust, or something else.
• Annual PFIC statement from the fund manager where the fund issues one — these are essential for a QEF election, which requires the fund's ordinary earnings and net capital gain figures on a US tax basis. Most non-US funds do not issue these, which forces the default excess-distribution regime.
• Prior-year Form 8621 filings if any, to track basis and elections.

Foreign life-insurance wrappers, unit-linked policies, and pension pots that hold investment funds also require PFIC lookthrough analysis, and the underlying fund statements need to be supplied. Preparers cannot classify PFICs from a line-item holding name alone.

Foreign bank statements at year-end and highest-balance day (FBAR)

The FBAR — FinCEN Form 114, filed separately from the tax return — applies to any US person whose aggregate foreign financial account balances exceeded $10,000 at any point during the calendar year. The threshold is aggregate, not per-account: five accounts each holding $3,000 briefly during the year trigger a filing requirement because the aggregate crossed $10,000 even momentarily. The FBAR and FATCA guide covers the mechanics.

For each foreign financial account — checking, savings, brokerage, mutual fund, foreign pension in some cases, cash-value life insurance in some cases, and any account over which the taxpayer has signature authority — the preparer needs:

• Account number, financial institution name, and full mailing address of the institution.
• Type of account and whether jointly owned, with the co-owner's identification if applicable.
• The maximum balance during the year, converted to US dollars using the Treasury Reporting Rate of Exchange for the last day of the calendar year. The FBAR uses that specific end-of-year rate, not the day-of-max rate.
• A statement or screenshot documenting the maximum balance day so the figure can be substantiated on audit.

The maximum-balance day is the item most often missing at intake. A taxpayer who supplies only year-end statements has given the preparer enough for Form 8938 but not for FBAR — the FBAR requires the highest balance at any point in the year, which for accounts with a lump-sum inflow (sale of a house, receipt of an inheritance, bonus payment) can be many multiples of the year-end figure. A short pull of monthly statements is usually sufficient to identify the peak day.

Form 8938 documentation (FATCA)

FATCA reporting on Form 8938 overlaps heavily with FBAR but is not identical. Form 8938 is filed with the tax return, uses higher thresholds (for taxpayers living abroad, generally $200,000 in aggregate specified foreign financial assets at year-end or $300,000 at any time during the year for single filers; $400,000 or $600,000 respectively for married filing jointly), and covers a wider asset set including foreign stock held directly, foreign partnership interests, and some foreign pension interests. Verify current thresholds with a licensed adviser as of 2026.

The documentation is similar to FBAR — year-end statements for every foreign financial account, plus statements for foreign non-account assets — but Form 8938 additionally requires the tax items generated by each account (interest, dividends, capital gains) mapped to the specific lines on Schedule B, Schedule D, and the like where they appear on the return. The year-end balance is the relevant figure for the reporting threshold; the maximum during the year is required only for the high-balance column on the form itself. Taxpayers whose year-end balances sit just under the thresholds should supply year-end statements anyway — a preparer needs to confirm the threshold was not exceeded.

Foreign pension and retirement-plan disclosures

Foreign pensions are the area where US expat returns most often diverge from the taxpayer's assumptions. A UK personal pension, a German Riester or Rürup plan, an Australian superannuation account, a Swiss Pillar 2 or 3 account, or a Canadian RRSP each has its own US tax treatment — some are treated as employees' trusts, some as grantor trusts, some as PFICs at the underlying investment level, and treaty positions differ country by country. The foreign pension US tax treatment analysis works through the categories.

The documents a preparer needs for each foreign pension are:

• Annual plan statement showing year-end value, contributions during the year (both employee and employer), investment earnings, and withdrawals.
• Plan documents or scheme rules sufficient to establish the plan type — employer-sponsored versus personal, defined benefit versus defined contribution, tax-qualified locally versus not.
• Investment holdings within the plan, in enough detail to identify PFICs held inside the wrapper.
• Treaty article citation where the taxpayer intends to claim treaty relief on contributions or earnings.
• Prior-year Form 8938 entries for the same plan, to maintain consistency across years.
• Form 3520 and 3520-A filings where the plan is treated as a foreign grantor trust — this varies by plan type and preparer judgment.

Foreign pension contributions are usually not deductible on the US return even when they are locally, and employer contributions may be immediately taxable to the US person depending on plan type. Getting these entries right requires the plan documentation up front rather than a mid-year reconstruction.

