Cross-Border Tax Filing Deadlines: Canada and US

The Canadian and US filing deadlines are 15 days apart, and the extensions, penalties, and form-specific deadlines layer on top. A cross-border filer managing both returns, FBAR, Form 8938, T1135, Form 3520, and potentially state returns has a calendar with at least six independent deadlines, and missing any one of them triggers its own penalty. The purpose of this page is to put every deadline in one place.

What is the US filing deadline?

The US individual income tax return (Form 1040, 1040-NR, or 1040-SR) is due April 15 of the year following the tax year. If April 15 falls on a weekend or holiday, the deadline moves to the next business day.

Automatic extension for taxpayers abroad. US citizens and residents whose tax home is outside the US, or who are in military service outside the US, get an automatic 2-month extension to June 15 without filing any form. You attach a statement to the return explaining which condition applies. Interest on any balance owing runs from April 15, not June 15.

Extension by filing Form 4868. Filing Form 4868 by April 15 (or June 15, if the automatic abroad extension applies) extends the filing deadline to October 15. This is a filing extension only; it does not extend the payment deadline. Any tax owed is due by April 15 (or June 15 for the abroad extension), and interest accrues from that date.

Penalty for late filing. The failure-to-file penalty under IRC 6651(a)(1) is 5% of the unpaid tax per month, up to 25%. If the return is more than 60 days late, the minimum penalty is the lesser of $510 (2025, adjusted annually) or 100% of the tax due.

Penalty for late payment. The failure-to-pay penalty is 0.5% of the unpaid tax per month, up to 25%. Both penalties can run simultaneously, but the combined rate is capped at 5% per month for the first 5 months.

What is the Canadian filing deadline?

The Canadian T1 individual income tax return is due April 30 of the year following the tax year. If you or your spouse or common-law partner is self-employed, the filing deadline extends to June 15, but any balance owing still accrues interest from April 30.

No extension form exists in Canada. The CRA does not have a blanket extension mechanism like the US Form 4868. If you cannot file on time, you file late and pay the penalty, or you request relief under the taxpayer relief provisions (ITA 220(3.1)).

Penalty for late filing. 5% of the balance owing, plus 1% per month for up to 12 months. If the CRA has assessed a late-filing penalty in any of the three preceding years, the penalty doubles: 10% of the balance owing plus 2% per month for up to 20 months.

Departure year. For a non-resident filing a departure return, the deadline is still April 30 (or June 15 if self-employed). There is no special extension for non-residents filing departure returns.

What are the information-return deadlines?

Form	Due date	Automatic extension?	Late penalty
FBAR (FinCEN 114)	April 15	Yes, automatic to October 15	Up to $16,117 per account per year (non-willful); up to the greater of $161,170 or 50% of account balance (willful)
Form 8938	With the 1040 (April 15 or extended)	Follows the 1040 extension	$10,000; up to $60,000 for continued failure
Form 3520	With the 1040 (April 15 or extended)	Follows the 1040 extension	5% of reportable amount per month, up to 25%; minimum $10,000 for trusts
Form 3520-A	March 15	Extension to September 15 by filing Form 7004	5% of gross value of trust assets per year, minimum $10,000
T1135	With the T1 (April 30 or June 15)	Follows the T1 deadline	$25 per day, up to $2,500; $100 per day for knowing/gross negligence
T1134	With the T1	Follows the T1 deadline	$25 per day, up to $2,500

The FBAR automatic extension to October 15 is genuinely automatic: you do not need to file anything to get it. The April 15 deadline is the statutory date, and the automatic extension was added by regulation. If you file by October 15, you are on time.

Form 3520-A (Annual Information Return of Foreign Trust with a US Owner) has a March 15 deadline, separate from the 1040. This catches people who hold a Canadian trust (potentially including a TFSA or RESP, depending on classification) and think all their deadlines are April 15.

What is the filing order for cross-border returns?

In practice, most cross-border filers file the Canadian return first and the US return second, because the Canadian return determines the amount of Canadian tax paid, which feeds into the Form 1116 foreign tax credit on the US return. Filing the US return before the Canadian return requires estimating the Canadian tax, which creates a redetermination obligation under IRC 905(c) if the actual Canadian tax differs from the estimate.

The practical sequence:

1. Prepare the Canadian T1 return (due April 30).
2. Use the Canadian tax figures to prepare the US Form 1040 with Form 1116 (due April 15, but extended to October 15 with Form 4868 or automatically to June 15 if living abroad).
3. File the FBAR by October 15 (automatic extension).
4. File Form 8938, Form 3520, and other information returns with the 1040 (by the extended deadline).
5. File T1135 with the T1.

The US return is almost always filed on extension (October 15), because the Canadian return is due April 30 and the Canadian notice of assessment, which confirms the final Canadian tax, may not arrive until June or later. Filing the US return in September or October, after the CRA has assessed the Canadian return, produces the most accurate FTC and avoids redetermination issues.

What about state filing deadlines?

Most states follow the federal April 15 deadline and accept the federal extension (Form 4868) as a state extension. Some states require a separate state extension form. A few states have different deadlines (Hawaii is April 20; Iowa is April 30). Check the specific state.

What about estimated payments and instalments?

Estimated tax payments have their own quarterly deadlines, separate from the return deadline. US quarterly payments are due April 15, June 15, September 15, and January 15. Canadian instalments are due March 15, June 15, September 15, and December 15.

What should I do next?

Build a calendar with every deadline for your specific filing situation. The minimum for a cross-border filer is: April 15 (US estimated payment Q1, Form 4868 if needed), April 30 (Canadian T1 and T1135), June 15 (Canadian self-employed deadline, US abroad extension), October 15 (US 1040 on extension, FBAR). Add Form 3520-A (March 15) if you have a Canadian trust, and state deadlines if applicable.

• Form 8938 vs FBAR: do I file both?, the reporting forms and their thresholds
• Is my TFSA a foreign trust? Form 3520, the March 15 and April 15 trust deadlines
• Estimated tax payments and instalments, the quarterly payment calendar
• Streamlined filing for US citizens in Canada, when you have missed deadlines in prior years
• Gambling winnings cross-border, the June 15 NRA deadline for recovering US casino withholding

This guide is general information, not tax advice for your specific situation. Which points apply, and how, depends on your facts.