The Smith Manoeuvre, explained honestly
The most Canadian strategy in personal finance: since our mortgage interest isn't deductible, convert the mortgage into debt that is. The mechanics are legal and elegant; the risks are leverage wearing a tax costume. Here's both halves, on the CRA's actual wording.
The short answer
- The ideaRe-borrow each mortgage payment's principal to invest — via a readvanceable mortgage
- The prizeInvestment-loan interest is deductible (CRA line 22100 / Folio S3-F6-C1)
- The trapCapital-gains-only investments don't qualify — CRA's own exclusion
- The truthIt's decades of leverage — right for a narrow, high-bracket, iron-stomached few
The machinery, one cycle at a time
Start with a A mortgage combined with a HELOC where the credit limit grows automatically as the mortgage principal is paid down — FCAC: 'Your available credit increases as you pay down your mortgage principal.' The big banks all sell one under different brand names. . Each monthly payment retires some principal; the HELOC limit rises by the same amount; you draw that amount and buy income-producing investments — then repeat, every payment, for the life of the mortgage. Nothing about your total debt changes month to month: non-deductible mortgage dollars are being swapped one-for-one into deductible investment-loan dollars. The refund the deduction generates is typically aimed back at the mortgage as a prepayment, which frees more credit, which accelerates the conversion — the "accelerator" that makes the spreadsheets sing. At the end: no mortgage, a portfolio bought steadily across decades, and an investment loan whose interest the CRA has been subsidizing at your marginal rate.
The tax footing — and where people slip
The deduction isn't a Smith-specific blessing; it's the ordinary CRA Folio S3-F6-C1, applying paragraph 20(1)(c): interest is deductible on 'borrowed money used for the purpose of earning income from a business or property' — and 'the use of the money must be established.' Purpose and traceability are everything. every investment loan answers to. Three places implementations die at audit. Tracing: the borrowed money's path must be provable — dedicated accounts, no commingling; one grocery run from the HELOC can contaminate the line's deductibility. The capital-gains exclusion: CRA's line 22100 page says interest isn't claimable when the investment can only ever produce capital gains — which rules out the non-distributing fund structures (swap-based products, corporate-class) that tax-sensitive investors otherwise love, and is why conventional dividend payers are the canonical vehicle. Registered accounts: borrowed money into a TFSA or RRSP earns no deduction — the strategy lives exclusively in taxable investing, with everything that implies for the location math.
The honest accounting of risk
Strip the tax paint and this is a decades-long leveraged equity position financed at a floating rate — currently prime-plus, ~5.5–6% posted, repricing with every Bank of Canada move. The deduction softens that cost (a 5.95% line costs ~3.5% after tax at a 40% bracket) but doesn't change the structure: in a 2008 or 2022, the portfolio falls while the debt holds firm, and the strategy's success depends on doing nothing — or buying more — at the exact moment leverage makes doing nothing hardest. The behavioural record, not the arithmetic, is where Smith Manoeuvres die. That's also why the fit narrows so sharply with age: the pre-retirement decade argues for removing fixed obligations against variable portfolios, and this strategy manufactures one. For the high-bracket forty-year-old with bulletproof income and a proven stomach, it's a legitimate, powerful tool. For everyone else, the boring sequence — mortgage, TFSA, savings rate — wins by being finishable.
Frequently asked questions
What is the Smith Manoeuvre?
A strategy that gradually converts non-deductible mortgage debt into tax-deductible investment debt. The engine is a readvanceable mortgage — FCAC’s definition: a HELOC combined with a mortgage where “your available credit increases as you pay down your mortgage principal.” Each regular payment frees credit; you immediately re-borrow it to buy income-producing investments. The mortgage shrinks, an investment loan grows in its place, and the loan’s interest is deductible because — per the CRA’s purpose test — it was borrowed to earn investment income. Over a full amortization, the house ends up paid AND a leveraged portfolio exists, financed by interest the taxman subsidized.
Is the Smith Manoeuvre legal — what does the CRA actually allow?
The structure rests on ordinary, settled tax law, not a loophole: CRA’s line 22100 permits deducting “most interest you paid on money you borrowed and used to try to earn investment income, such as interest and dividends,” and Income Tax Folio S3-F6-C1 frames the test — borrowed money must be used “for the purpose of earning income from a business or property,” and “the use of the money must be established.” Legal, yes; casual, no: that tracing requirement means clean separation of borrowed funds (a dedicated account, no commingling with personal spending), because one blended withdrawal can poison the deductibility of the whole line.
What’s the capital-gains trap?
The detail that disqualifies the most popular investments: CRA’s own page states the interest is not claimable “if the only earnings your investment can produce are capital gains.” Growth stocks that pay nothing, and notably swap-based or corporate-class funds engineered to never distribute, can fail the income-earning purpose test. Conventional dividend payers and dividend-paying ETFs are the standard implementation for exactly this reason — and it’s also why the borrowed money can never flow into a TFSA or RRSP (no deductible purpose inside registered accounts).
What are the real risks?
It’s leverage, with leverage’s full personality. Both directions amplify: a 30% market drop on a borrowed portfolio is a real loss against a debt that didn’t shrink. The rate floats: HELOC portions price at prime-plus (5.45–5.95% posted at our last check) and reprice with every BoC move, while the dividends funding the interest don’t. The discipline is forever: decades of monthly re-borrowing, clean records, and not panic-selling in 2008-style years — the strategy’s academic math assumes a robot executes it. And the deduction’s value scales with your bracket, so it flatters high earners and underwhelms modest ones. Anyone whose payoff-vs-invest answer wasn’t already “invest, comfortably” has no business adding borrowed money to the question.
Who actually fits this strategy?
A narrow profile, honestly drawn: high marginal rate (the deduction is the engine — worth roughly twice as much at 45% as at 25%), secure income and fat cash-flow margin (the HELOC payment must survive job loss and rate spikes), long runway (a decade-plus for the conversion to matter), iron behavioural record in past bear markets, and ideally an accountant who’s filed these before. The anti-profile is equally clear: approaching retirement (this is the opposite of the de-risking the pre-retirement decade calls for), variable income, or any history of selling in drawdowns. Most households reading this are better served by the boring version: pay the mortgage, fill the TFSA, sleep.
Educational reference, not tax or investment advice — this page describes a leveraged strategy without recommending it. CRA wording per line 22100 and Income Tax Folio S3-F6-C1 (verified June 11, 2026); readvanceable definition per FCAC; HELOC pricing as posted at verification. Deductibility is fact-specific and tracing-dependent — engage an accountant experienced with this exact structure before borrowing a dollar.