The Smith Manoeuvre, Explained

The Smith Manoeuvre (also spelled Smith Maneuver) is a Canadian strategy for slowly converting the debt on your home — which isn't tax-deductible — into investment debt, whose interest generally is. You don't borrow more all at once; you convert the character of debt you're already paying down, one mortgage payment at a time.

It's named after Fraser Smith, who set it out in his book The Smith Manoeuvre. The idea is elegant, but it leans on leverage and tax rules that don't forgive mistakes, so it's worth understanding the mechanics before you look at any projection.

The one-sentence version

Every time you make a mortgage payment, the principal portion frees up a little home equity — so you re-borrow that amount through a linked line of credit and invest it, turning a slice of non-deductible mortgage debt into (potentially) tax-deductible investment debt.

Why this is a Canadian strategy

In Canada, the interest on the mortgage for your own home is not tax-deductible. But under long-standing Canadian tax principles, interest on money you borrow to earn income from an investment generally is deductible (more on the conditions in Is investment loan interest tax-deductible in Canada?).

That gap is the whole opportunity. Homeowners in the United States can often deduct mortgage interest directly, so they have no reason to do this. Canadians can't — so the Smith Manoeuvre exists to manufacture deductible interest out of a mortgage that would otherwise give you none.

How it works, step by step

It needs a specific product: a readvanceable mortgage — a mortgage bundled with a home-equity line of credit (HELOC) whose limit grows automatically as you pay the mortgage down.

1. You make your regular mortgage payment. Part of it is interest; part pays down principal.
2. The principal you just paid becomes available credit on the linked line of credit.
3. You re-borrow that amount and invest it in something held to earn income (say, a portfolio of dividend-paying investments).
4. The interest on that investment loan may be tax-deductible, which can generate a tax refund or reduce tax owing.
5. You put the tax savings (and any investment income) back against the mortgage, paying it off faster — which frees up more credit to re-borrow, and the loop continues.

Over years, your non-deductible mortgage shrinks while a deductible investment loan grows to replace it. When the mortgage is gone, you're left holding an investment portfolio and a loan whose interest is (in principle) deductible — instead of a paid-off house and nothing invested.

What makes it powerful — and what makes it risky

The appeal is that it does three things at once: it gets you invested earlier, it converts dead mortgage interest into deductible interest, and it can shorten your mortgage. But every one of those levers cuts both ways:

• It's leverage. You're investing with borrowed money, so a market downturn hits an amplified balance. Leverage multiplies losses exactly as much as gains — see Understanding leveraged investing.
• Rates matter. The line of credit is usually variable. If borrowing costs rise faster than your investments return, the maths turns against you.
• The deduction isn't automatic. Interest is only deductible when the borrowed money is genuinely used to earn income, and the paper trail has to hold up. Careless mixing of funds can jeopardise it.
• It rewards discipline and punishes the opposite. The strategy assumes you reinvest, keep records, and don't spend the re-borrowed money. It's a multi-decade commitment.

None of this makes it good or bad — it makes it situational. Whether it's sensible depends on your income, your marginal tax rate, your risk tolerance, your mortgage, and your temperament.

Seeing the trade-offs before you commit

The hard part isn't the concept; it's that every piece interacts — your province's tax brackets, your mortgage's amortization schedule, and years of uncertain market returns, all at once. Small differences in assumptions compound over 20 or 30 years.

That's what our Leverage Strategy Analyser is designed to make visible: it models the Smith Manoeuvre against simpler approaches and an unleveraged baseline, across a range of simulated market paths and your actual tax situation, so you can see the spread of outcomes rather than a single hopeful number.

Before you act

The Smith Manoeuvre combines a borrowing strategy with a tax strategy, and both depend on details specific to you and on current Canada Revenue Agency rules (this article reflects general principles as of 2026, not a ruling on your situation). Talk it through with a qualified financial advisor and a tax professional before setting anything up — the interest-deductibility piece in particular is easy to get wrong in ways that are expensive to unwind.