// myloanmath reference
Financial Calendar
Tax filing dates, quarterly payment deadlines, contribution cutoffs, and when your paperwork actually shows up — for the United States and Canada.
The weekend rule, and the one place it surprises people
Both the IRS and the CRA follow the same basic principle: if a deadline falls on a Saturday, Sunday, or legal holiday, it moves to the next day that isn't one of those. That's why the W-2 deadline in this calendar reads February 1, 2027 rather than the usual January 31 — January 31, 2027 is a Sunday. The same shift pushes the Canadian T4 slip deadline from February 28 to March 1, 2027.
The part that trips people up is that the shift only applies when the deadline itself lands on a non-business day. April 15, 2027 is a Thursday, and Washington DC's Emancipation Day holiday falls the very next day, Friday April 16. A holiday sitting one day after the deadline does nothing — the filing deadline stays April 15, 2027. In years where April 15 falls on a weekend and the holiday lands on the following Monday, the deadline can slide two or three days instead, which is where the widely repeated "tax day moves around" idea comes from.
Filing extensions are not payment extensions
This is the single most expensive misunderstanding on the calendar. In the US, a Form 4868 extension moves your filing deadline from April to October, but any tax you owe is still due in April — interest and the failure-to-pay penalty start accruing the day after. In Canada, self-employed filers get until June 15 to file, but any balance owing is still due April 30. In both countries the practical move when you're not ready is the same: estimate what you owe, pay it by the earlier date, then take the extra time to finish the paperwork.
Contribution deadlines don't all work the same way
Retirement contribution cutoffs split into two groups, and mixing them up is common. Contributions that run through payroll — 401(k) and 403(b) employee deferrals — have to happen inside the calendar year, so December 31 is a hard stop. Contributions you make yourself get a grace period into the following year: IRA and HSA contributions count toward a tax year right up to that year's filing deadline in April, and Canadian RRSP contributions count for the prior tax year up to roughly 60 days into the new one. TFSA room is different again — new room simply appears every January 1 and unused room carries forward indefinitely, so there's no deadline to miss.
Where these dates come from
US dates for 2026 follow IRS Publication 509 (Tax Calendars, for use in 2026) and the statutory due-date rules it sets out. US dates falling in 2027 are derived from those same statutory rules — the 15th day of the fourth month for individual returns, the 15th day of the 4th, 6th, and 9th months plus the month after year-end for estimated payments — with weekend and DC-holiday shifts applied. The IRS publishes its 2027 calendar in late 2026, so treat the 2027 rows as the rule correctly applied rather than as dates copied from a published IRS calendar, and re-check them once Publication 509 for 2027 is out.
Canadian dates follow the CRA's published due dates for individuals and its RRSP and instalment deadline pages. As of this page's last update the CRA's own page still covers the 2025 tax year, so the 2026-tax-year rows here apply the same published rules — April 30 for filing and payment, June 15 for self-employed filing, 60 days into the new year for RRSP contributions — with weekend shifts applied.
One date on this page is genuinely unsettled and is flagged as such in the calendar: the closing date of the ACA Marketplace open enrollment period for 2027 coverage. Sources currently disagree between December 15, 2026 and January 15, 2027, because a federal rule change shortening the window is under appeal. The opening date of November 1, 2026 is consistent across sources. Check HealthCare.gov for the current end date before relying on it — this calendar deliberately doesn't pick a side.
This is a reference for planning, not tax advice, and it doesn't cover state or provincial deadlines, estate and gift tax dates, trust returns, or business filings beyond the two entity deadlines listed. Deadlines can also shift for federally declared disaster areas. Confirm anything consequential against the IRS or CRA directly.
Frequently asked questions
What happens if a tax deadline falls on a weekend?
It moves to the next day that isn't a Saturday, Sunday, or legal holiday. That's why the W-2 deadline is February 1, 2027 rather than January 31 — January 31, 2027 is a Sunday.
Does an extension give me more time to pay?
No. An extension moves the filing deadline only. Any balance owed is still due on the original April date in the US, and April 30 in Canada, with interest and penalties running from the day after.
When is the last day to contribute to an IRA for a given tax year?
The tax filing deadline for that year, not including extensions — so April 15, 2027 for the 2026 tax year. This differs from 401(k) contributions, which must come out of payroll by December 31.
Why do the quarterly estimated tax dates look unevenly spaced?
Because they are. The US quarters run April 15, June 15, September 15, and January 15 — a two-month gap, then three, then four. They follow the 15th day of the 4th, 6th, and 9th months of the tax year plus the month after it ends, which doesn't produce even quarters.