Tax Deadlines, Penalties and Interest

Two dates matter more than any others in Canadian tax: 30 April, when most returns are due and any balance owing must be paid, and 15 June, the later filing deadline for self-employed people. Missing them costs money — a penalty for filing late, and interest that compounds daily. This guide gives the deadline calendar, explains the penalties, and explains instalments, the quarterly payments some people must make during the year.

The main deadlines

For most individuals, the return for a tax year is due on 30 April of the following year. The 2025 return was due 30 April 2026; the 2026 return will be due 30 April 2027. Any balance owing for the year is due on the same day — filing and paying share the deadline.

Employers have an earlier deadline: T4 slips for a tax year must be issued by the last day of February after the year ends. For the 2026 tax year, that is 1 March 2027, because 28 February 2027 is a Sunday. If you are waiting for a slip, that is the date your employer must meet.

The self-employed deadline

If you or your spouse or common-law partner carried on a business in the year, your filing deadline is 15 June instead of 30 April. For the 2025 tax year, that was 15 June 2026. The extra six weeks are for filing only — they are not extra time to pay.

Any balance owing is still due 30 April, and interest starts on 1 May whether or not you have filed yet. If you are self-employed and you expect to owe tax, pay an estimate by 30 April and settle the exact amount when you file. The self-employed guide on this site explains the rest of the rules.

The late-filing penalty

If you owe tax and you file late, the CRA charges a late-filing penalty: 5% of the balance owing, plus 1% for each full month the return is late, up to a maximum of 12 months. On a $2,000 balance filed three months late, that is 5% plus 3% — $160.

The penalty applies only if you owe tax. If you are owed a refund, there is no late-filing penalty — but filing late can still delay benefits and credits that depend on your return. Repeated late filing can also bring a higher penalty: if the CRA charged you a late-filing penalty in any of the three previous years, the penalty can be 10% plus 2% per month, up to 20 months.

Interest on overdue tax

Interest on an unpaid balance starts the day after the payment deadline — 1 May for most people — and compounds daily at the CRA’s prescribed rate. The prescribed rate is reset every quarter, so it moves with interest rates generally. For the second quarter of 2026 it was 7% a year.

Interest also applies to penalties, and it keeps running until the balance is paid in full. That is why the CRA’s advice is consistent: file on time, and if you cannot pay in full, pay what you can by the deadline and contact the CRA about the rest. The refunds and amounts owing guide explains payment arrangements.

Instalments: paying during the year

Some people must pay their tax in instalments during the year instead of all at once in April. The CRA will send you an instalment reminder if you owed more than the threshold in the current and a prior year, or if it expects you to owe. Instalments are due four times a year: 15 March, 15 June, 15 September, and 15 December.

Instalments are common for self-employed people, landlords, and people with significant investment income — anyone whose tax is not mostly withheld from a paycheque. If you pay your instalments late or short, the CRA charges instalment interest. You can choose to pay the amounts on the CRA’s reminder, or calculate your own instalments from your expected income for the year.

Sources: Canada Revenue Agency, canada.ca; CRA, filing and payment deadlines; CRA, prescribed interest rates.