The CRA 3-Year Rule: Income Tax and GST/HST Assessments

The CRA three-year rule usually refers to the normal income-tax reassessment period for an individual or Canadian-controlled private corporation, measured from the earlier of the original notice of assessment and any original notification that no tax was payable. After that, the year is generally statute-barred unless an exception applies — for GST/HST, the general assessment limit runs four years (see table below).

What Is the CRA 3-Year Rule? 3, 4, and 6 Years Compared

Rule	Time Limit	Applies To
Normal reassessment period	3 years	Income tax (individuals and CCPCs)
Normal reassessment period, non-CCPC corporations	4 years	Income tax (corporations other than CCPCs), from the earlier of the original notice of assessment and any original notification that no tax was payable
GST/HST net-tax assessment	Generally four years after the later of the due date and filing date	Section 298 has exceptions, including misrepresentation attributable to neglect, fraud and a valid waiver
Input Tax Credit claim window	Generally four years, with shorter periods for some registrants	GST/HST registrants (2 years for certain large businesses/financial institutions)
Record retention	6 years	GST/HST records generally, with possible longer retention
Taxpayer relief for penalties and interest	Generally subject to a 10-year limit	Specific relief provisions, tax type and timing determine eligibility
Collection of an assessed tax debt	Generally 10 years, reset by a CRA collection action	Income tax debt collection — distinct from the 10-year taxpayer-relief window above

The 3-year figure people repeat online is real — it just belongs to income tax, not sales tax. GST/HST runs on its own, longer clock.

When Does a Tax Year Become Statute-Barred?

Once the three-year normal reassessment period for an individual or CCPC — or the four-year period for other corporations — runs out, counted from the earlier of the original notice of assessment and any original notification that no tax was payable, the tax year is generally statute-barred: the CRA can no longer reopen it as of right. Several exceptions let the Minister reassess beyond that period. First, a misrepresentation attributable to neglect, carelessness or wilful default, or any fraud in filing the return, allows reassessment after the normal period, but only for matters reasonably related to that misrepresentation or fraud. Second, filing a waiver in prescribed form (Form T2029) within the normal reassessment period lets the CRA reassess that year, but only for the matters the waiver specifies; once a notice revoking the waiver is filed, the CRA has six months to reassess. The Income Tax Act also extends the period in specific situations, including three years beyond it when a required foreign-property form goes unfiled together with unreported foreign income, and up to six years beyond it where the earlier year must be reassessed to account for a loss carried back from a later year, and an assessment of that later year made after its own normal reassessment period, as a consequence of a transaction with a non-arm’s-length non-resident, reduces the loss. If an unreported disposition of real property is later reported on a prescribed form amending the return, the CRA can reassess until three years after that form is filed, but only for amounts related to that disposition; this extension does not apply to a real estate investment trust, and for a corporation or partnership the property must be capital property. The foreign-property and loss-carryback extensions run from the end of the normal reassessment period, not from the original assessment date.

Does the CRA Give You 3 Years to File a GST/HST Return?

No. A GST/HST return is due on its applicable deadline, not three years after the period. Monthly and quarterly filers generally file and pay one month after period-end; most annual filers file and pay three months after fiscal year-end. An individual annual filer with a December 31 fiscal year-end and business income for income-tax purposes generally pays by April 30 and files by June 15. Check weekend and holiday adjustments. A return may still be required for a period with no sales; use the nil option only if all fields are zero. CRA reporting deadlines.

When Can the CRA Audit or Reassess You?

For a GST/HST net-tax assessment, the general limitation is four years after the later of the return’s due date and the date filed. Section 298 permits assessment outside the normal period in specified circumstances, including a misrepresentation attributable to neglect, carelessness or wilful default, fraud, or a valid waiver. Other assessment types have their own rules. An audit is not itself an assessment; do not assume an unfiled period is automatically time-barred. Excise Tax Act section 298.

How Long Must You Keep Records? (The 6-Year Rule)

Keep GST/HST records generally for six years from the end of the year they relate to. CRA can require a longer period, and early destruction requires written permission. CRA record-retention guidance.

How to File an Overdue or Current Return

Most registrants must file electronically using one of the five methods CRA lists: My Business Account, GST/HST NETFILE, TELEFILE, Electronic Data Interchange or Internet File Transfer; charities, selected listed financial institutions and approved case-by-case exemptions have different rules. My Business Account does not require a separate access code; the standalone NETFILE form does.

Quick Answers

Can the CRA reassess a reassessment? Yes — the Minister can reassess a year, including a year already reassessed, as often as needed within the normal reassessment period counted from the earlier of the original notice of assessment and any original notification that no tax was payable. After that period ends the year is generally statute-barred, and the CRA can reassess again only under a statutory exception, such as misrepresentation, fraud, a waiver or one of the extended periods described above.

Can the CRA audit me after three years? Audit powers and assessment limits are different. The ordinary GST/HST net-tax assessment rule is generally four years from the later of the due date and filing date, with statutory exceptions; check the particular situation.

Do I have three years to file back taxes? No. File by the applicable due date. Interest and penalties depend on the return, balance owing and other conditions.

How many years of GST/HST records should I keep? Generally six years from the end of the year to which they relate. CRA may require longer retention; early destruction requires written permission.

This is general information, not legal or accounting advice. Confirm your specific filing and reassessment dates through CRA My Business Account, or with a professional, before relying on them.

Sources

Sources checked October 17, 2026.