CRA letters, decoded
Reviewed by EverStone CPA · August 2026
Quick answer: Most CRA letters are requests for information with a reply window, not accusations — but a few carry consequences that grow if nothing is sent. Find the one you are holding below. Each page explains what is being asked, how long you have, and what happens if it is ignored.
Work out which one you have
Letters rarely announce themselves clearly. Match what yours says to the middle column.
| Letter | What it says | What it means |
|---|---|---|
| Demand to file | The letter names a return and a date, and says filing is required | A return the CRA believes is outstanding. Ignoring it is what leads to an arbitrary assessment. |
| Personal return review | It asks for receipts or support for something you claimed | A review of your T1. Not an audit, but the deadline is real and the reply has to be precise. |
| Corporate return review | It refers to your T2 and asks questions about figures | The corporate equivalent. Usually one schedule or one number rather than the whole return. |
| GST/HST review | It asks for the records behind a GST/HST return | Support for input tax credits or reported sales. Documentation, not accusation. |
| You should be registered | It says you may have passed the GST registration threshold | The CRA believes your revenue crossed the small-supplier line and registration was required. |
| PIER report | It mentions a pensionable and insurable earnings review | Your T4 slips and your remittances do not agree. Fixing the wrong side makes it worse. |
| T4 mismatch | It says the slips filed do not match the return | Slip totals against reported figures. Common after a payroll software change or a late amendment. |
| Instalment reminder | It suggests an amount to pay by a date, and reads optional | The one letter that genuinely can be ignored in some cases — and expensive in others. |
What to do in the first hour
Almost every one of these gets worse slowly and better quickly. The order that matters:
- Find the deadline. It is usually a specific date rather than a number of days, and it is usually the only hard constraint in the letter.
- Read what is actually being asked for. Most of these want one document or one explanation, not a defence of your whole year.
- Do not send more than was asked. Volunteering unrelated records widens the question rather than closing it.
- Reply even if the answer is “I need longer”. Silence is what converts a request into an assessment made without you.
Why owner-managers get more of these
An incorporated owner files more returns than an employee does — a T2, a T1, GST/HST, payroll remittances and slips — and every one of them is a surface where the CRA’s records and yours can disagree. Most of these letters are the CRA noticing a difference between two things it already holds, which is why they so often resolve with a single document.
The exception is the demand to file. That one is not a question, and the cost of leaving it grows.
Send us the letter and we will tell you what it needs and what it will take. We quote the work in writing before starting.
Email us about a CRA letter