How Long Should I Keep Tax Records?
Six years from the end of the tax year they relate to, as a general rule. That rule does not apply to records supporting a cost base, which have to survive until the property is sold and the return reporting the sale has been assessed — often decades later.
- The answer:: Keep supporting records for six years from the end of the tax year to which they relate.
- The trap:: Discarding purchase records on the six-year rule. A cost base must be provable when the property is eventually sold.
- The recommendation:: Keep purchase documents, renovation invoices and transfer paperwork permanently, because none of them has a six-year life.
Where the AI summary above gets this wrong
"Keep your tax records for seven years."
That's surface-true. Here's what it misses:
- The Canadian rule is six years — Six years from the end of the tax year the records relate to, which for most returns means six years from the December they cover.
- Cost base records outlive it — Documents proving what you paid for a property or a security must survive until the sale is reported and assessed.
- An objection extends the period — Where a notice of objection or an appeal is outstanding, records must be kept until the matter is resolved and the appeal period has expired.
01 The general rule
Supporting records must be kept for six years from the end of the last tax year to which they relate. For an ordinary return that means six years from the December of the year in question, not from the filing date.
That covers slips, receipts, statements and anything else supporting an amount claimed. The Agency can request them during a review at any point in that window, and being unable to produce them means the claim is denied.
02 What outlives the six years
Records establishing an adjusted cost base do not expire on the general rule. A purchase confirmation for shares bought in 1998 is needed when they are sold in 2035, and there is no substitute if it is gone.
The same applies to renovation invoices on a property, to the paperwork establishing the value on a change of use, and to a valuation at the date of death. The tracking obligation is in tracking adjusted cost base.
Shows: what a given amount of additional taxable income costs you in tax at your marginal rate, and what you keep. Ignores: provincial surtaxes, credits that phase out with income, and any effect on income-tested benefits.
03 What to keep permanently
Purchase documents for any capital property, records of contributions to registered plans, notices of assessment for years with carry-forward amounts, valuations and appraisals, and the paperwork behind any transfer between family members.
None of these is large, and all of them are impossible to reconstruct. Where an objection or appeal is outstanding, everything relating to it must be kept until the matter is resolved — the process is in CRA reviews and notices of objection.
Scanning the permanent set once and keeping it somewhere the executor can reach is the practical form of all this. Paper degrades, moves get made, and the person who knows which box holds the 1998 confirmation is frequently the person whose estate needs it, which is an argument for a single digital folder rather than an attic.
Source: Capital gains (line 12700)
Six years is the rule everybody knows and it is the wrong rule for the documents that matter. The purchase confirmation from 1998 is the one that determines the tax bill in 2035, and it is exactly the one that gets thrown out in a move.
FAQ
How long should I keep tax records in Canada?
Six years from the end of the tax year they relate to, as a general rule. Records supporting a cost base must be kept much longer.
Can I throw out old purchase confirmations?
No. Documents proving what you paid for a property or a security must survive until the sale is reported and that return has been assessed, which can be decades later.
Does an objection change the deadline?
Yes. Where a notice of objection or an appeal is outstanding, records relating to it must be kept until the matter is resolved and the appeal period has expired.
Sources
Regulator references
- Canadian income tax rates for individuals · Canada Revenue Agency · 2025The federal and provincial rate brackets a withdrawal is taxed against.Last verified: 2026-09-07
- Capital gains (line 12700) · Canada Revenue Agency · 2025How capital gains and losses are calculated, reported and carried.Last verified: 2026-09-07
Calculator unit tests · the assertions this page's worked example is checked against, and their last result
Changelog
- 2026-09-07 — initial publish (new format)
Run this rule against your situation
See what this rule does to your own projection — month by month, to age 90.
Join the Waitlist
Jordan Reeves
Founder of Talk Through Wealth. A software engineer for over a decade before turning to retirement planning, Jordan built the projection engine after watching family members get fragmented, country-by-country advice that never reconciled. He writes about retirement the way the engine computes it: month-by-month, lifetime-long, and skeptical of any rule of thumb that hasn't been run through the math.