Stop guessing: The mortgage-vs-RRSP choice that could make or break your retirement

Now, the urge to become debt-free is strong — really strong. It feels responsible, safe, and immediately satisfying to pay off debt, particularly large debt such as a mortgage on a house. But what if the rush to pay off low-interest debt is quietly undermining your long-term retirement security? While there is no one right answer, tax expert Jamie Golombek argues that paying down debt actually puts your retirement at risk. In his report, Mortgages or Margaritas: Is paying down debt putting your retirement at risk? (1) he suggests that the urge to pay down debt rather than contribute to a tax-efficient savings vehicle, such as a registered retirement savings plan (RRSP), is more about appeasing emotions than making smart money decisions (2).

The emotional pull of debt freedom

In this report, Golombek surveyed Canadians to help understand what drove them to prioritize debt repayment over saving for retirement. The survey data revealed just strong the emotional pull is for Canadians to become debt-free. Among Canadians asked what they'd do if they had extra funds to spare, 72% of those aged 35 to 54 picked “pay down debt” over “add to an RRSP” (3). A further 56% confessed that the main reason was a simple desire for “the financial freedom of being debt-free.”

As Golombek points out: There’s nothing wrong with that desire — it’s human, understandable — but it highlights a gap between what feels safe and what might mathematically build retirement security (4).

The mathematical case: Investing often wins

To illustrate, let's assume you have $2,500 of extra pre‐tax earnings each year. You could either apply that toward extra mortgage payments, assuming a 4% mortgage rate, or invest in your RRSP or Tax Free Savings Account (TFSA). For simplicity, we'll assume the RRSP investment earns a 6% annualized investment return over 30 years.

If your marginal tax rate stays the same in retirement

If your marginal tax rate, today, was 30% and the early withdrawal rate is the same, then investing would put you almost $45,000 ahead as the decision to pay down debt, according to Golombek's calculations (5).

If your marginal tax rate drops in retirement

If you expect your tax rate to drop in retirement — going from 30% to 20% — the RRSP strategy improves your investment portfolio, boosting it from $ 146,700 to about $167,600 (6). As Golombek explains: if your expected investment return (after tax) exceeds the interest rate on your debt, investing may give you more in the long run.

When paying debt first still makes sense

This isn’t to say you should always invest and never attack debt. If you’re carrying high-interest debt, such as a credit card balance, or lines of credit at 20% or more interest, then paying this debt off first is almost always the best option.

Golombek identifies another reason why tackling debt first makes sense: if you’re very leveraged and wouldn’t weather a rate increase or economic shock, then reducing risk via debt repayment is prudent.

The competing goals of a homeowner/saver

For a mid-career homeowner who has a mortgage and still unsure whether to tackle debt or invest in your RRSP savings, the critical questions to answer include:

1. What is my mortgage interest rate? Is your mortgage rate higher than 5%?
YES→ Begin leaning toward paying down the mortgage, unless you expect exceptionally high RRSP returns and have a long time horizon.
NO → Rates below 5% often favour RRSP investing, especially with tax benefits and compounding.

2. What return can I reasonably expect from investing in my RRSP (net of tax)? Estimate expected long-term investment return (e.g., 4% to 6% real return for a balanced/growth portfolio), then compare that to your mortgage rate. Is your expected RRSP return (after tax) higher than your mortgage rate by at least 1% to 2%?
YES → Advantage RRSP → continue to next question.
NO → Advantage debt repayment → continue anyway for confirmation.

3. What is my time horizon until retirement? More than 15 years to retirement?
YES → RRSP investing becomes more attractive because compounding has time to work.
NO → Mortgage repayment becomes more attractive, especially if nearing retirement and wanting a lower cost base.

4. What is my tax rate now, and what do I expect it to be in retirement? RRSPs are most powerful when your tax bracket today is higher than your expected tax bracket later (say, in retirement). Is your tax rate now significantly higher than what you expect in retirement (at least one bracket difference)?
YES → RRSP advantage. RRSP contributions defer tax at a high rate and withdrawals will be taxed at a lower rate.
NO → Debt repayment advantage. The RRSP tax deferral is less impactful.

5. What is my comfort level with investment risk and debt levels? Do you feel stressed carrying debt or prefer guaranteed returns?
YES → Pay down mortgage.
NO → RRSP investing is reasonable.

6. Do you have a long investment horizon and can tolerate market volatility?
YES → RRSP investing becomes more favourable.
NO → Mortgage repayment provides a risk-free, “guaranteed” return equal to your interest rate.

Focus on RRSP investing

If you answered "Yes" to most of the following: