The 21-Year Rule for Family Trusts in Canada
A family trust feels timeless — a structure that holds wealth quietly across generations. The Income Tax Act disagrees. Buried in the trust rules is a clock that starts the day the trust is created and goes off every 21 years, deeming the trust to have sold everything it owns and handing it a capital gains bill on assets it never actually sold. Trustees who do not know the clock exists discover it the expensive way; trustees who do plan around it years in advance. This is one rule where ignorance is genuinely costly.
This guide explains the 21-year rule, which trusts it hits, and how it is managed. It is general information, not advice; trust tax planning is specialist work.
What the rule does
Under the Income Tax Act, most trusts are deemed to dispose of their capital property at fair market value every 21 years, and to immediately reacquire it at that value.[1] The trust pays tax on the accrued capital gain — currently 50% of the gain included in income[3] — even though it has sold nothing. It is a deemed realization, designed to force a periodic tax reckoning inside the trust.
Why it exists
The logic is anti-deferral. An individual faces capital gains tax on their assets at death; without the 21-year rule, those same assets could sit inside a trust appreciating for generations and never trigger the tax. The rule prevents trusts from becoming permanent tax-deferral vehicles by imposing a deemed disposition on a regular cycle.
Which trusts are caught — and which are timed differently
Most family (inter vivos) trusts and many testamentary trusts are subject to the 21-year rule. The notable exceptions are not exempt so much as timed to a death:
- An alter ego or self-benefit trust is first deemed to dispose of its capital property on the settlor's death.
- A spousal or joint partner trust is first deemed to dispose on the death of the second spouse.
Those trusts still face a deemed disposition — just triggered by a death rather than the 21-year anniversary. See alter ego trusts and joint and spousal trusts.
How trustees plan around it
The standard strategy is to distribute the trust's capital property to its beneficiaries before the 21-year date. A tax-deferred rollout to Canadian-resident beneficiaries can transfer the assets out of the trust at the trust's cost base, so the accrued gain moves with the asset and is deferred until the beneficiary eventually sells — rather than being taxed in the trust at the top rate. The alternative is simply to let the trust pay the tax. Either way, the decision should be made well before the anniversary, with a tax advisor, because the rollout takes planning and a missed date is an unplanned bill.
The filing
A trust generally files a T3 return each year, reports income, and issues slips to beneficiaries, with trusts taxed at the top marginal rate on income they retain.[2] Recent federal rules also require most trusts to disclose their settlors, trustees, and beneficiaries. The 21-year deemed disposition is reported through this filing when it occurs.
What we focus on at It's Simple Will
The Will Creator handles wills for the great majority of Canadians, whose estates do not involve a family trust. Where a trust is part of your plan, the 21-year rule is one of several reasons it belongs with a tax advisor and lawyer — and a date worth recording the day the trust is settled. For the basics, see family trusts in Canada.
Related guides
Citations & sources
- [1]Income Tax Act, RSC 1985, c 1 (5th Supp), s 104(4) — deemed disposition by a trust — Justice Laws Website, Government of Canada
- [2]T3 Trust Guide (T4013) — Canada Revenue Agency
- [3]Prime Minister cancels proposed capital gains tax increase (March 21, 2025 — inclusion rate stays at 50%) — Prime Minister of Canada
Frequently asked questions
What is the 21-year rule?
A rule in the Income Tax Act under which most trusts are deemed to have disposed of their capital property at fair market value every 21 years, and to have immediately reacquired it at that value. The trust pays tax on the accrued capital gain even though it has not actually sold anything — a deemed realization, not a real sale.
Why does the rule exist?
To prevent indefinite tax deferral. Without it, appreciating assets could sit inside a trust for generations without ever triggering the capital gains tax that an individual owner would face at death. The 21-year deemed disposition forces a periodic reckoning so gains cannot accrue tax-free forever inside a trust.
Which trusts are affected?
Most family (inter vivos) trusts and many testamentary trusts. The main exceptions are timed to a death instead of 21 years — an alter ego or self-benefit trust is first deemed to dispose on the settlor's death, and a spousal or joint partner trust on the death of the second spouse. Those still face a reckoning, just on a different trigger.
How do trustees plan for it?
Commonly by distributing the trust's capital property to its beneficiaries before the 21-year date. A tax-deferred rollout to Canadian-resident beneficiaries can move the assets — and their accrued gains — out of the trust at cost, deferring the tax until the beneficiary later sells. The alternative is to let the trust pay the tax at the top rate.
When should we start planning?
Well before the 21-year anniversary — ideally a few years out. Rolling out assets, valuing them, and coordinating with the beneficiaries' own situations takes time, and a missed deadline means an unplanned tax bill at the trust's top marginal rate. Mark the date when the trust is created and engage a tax advisor early.
Does the trust file a tax return?
Yes. A trust generally files a T3 return every year, reports its income, and issues slips to beneficiaries. Trusts are taxed at the top marginal rate on income they retain, and recent rules require most trusts to disclose their settlors, trustees, and beneficiaries. The 21-year deemed disposition is reported through this filing.