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Waiving the Normal Reassessment Period: Why the CRA Might Ask You To

Understand what a CRA reassessment period waiver does, why the CRA requests one during an audit, and the risks and benefits of signing.

Tax6 min readTSLBy the Treadstone Law team · OntarioUpdated 2026-07
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Key takeaways
  • Under the Income Tax Act, the CRA normally has to reassess a tax year within a fixed window after your original Notice of Assessment — 3 years for individuals and Canadian-controlled…
  • Audits, especially complex ones, sometimes take longer than the time remaining before the normal reassessment period expires.
  • If the auditor genuinely needs more time to properly evaluate your position — including evidence and arguments favourable to you — a waiver can result in a better outcome than a rushed…

Partway through an audit, some Ontario taxpayers get an unexpected request: sign a waiver giving up the protection of the normal reassessment period for a specific tax year. It can feel like a trap — why would you ever agree to let the CRA take more time to reassess you? But the reasoning behind the request, and the calculation on whether to sign, is more nuanced than it first appears.

What the Waiver Actually Does

Under the Income Tax Act, the CRA normally has to reassess a tax year within a fixed window after your original Notice of Assessment — 3 years for individuals and Canadian-controlled private corporations, 4 years for other corporations and mutual fund trusts. Once that period expires, the year becomes statute-barred and generally closed to reassessment.

A waiver is a signed document that suspends this deadline for a specific tax year and specific matters described in it, giving the CRA more time to complete its review of that year without the normal reassessment period cutting the audit short. The waiver doesn't extend indefinitely or automatically — it applies to what it says, for as long as it remains in effect.

Why the CRA Asks for One

Audits, especially complex ones, sometimes take longer than the time remaining before the normal reassessment period expires. If the CRA is close to the deadline and hasn't finished its review, it faces a choice: reassess quickly based on incomplete information, or ask you to extend the deadline so the audit can be completed properly. The waiver request is usually the second option — and, from the CRA's perspective, it's often framed as being in everyone's interest, since a rushed reassessment based on partial information can be worse for you too.

The Case For Signing

The Case Against Signing

Questions to Ask Before Signing

  1. What specific tax year and issues does the waiver cover? A waiver limited to the exact matter under review is very different from one written broadly enough to reopen anything the CRA later finds.
  2. Why does the auditor need more time — and how much more? A vague request deserves a more skeptical response than one tied to a specific, identifiable gap in the audit.
  3. What happens if I decline? In many cases, declining simply means the CRA reassesses based on what it currently has, which starts the objection process on a timeline you can control — sometimes a reasonable trade-off compared to extending an open-ended audit.
  4. Have I gotten independent advice on the wording? The CRA drafts the waiver in its own interest; having a tax lawyer review or negotiate the wording protects yours.

A Practical Comparison

Sign the waiverLet the deadline pass
Audit timelineExtended for the covered issueEnds when the normal reassessment period expires
Your certaintyDelayed — outcome still pendingFaster — the year becomes statute-barred (for issues not covered by a fraud or misrepresentation exception)
CRA's informationMore complete before any reassessmentMay be forced to reassess on what it currently has
ReversibilityDifficult — formal cancellation, delayed effectN/A — no action needed

Frequently asked questions

Am I required to sign a waiver if the CRA asks?

No. Signing is voluntary. Declining doesn't stop an ongoing audit, but it does mean the CRA's ability to reassess that year is bounded by whatever time remains in the normal reassessment period.

Does signing a waiver mean I'm admitting I owe more tax?

No. A waiver is procedural — it extends the CRA's time to complete its review. It isn't an admission about the substance of the audit or an agreement to any specific reassessment amount.

Can I limit what a waiver covers before signing it?

Often, yes, with the right advice — the wording of a waiver can sometimes be negotiated to cover only the specific issue genuinely still under review, rather than the broadest language the CRA initially proposes.

If I already signed a waiver and regret it, can I cancel it?

A signed waiver generally needs to be formally revoked, and revocation typically doesn't take effect immediately — there is usually a waiting period built in. Speak with a tax lawyer about your specific waiver's terms before assuming you can simply withdraw it.

This article is general information, not legal advice. Reading it does not create a lawyer-client relationship. Ontario laws, tax rates, and government programs change, and how the law applies depends on your specific facts. For advice about your situation, speak with a licensed Ontario lawyer. Treadstone Law is licensed by the Law Society of Ontario — reach us at 1-844-900-1070 or start a file online.

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