US-source documents still required

Because the US taxes worldwide income, all US-source items also need to be reported on the same return. Preparers ask for the standard domestic document set alongside the foreign one: W-2 from any US employer during the year, 1099-INT and 1099-DIV from US banks and brokerages, 1099-B for capital gains transactions, 1099-R for US retirement plan distributions, K-1s from any US partnership or S-corp interests, SSA-1099 for Social Security benefits, 1098 for US mortgage interest on any retained US property, and 1098-T for any education expenses. Taxpayers who left a US brokerage account open after moving abroad continue to receive 1099s and must report those items even if the account has been dormant.

Additional documents by fact pattern

Several situations add specific documentation requirements:

• Foreign rental property. Rental income and expenses in local currency, depreciation schedule (US depreciation on foreign residential real property is a long-life method), foreign property tax paid, mortgage interest paid, and any local tax filings related to the rental. The rental property abroad analysis covers the treatment.
• Foreign business ownership. Financial statements of the foreign entity for the tax year, cap table showing ownership percentages of all shareholders, foreign corporate tax return, and any distributions or loans between the entity and its US owners. Form 5471 is the reporting vehicle — see the GILTI guide.
• Foreign gifts or inheritances above thresholds. Gifts from a foreign individual aggregating more than $100,000 in a year, or from a foreign entity above a lower indexed threshold, trigger Form 3520. The preparer needs donor identification, relationship documentation, date and value of each transfer, and any inheritance grant of probate or equivalent. The Form 3520 explainer covers this.
• Sale of a foreign home. HUD-1 or foreign equivalent settlement statement, original purchase documentation, receipts for capital improvements, and any local tax paid on the sale. Section 121 principal-residence exclusion may apply. See selling a foreign home.
• Streamlined filing. Six years of foreign bank statements at year-end and maximum, three years of foreign income documentation, and a written narrative reconstructing why prior filings were missed. The streamlined filing analysis details the package.
• State residency question. Documentation of moves out of a state that does not readily release residents — California, New York, New Mexico, Virginia. See the California residency audit analysis.
• Married to a non-US spouse. Passport of the non-US spouse if a Section 6013(g) election is being made, ITIN application documentation, and separate foreign income documentation for the spouse. See married to a foreign spouse.

Currency conversion evidence

Every foreign-currency figure on a US return has to be converted to US dollars. The IRS accepts the yearly average rate for income items spread across a year, the day-of-transaction rate for one-off items, and the Treasury year-end rate for FBAR balances. Preparers usually apply these mechanically, but the taxpayer's records need to support the conversion — either monthly account statements from which conversion rates can be derived, or a schedule of transactions with dates. Ad-hoc conversions using retail bank rates from mid-year are the most common source of small errors that accumulate across a return.

Common intake gaps

Across expat intake, the same items go missing repeatedly:

• Maximum balance day statements for FBAR. Year-end alone is not sufficient.
• Passport pages showing stamps. A scanned bio page is not enough.
• Foreign tax return as filed, in the local language. A one-line summary of tax paid is often not adequate substantiation.
• Fund fact sheets for foreign brokerage holdings. Preparers cannot classify PFICs from a line-item name alone.
• Pension plan rules documents. A year-end value statement without the underlying scheme rules leaves the US treatment unresolved.
• Prior-year returns and workpapers. Foreign Tax Credit carryovers, PFIC basis, and pension basis all rely on continuity across years.

Supplying these on intake — rather than after a request several weeks in — is the difference between a smooth engagement and one that runs late into the filing calendar. The preparer selection guide covers how firms typically structure their intake questionnaires and what to watch for in engagement letters.

A note on retention

US expat returns are supported by documentation kept by the taxpayer, not the preparer, so retention discipline matters. The IRS statute of limitations for a standard tax return is three years from filing, extended to six years for substantial understatements, and open indefinitely for fraud or unfiled returns; the FBAR retention requirement is separately five years. Foreign tax authority statutes vary and can be longer. As of 2026, verify current retention rules with a licensed cross-border adviser — the practical rule most specialists recommend is to retain the full document set for at least seven years, with pension and PFIC basis documentation retained for the life of the position.

Where to go next

For the full US filing framework and rates behind these documents, see the United States country page. The preparer selection guide and the 2026 fee benchmark cover who to send the documents to and what it should cost. On specific filings, the FBAR and FATCA guide, the PFIC rules explainer, and the FEIE versus Foreign Tax Credit analysis go deeper. On foreign pensions, see foreign pension US tax treatment. On remediation for missed filings, the streamlined filing analysis covers eligibility. General questions are collected in the FAQ.