A CRA notice of assessment is the Canada Revenue Agency's summary of how it processed your return. A notice of reassessment follows when the CRA changes an assessed return, whether because it found a mismatch, finished a review or audit, or processed a change you asked for. Reading the notice carefully, and comparing it line by line with the return you filed, is the first defence against a missed refund or an unexpected balance. This guide covers what the notice contains, how to correct it, and which time limits apply.
How to read your CRA notice of assessment
The CRA says a notice of assessment (NOA) is the summary of the calculated amounts for your income tax and benefit return. It has these parts:
| Section | What it shows |
|---|---|
| Notice details | The last four digits of your SIN or TTN, the tax year and the issue date |
| NETFILE access code | An 8-character code used to file future returns electronically |
| Account summary | A refund, an amount due or a nil balance |
| Tax assessment or reassessment | Key line numbers and amounts, with an explanation of any changes |
| Registered plan statements | RRSP deduction limit and contribution room, Home Buyers' Plan, Lifelong Learning Plan and First Home Savings Account room, where they apply |
The notice is usually available in your CRA account once the return is processed. If you gave the CRA an email address and did not choose letter mail, you receive an email that mail is waiting; otherwise it is mailed. For a paper copy, you must ask the CRA. Authorized representatives can open a client's notice through their representative account. Processing takes longer if you file late, the CRA reviews your return or you file a multiple, bankruptcy or deceased taxpayer return, and the CRA says non-resident returns can take up to 16 weeks.
What is a notice of reassessment, and why did I get one?
The CRA sends a notice of reassessment (NOR) only if changes are made to your assessed return, right after the reassessment is complete. Common causes are a mismatch with slips such as T4 or T5 information, a review in which you were asked for receipts (see CRA information requests and audits), an audit result, or an adjustment you requested.
What should I do first?
- Open the notice and note the date. Time limits run from the notice date.
- Compare it to your return. Check income slips, deductions, credits and registered plan amounts, and see the line-by-line detail under Tax returns in your CRA account.
- Decide whether information is missing or wrong. If you left something out or entered it incorrectly, correct it.
- Change the return. The CRA offers Change my return in your CRA account (processed within two weeks, per the CRA) or ReFILE through certified software. By mail, send Form T1-ADJ with supporting documents; the CRA lists a 19-week processing target. Requests for years beyond the normal three-year reassessment period can take up to 35 weeks.
- If the information is complete but you disagree, object. Register a formal dispute online or file Form T400A. See CRA objections and appeals.
- Pay or arrange payment. Interest accrues on an unpaid balance. See CRA collections and payment arrangements.
- Keep records. Keep receipts and supporting documents for at least six years in case your return is selected for review.
If the CRA changed your claim after a review and you have more information, it says it will accept new submissions and review your claim again for a possible adjustment.
How long can the CRA reassess my return?
The Income Tax Act sets a normal reassessment period. For an individual it ends three years after the earlier of the day the CRA sent the notice of original assessment or a notice that no tax is payable. For mutual fund trusts and corporations that are not Canadian-controlled private corporations the period is four years.
The CRA can go beyond the normal period in listed situations. It may reassess at any time if the taxpayer made a misrepresentation attributable to neglect, carelessness or wilful default, or committed fraud in filing the return. It may add three years where the reassessment results from a transaction with a non-resident person with whom the taxpayer was not dealing at arm's length, and the Act has related rules for foreign affiliates. A taxpayer can also file a waiver before the normal period ends. For cross-border filers, dealings with a related non-resident, such as a family company in the US or India, can keep a year open for longer.
What are the deadlines to respond?
| Item | Time limit as published (2026) |
|---|---|
| Register a formal dispute (individual) | The CRA's notice pages say 90 days from the date of the notice; Guide P148 gives the later of 90 days or one year after the filing deadline |
| Corporation objection | 90 days from the notice date |
| Tax Court of Canada appeal | 90 days from the notice of confirmation or reassessment, or if the CRA has not decided within 90 days of the objection |
| Request a refund beyond the normal three years | Discretionary; the CRA considers requests where the result would have been allowed had the return been filed on time |
| Taxpayer relief for penalties and interest | Within 10 calendar years |
Treat 90 days as your working limit and file earlier if you can; confirm the exact rule with your Canadian CPA.
How the other countries compare
| Authority | Document | Typical clock | Reading |
|---|---|---|---|
| CRA | Notice of assessment or reassessment | 90 days to dispute (individual detail above) | This page |
| IRS | Notice of deficiency | 90 days (150 outside the US) to petition the Tax Court | IRS first steps |
| India | Intimation or notice through e-proceedings | Stated on the notice | India notices overview |
If you are a US citizen living in Canada, an NOR can change the amounts you use for your US return and foreign tax credit; see US citizens living in Canada and file an amended US return when the numbers change.
A worked example
Nikhil, a newcomer from Hyderabad living in Mississauga, files his first T1 in April 2026 and claims $5,000 of moving expenses. In August he receives a notice of reassessment that removes the claim because the CRA did not receive receipts. He compares it to his return, locates the moving company invoice and airfare receipts, and uploads them in response to the CRA's review request. The CRA says it will review new submissions again. If the CRA still disallows the claim after reviewing the receipts, and his information is complete, he can then register a formal dispute within the time limit. The figures are hypothetical.
Mistakes to avoid
- Ignoring a notice because it shows a refund. A reassessment can reverse it.
- Treating the NETFILE access code as a password.
- Waiting for the CRA call. Respond in your CRA account or in writing.
- Assuming a three-year-old return is closed when misrepresentation or foreign transactions are in play.
- Objecting when you should change the return, or vice versa.
How we can help
We do not file Canadian returns or deal with the CRA. Your Canadian CPA or tax lawyer handles the NOA, NOR, objection and any relief request. From our Aurora, Illinois area base we handle the U.S. side: aligning your US return, foreign tax credits and information returns with the Canadian result, and coordinating so your Canadian CPA and our firm file consistent numbers. We cannot predict any CRA outcome. See cross-border tax and our guide to amended returns by country. Browse the notices hub for every guide in this series.
Frequently asked questions
What is the difference between an NOA and an NOR?
An NOA shows the first assessment of your return. An NOR is issued only when the CRA changes an assessed return.
Where do I find my notice of assessment?
Sign in to your CRA account, open the Individual account, and select Tax returns or Mail. The CRA says authorized representatives can find it in their representative account.
How long does a change request take?
The CRA lists two weeks for online requests, 19 weeks for mailed T1-ADJ requests and up to 35 weeks for years beyond the normal three-year period.
Can the CRA reassess a return that is more than three years old?
Yes, in listed cases such as misrepresentation attributable to neglect, carelessness, wilful default or fraud, or certain non-arm's length non-resident transactions.
Does an NOA mean the CRA accepted my return?
No. An NOA is a processing result. The return can still be reviewed or audited later within the reassessment period.
Official sources
- CRA: Notice of assessment, understand your NOA
- CRA: Notices of assessment, NOA or NOR
- CRA: Changing a tax return
- CRA: Resolving your dispute, objection rights under the Income Tax Act (P148)
- CRA: Responding to us
- Justice Laws: Income Tax Act, section 152
This page summarizes public guidance in plain language. If anything here differs from the official source, the official source controls.
General information only. It is not tax, legal, accounting or immigration advice for your situation, and rules change; confirm the current rules with the official source or a licensed professional in the relevant country.