Almost everything that goes wrong in cross-border tax is fixed cheaply before the year closes and expensively after it. A treaty form signed before a payment goes out costs nothing. The same form produced in March, after 30 percent has been withheld, is a refund claim.
After that date the year is reported rather than decided.
In the order the deadlines fall. The full reasoning behind each one is in the dossier.
Every day this year, a third of last year’s, a sixth of the year before. 183 on the weighted total makes you a U.S. tax resident on worldwide income.
Run the countA closer connection claim needs fewer than 183 days this year. A treaty tie-breaker needs a treaty and a disclosure. Both are documentation exercises.
How holiday travel countsA W-8 generally expires on the last day of the third calendar year after signing. Forms signed in 2023 die on 31 December 2026, and 30% withholding resumes the next day.
A reduced rate applies when the documentation is already in the payer’s hands. Afterwards it is a refund claim, not an adjustment.
Management fees, licences, loans between a parent and its U.S. company. The written basis is expected to exist by the time the return is filed.
What the record looks likeCapital in, money out, loans, services, expenses paid on each other’s behalf. The annual information return is built from this, and the penalty for missing it starts at $25,000.
Company intakeA dividend on 30 December belongs to this year. The same payment on 2 January belongs to the next. This choice only exists while the year is open.
Peak-season stock, seasonal contractors and an agent who can sign are the facts that decide whether a foreign business is taxed here at all.
What peak season doesEstablished routes exist for late international filings. Every one of them is easier to use while nobody has written to you.
If a letter has arrivedA U.S. contractor and a foreign contractor take different forms, and one of them may carry withholding. Collect them while people still answer email.
Rental income can be taxed on the gross rent or, by election, on the net profit. If a sale is coming, withholding on the price can often be reduced before closing, but only in advance.
Property intakeJanuary and February are short months with hard dates in them. The table below is the one we work to.
For a calendar-year taxpayer. Dates move when they fall on a weekend or a federal holiday. An extension moves the filing date; it does not move the date tax is due.
| Date | What falls due | Who |
|---|---|---|
| 31 December 2026 | The tax year closes. W-8 forms signed in 2023 expire. | Everyone |
| 15 January 2027 | Final estimated tax payment for 2026 | Individuals paying estimated tax |
| 1 February 2027 | Contractor and wage statements to recipients (31 January is a Sunday) | Anyone who paid U.S. contractors or staff |
| 15 March 2027 | Partnership returns; annual withholding returns and their statements | Partnerships; anyone who withheld on payments to foreign persons |
| 15 April 2027 | Corporate returns, the foreign-owner information return, foreign account reports, individual returns with wages withheld | Companies; most individuals |
| 15 June 2027 | Individual returns with no wages subject to withholding; foreign corporations without a U.S. office | Non-residents filing personally |
Twelve items that are cheap to fix before the year closes and expensive afterwards: the day count, expiring treaty forms, undocumented intercompany charges, and the four deadlines that land between January and April.
Read the dossierA three-week visit is 21 days, and days in the current year count at full weight. How a holiday trip turns into U.S. tax residency on worldwide income, and which two exceptions are still open once it has.
Read the dossierFourth-quarter stock in U.S. fulfilment centres, seasonal contractors, and a returns wave that runs into February. The facts that decide whether a foreign seller is taxed in the United States are at their highest in Q4.
Read the dossierExpiring W-8 forms, related-party charges that need a written basis, the transactions that belong on the annual information return, and the timing decisions that stop being available once the year closes.
Read the dossierFor a non-domiciled giver, U.S. gift tax turns on what is given rather than who gives it: U.S. real estate and tangible property here are within reach, most financial assets are not, and the estate tax rules run the other way.
Read the dossierThis page is general information about U.S. tax mechanics, not advice on your own facts, and the dates are those for a calendar-year taxpayer.