Paying Off Faster
When to Prepay the Mortgage vs Invest
Prepay mortgage vs invest: compare after-tax returns, mortgage rates, prepayment penalties, and tax-advantaged accounts to decide where extra cash goes.
Deciding whether to prepay mortgage vs invest comes down to one comparison: the guaranteed, tax-free return you earn by shrinking your mortgage balance against the after-tax return you could earn by investing the same money. If your mortgage rate is higher than what you can realistically earn after tax and after risk, prepaying usually comes out ahead. If your expected investment return is higher and you can ride out market swings, investing may win.
Both paths assume you already qualify for your mortgage under the federal mortgage stress test, which lenders apply using the higher of your contract rate plus two percentage points or the published qualifying-rate floor. Confirm the current floor with OSFI or your lender, and note that the same rules return if you refinance or move later.
Start With the Guaranteed Return on a Prepayment
A prepayment is one of the few investments with a known payoff. Every extra dollar you put against the principal reduces the balance your lender charges interest on, and that saving compounds for the rest of your amortization. Take your own contract rate and treat it as the return you lock in by prepaying. The higher that rate is, the harder it becomes for a taxable investment to beat it.
Prepaying also shortens your amortization, which means fewer years of payments and less total interest. You can model the effect with our mortgage prepayment calculator, then compare approaches in lump-sum prepayment vs higher monthly payments.
Prepayment Privileges Set the Rules
Most closed Canadian mortgages include annual prepayment privileges, usually a percentage of the original principal plus an option to raise your regular payment. What you can prepay without a penalty depends entirely on your mortgage contract, so read it before you move money. Our guide to mortgage prepayment privileges covers the common structures.
Penalties and the interest rate differential
Prepay more than your privileges allow on a closed mortgage and you may owe a prepayment penalty. On a fixed-rate mortgage, that charge is often the greater of three months of interest or the interest rate differential (IRD), a figure that can grow when rates have fallen since you signed. Variable-rate mortgages typically use three months of interest instead. Read interest rate differential (IRD), explained before you break or exceed your terms.
Where Investing Can Beat Prepaying
Investing looks better when your mortgage rate is low relative to realistic market returns, and better still when you hold those investments in a registered account. A TFSA shelters growth and withdrawals from tax. An RRSP gives you a deduction now, though withdrawals are taxed later. The First Home Savings Account (FHSA) combines a deduction with tax-free withdrawals when you buy a qualifying first home.
Tax treatment usually decides a close call. Interest from a savings account or GIC held outside a registered account is taxed at your marginal rate, while capital gains and eligible Canadian dividends are taxed more gently. Shelter the returns and the comparison tilts toward investing.
Risk is the other half of the equation. A prepayment return is certain. Market returns are not, and a poor stretch early in your horizon can leave you behind even if long-run averages look attractive. If a market drop would force you to sell, prepaying is the safer path.
When Prepaying Wins
- Your mortgage rate is higher than a realistic after-tax return on your investments.
- You value certainty and dislike market risk.
- You are within sight of retirement and want the mortgage gone. See planning to be mortgage-free in retirement.
- You want lower required payments at renewal, which improves monthly cash flow.
- Your income may drop or become variable, and you would rather carry less fixed debt.
When Investing Wins
- Your mortgage rate is low relative to expected returns over a long horizon.
- You have unused TFSA, RRSP, or FHSA room that shelters the returns.
- You can leave the money invested through a downturn.
- You need liquidity. Home equity is not cash, and tapping it usually means a refinance or a home equity line of credit with its own costs.
A Simple Decision Framework
| Factor | Prepay the mortgage | Invest the extra cash |
|---|---|---|
| Return | Set by your mortgage rate; guaranteed | Uncertain; depends on markets and time horizon |
| Tax | Effectively a tax-free saving | Taxed outside registered accounts; sheltered inside a TFSA, RRSP, or FHSA |
| Liquidity | None; the money is locked in the home | High, especially inside registered accounts |
| Risk | None | Market risk; can be reduced with GICs or bonds |
| Best when | Mortgage rate exceeds a realistic after-tax return | Expected after-tax return exceeds the mortgage rate and you can wait out volatility |
If the two options still look close, split the difference. Prepay up to your annual privilege limit and invest the remainder. You reduce interest, keep some liquidity, and avoid the penalty that comes with exceeding your prepayment terms.
Before You Prepay, Check These Items
- An emergency fund covering several months of expenses.
- High-interest debt such as credit cards or car loans cleared first, since those rates usually dwarf any mortgage return.
- Registered contribution room reviewed so you are not giving up sheltered growth you will never get back.
- Your annual prepayment room and any penalty confirmed with your lender in writing.
- Renewal or refinance timing checked, because switching lenders while carrying a large prepayment can complicate the file.
One more practical point: shrinking your mortgage balance does not automatically change what you can borrow later. Lenders still test your GDS and TDS ratios against income and debts, and they apply OSFI Guideline B-20 and the stress test to new mortgage applications. A smaller balance can help your ratios, but it is not a promise of approval for more credit.
For a deeper look at the trade-off, read paying down the mortgage vs investing.
Frequently asked questions
Is it better to prepay my mortgage or invest?
It depends on the numbers. Prepaying gives you a guaranteed return equal to your mortgage rate with no tax and no market risk. Investing can beat that inside a TFSA, RRSP, or FHSA if your expected after-tax return is higher and you can hold through downturns. Compare your contract rate to a realistic return, then decide.
What investment return do I need to beat prepaying my mortgage?
At minimum, you need to match your mortgage rate. Outside a registered account, you need more than that because investment income is taxed at your marginal rate, so the gap widens as your income rises. Inside a TFSA or FHSA, the return is sheltered, so matching the mortgage rate is closer to break-even. Confirm your own tax situation with a qualified professional.
Can I do both, prepay my mortgage and invest?
Yes, and many homeowners do exactly that. Prepay up to your annual prepayment privilege limit so you avoid any penalty, then direct the remaining extra cash into registered investments. You cut interest, keep some liquidity, and stop one decision from having to carry all the weight. Revisit the split each year as rates and income change.
Does prepaying my mortgage hurt my ability to borrow later?
Paying down the balance reduces your debt and can improve your GDS and TDS ratios, which helps when you apply for new credit. It does not guarantee approval. Lenders still apply OSFI Guideline B-20 and the federal stress test to new mortgage applications, and they review income stability and credit history alongside your balances.