Fixed Rate vs Variable Rate Mortgage Investments

Most people think about fixed and variable rates when they borrow, not when they lend. But every mortgage investor — direct, syndicated or through a mortgage investment corporation (MIC) — is on the other side of that choice, and the fixed rate vs variable rate mortgage investment decision decides who absorbs a change in interest rates: the borrower or the lender. This page explains the trade-off both ways, without a verdict, because the answer depends on rates nobody can forecast.

Mortgage investments are not guaranteed. Returns are targets, not promises, and principal can be lost. This is general education, not investment, tax or legal advice.

How fixed and variable rates work on a mortgage investment

A fixed-rate mortgage sets one interest rate for the whole term; a variable-rate mortgage sets the rate as a benchmark plus a spread, so it changes when the benchmark changes. On a fixed-rate loan, the lender knows its contractual income for the term. On a variable-rate loan, the lender’s income rises and falls with the benchmark, and the agreement may include a rate floor (a minimum rate) that limits how far it can fall.

Many short-term private mortgages are written at a fixed rate for a term of a year or less, often on an interest-only basis, so the variable-rate question arises mostly on longer loans and in how a portfolio reprices over time. The glossary defines terms such as spread, floor and interest-only.

Does a variable-rate mortgage investment pay more?

Not reliably. In principle, fixed and variable loans are each priced at funding to reflect the market’s expectations, and whether variable ends up paying more depends on what rates do afterwards. If the benchmark rises, the variable-rate lender earns more; if it falls, the lender earns less, down to any floor.

There is a second effect that headline comparisons miss. When rates rise, the variable-rate borrower’s payments rise too. A borrower stretched by higher payments is more likely to fall behind, so part of the extra income can be offset by higher default risk — and credit losses are where mortgage investors lose principal. Higher potential return comes with higher risk.

Worked example (illustrative): one year, $100,000, three rate paths

Assume a $100,000 interest-only mortgage investment held for 12 months. The fixed-rate loan pays 9%. The variable-rate loan pays a benchmark plus 4%, with the benchmark at 5% when funded (so 9% to start), and the benchmark moves once, by one percentage point, after six months. Assume an administration fee of 1% of principal a year and a 40% marginal tax rate, with all interest taxable as income. All figures are illustrative.

After tax, the variable outcomes range from $300 below to $300 above the fixed result. What the table cannot show is that in the “rates rise” column the borrower’s interest cost for the second half-year went up by $500, and in the “rates fall” column the fixed-rate borrower may try to refinance early, subject to the loan’s prepayment terms. The after-tax yield calculator lets you run other assumptions. Tax treatment is stated as at October 2026; confirm your own position with a Canadian tax professional.

Who carries interest rate risk in each?

On a fixed-rate loan, the lender carries the market-rate risk and the borrower carries none during the term; on a variable-rate loan, the borrower carries it and the lender’s income floats. Neither arrangement removes the risk — it only decides who holds it.

• Fixed-rate lender. If rates rise, the lender keeps earning the old, lower rate until maturity. On a long fixed term that is a real opportunity cost, and the loan would be worth less to anyone buying it. If rates fall, the lender keeps the higher rate — unless the borrower prepays.
• Variable-rate lender. Income tracks the market, so there is little opportunity cost, but the lender inherits more of the borrower’s payment stress when rates climb, and earns less when they fall.

Our guide to interest rate risk for mortgage investors covers how this plays out across a portfolio.

Why mortgage investment term length matters as much as rate type

On short terms, the fixed-versus-variable distinction narrows, because a fixed-rate loan that matures within months is repriced at the market rate on renewal or replaced by a new loan. A portfolio of short fixed-rate loans with staggered maturities therefore behaves partly like a variable-rate book: its average yield follows market rates with a lag.

Short terms bring their own risk. Every maturity is a point at which the borrower must repay or renew, and a borrower who cannot refinance falls into maturity default. Money that comes back, early or on time, must be relent at whatever rate is then available — reinvestment risk. Our guide to terms, renewals, early repayment and discharge explains each exit.

What fixed and variable mean inside a MIC

A MIC investor does not hold fixed or variable loans directly; the investor holds shares, and the distributions reflect the whole portfolio’s net income after expenses and any loan losses. Lendmax Capital MIC, for example, lends on terms of 3 to 12 months with staggered maturities and pays distributions quarterly. Distributions from any MIC can rise or fall as loans reprice, as defaults occur and as the board decides; they are not fixed even when every underlying loan is.

Under subsection 130.1(2) of the Income Tax Act, a MIC’s taxable dividends (other than capital gains dividends) are treated in the shareholder’s hands as interest, so they are taxed like the interest in the example above, as at October 2026. Our guide to where mortgage investment returns come from breaks down the components.

Fixed and variable mortgage investments compared

The table holds the borrower, property, loan-to-value and term constant; only the rate type differs.

Common mistakes

• Assuming variable pays more because rates might rise. Rates can fall, and rising rates raise default risk.
• Ignoring floors and prepayment terms. A floor changes the downside on a variable loan; prepayment terms change the upside on a fixed one.
• Treating a MIC distribution as fixed. Distributions depend on portfolio income and losses and can be reduced or suspended.
• Looking at rate type without term. On short terms, maturity and reinvestment matter more than how the rate is set.

What this means for a mortgage investor

Fixed and variable rates decide who carries interest rate risk, not whether risk exists: fixed-rate lenders give up upside when rates rise and face reinvestment risk when loans prepay, while variable-rate lenders take on income variability and more borrower payment stress. Neither reliably pays more, and short terms narrow the difference. Rate type is one feature to read alongside the seven axes on which mortgage investments vary — the borrower, the property, the loan-to-value, the security position, the term, the jurisdiction and the investment structure.