Filing deadlines for the 2026 tax year, late-filing penalties and interest, instalments, over-contribution traps, how to fix a return and where to check the rules.
Most tax pain in Canada comes from avoidable mistakes: filing late when a balance is owing, missing instalment reminders, over-contributing to a TFSA or RRSP, forgetting a slip, or letting an objection deadline pass. This section covers each of those with the dates for the 2026 tax year, how the penalty is calculated and what to do if it has already happened.
The mistakes and sources hub lists the official places to check: the Canada Revenue Agency, Revenu Québec, the Department of Finance, the Justice Laws website for the Income Tax Act, and the Taxpayers' Ombudsperson. Rules on penalties and relief are applied case by case; if a large amount or several years are involved, talk to a professional before you contact the CRA.
Deadlines, Penalties and Official Sources
How to correct a filed return (Change my return, ReFILE, T1-ADJ), the 90-day objection deadline, appeals to the Tax Court, CRA review letters and requests for taxpayer relief.
Deadlines, Penalties and Official Sources
How the CRA's late-filing penalty (5% + 1% a month, or 10% + 2% for repeat filers) and daily interest are calculated, with worked examples, and how to ask for relief.
Deadlines, Penalties and Official Sources
How the 1% monthly tax on excess TFSA, RRSP and FHSA contributions works, the $2,000 RRSP buffer, worked examples, the forms to file and how to ask the CRA for a waiver.
Deadlines, Penalties and Official Sources
Every personal tax deadline for the 2026 tax year in Canada: December 31 planning dates, the March 1, 2027 RRSP deadline, April 30 and June 15 filing, instalments and Quebec.
Deadlines, Penalties and Official Sources
The personal tax mistakes that most often lead to penalties, interest or lost benefits in Canada, how to fix each one, and the official CRA and Revenu Québec sources to rely on.
Deadlines, Penalties and Official Sources
Who must pay quarterly tax instalments ($3,000 net tax owing, $1,800 in Quebec), the March, June, September and December dates, three calculation options and a retiree example.
