Your CRA notice of assessment — line by line

A notice of assessment arrives with an unexpected number at the top. Do not panic or file it away: the notice is short and structured, and once you know each block you can check it against your return in minutes.

What a notice of assessment actually is

The notice of assessment (NOA) is the CRA’s summary of the amounts it calculated from the return you filed. A notice of reassessment (NOR) is the same document reissued after something changed — either because you asked for an adjustment or because the CRA did. Both are issued into your CRA account once the return is processed, and both are worth keeping: the notice is what banks and lenders ask for as proof of income, and it carries the figures you need for next year’s return. A notice of assessment in Canada is not a bill. It is the CRA’s statement of where your return landed.

An assessment is not the CRA’s final word. It is the agency’s first pass, made from the return you sent and the data it already holds. It can be reviewed later, and you can dispute it.

Reading it block by block

Notice details

The header shows the tax year, the date issued and the last digits of your SIN or account number. Two matter more than they look. The tax year tells you which return this is — if you filed several years at once, the CRA assesses them together and the combined result appears on the last notice. The date the notice was issued starts every dispute deadline, so write it down.

Account summary

This is the answer block, with three possible outcomes: a refund, an amount due, or nil. It can include concurrent assessments and balances carried from earlier years, the usual reason a notice shows more owing than the return you just filed.

Tax assessment summary

Here the CRA lists key line numbers and the amounts it used. Compare them line by line with your copy: a match means the line was accepted as filed; a difference means something changed, and the next section says what.

Explanation of changes

Any CRA correction is described here, usually in a short paragraph tied to a line number. Changes come from what you sent with the return or what the CRA already had, such as slips from an employer or payer. A forgotten slip is the most common cause.

RRSP and registered plan statements

A personal notice also shows your RRSP deduction limit and contribution room for the coming year and, if it applies, your Home Buyers’ Plan balance to repay. These forward-looking figures are not part of the assessment; use them to plan contributions.

What to do when the number is wrong

There is an order to this, and skipping steps costs time.

1. Compare first. Pull your filed return and match it line by line to the assessment summary. Most surprises resolve here, a missed slip, a transposed figure, a credit claimed twice.
2. If you left something out, adjust. An omission or an error on your side is an adjustment request, not a dispute. That is a different and much faster process than objecting.
3. If the CRA got it wrong, call before you object. Many disagreements are a misunderstanding that a phone call to the number on the notice clears up.
4. If it still stands, object formally. That is a notice of objection, and it is time-limited from the date on your notice.

Why a notice can take longer than usual

If your assessment has not arrived, the return may have been filed late or be under review, several returns may have been filed at once, or the CRA may have asked for more documents. A review is not an audit; it is a request for support behind a claim, covered in our guide to CRA reviews and audits.

Corporate notices are the same idea

An incorporated business gets a T2 assessment in the same shape: filed, changed, owing. The difference is the deadlines — corporate filing and payment dates are separate and not tied to the assessment date. See our guide to T2 deadlines and late-filing penalties; CRA My Business Account shows assessed balances in one place.

The bottom line

Read the account summary, then the explanation of changes, then compare the line numbers to your return. That sequence answers almost every question a notice raises. If it does not, note the date on the notice — every remedy runs from it, and get advice before the clock runs out. Handling assessments and CRA correspondence is part of our tax services.

This article is general information for Canadian business owners and is current as of July 2026. It is not tax, legal or accounting advice, and it does not create a client relationship. Tax rules change and your situation is unique, so please speak with a CPA before acting on anything here.