The most powerful force in Canadian investing isn't picking the right stock — it's giving your money enough time to compound. Here's exactly what that looks like in CAD.
Simple interest earns returns only on your original investment. Compound interest earns returns on your original investment plus all the returns you've already earned. Over long periods, the difference is staggering.
Imagine you invest $10,000 and earn 7% per year. In year one, you earn $700. But in year two, you earn 7% on $10,700 — that's $749. In year three, 7% on $11,449 — that's $801. Each year, the base grows, and so does the interest earned on it. This is the snowball effect that Albert Einstein reportedly called "the eighth wonder of the world."
For Canadian investors, compound interest is the core engine behind TFSA and RRSP growth. Every year you delay investing is a year of compounding you can never get back.
FV = Future Value — the total amount you'll have
PV = Present Value — your starting investment today
r = Annual return rate (e.g., 0.07 for 7%)
n = Number of years invested
For monthly contributions, the formula expands, but the principle is the same: each contribution starts earning compound returns from the day it's made, and earlier contributions earn the most.
You invest $10,000 in your TFSA and earn an average of 7% per year (a reasonable long-run estimate for an all-equity ETF portfolio). You don't touch it.
Your $10,000 investment becomes $76,123 after 30 years — without adding a single dollar more. That's 661% growth on doing nothing.
Most Canadians invest steadily over time rather than with a single lump sum. Here's what $500 per month looks like — roughly the maximum annual TFSA contribution spread monthly.
After 40 years, you've contributed $240,000 of your own money — and compounding has added nearly $958,000 on top of that.
This is the one most Canadians don't run the numbers on. The difference between a 0.20% MER (a good ETF) and a 2.20% MER (a typical Canadian mutual fund) isn't just the annual fee. Over decades, fees compound just like returns do — in the wrong direction.
| Investment Type | Annual Return Assumption | MER Drag | Net Return | 30-Year Result |
|---|---|---|---|---|
| All-equity ETF (e.g., XEQT) | ~7% gross | ~0.20% | ~6.8% | $556,000+ |
| High-fee mutual fund | ~7% gross | ~2.00% | ~5.0% | $416,129 |
The fee difference costs you over $140,000 over 30 years — on the same underlying market returns. That's money going to the fund company, not your retirement.
The average Canadian equity mutual fund charges a 2%+ MER. A comparable iShares or Vanguard ETF charges 0.20% or less. Same market. Same returns before fees. $140,000+ difference in your pocket over 30 years. This is why fee minimization is one of the highest-impact investing decisions you can make.
You don't need a spreadsheet to estimate how long it'll take your money to double. Just divide 72 by your annual return rate.
The Rule of 72 illustrates why the difference between a 4% and 7% return isn't just "a bit more." At 7%, your money doubles every 10 years — meaning someone with 30 years until retirement can expect to see it double roughly 3 times. At 4%, it only doubles twice. That's a massive difference in outcomes over a career of investing.
The 7% figure gets used a lot. Here's what's actually realistic for different Canadian investment vehicles in 2026.
| Investment Type | Example Products | Expected Annual Return | Notes |
|---|---|---|---|
| All-equity ETF | XEQT, VEQT | 7–8% long-term | Higher short-term volatility; best for 10+ year horizons |
| Balanced ETF (60/40) | XBAL, VBAL | 5.5–6.5% long-term | Smoother ride; lower highs and higher lows |
| Conservative ETF (40/60) | XCNS, VCNS | 4–5.5% long-term | More bonds; better for near-retirement horizons |
| GICs (1–5 year) | Bank GICs, credit union GICs | 3.8–4.5% (2026 rates) | Guaranteed; low risk; locked in for term |
| HISA (High-Interest Savings) | EQ Bank, Oaken, Simplii | 3–4% (2026 rates) | Fully liquid; rate fluctuates with Bank of Canada |
Note on inflation: The returns above are nominal (before inflation). If inflation averages 2.5%, a 7% nominal return is roughly 4.5% in real purchasing power. Even adjusted for inflation, long-term equity investing significantly outperforms keeping money in savings accounts.
Every compound interest illustration tells the same story — but it bears repeating with real numbers because the impact is so counterintuitive.
Ten extra years of compounding doubles your outcome — from $10,677 to $21,724. The 10-year-earlier investor contributes the same $1,000, but ends up with more than twice as much at retirement.
This is why "I'll start investing when I have more money" is such a costly delay. The money you invest at 25 does the most work — because it has the most time to compound. A $500 contribution today is worth far more than $1,000 ten years from now.
For Canadians, the practical implication is clear: max out your TFSA first (tax-free compounding), then your RRSP (tax-deferred compounding), then your non-registered account. Even small amounts — $100/month starting at 22 — grow into substantial sums by retirement.
The takeaway: Compound interest is not a complicated concept — it's just time working for you. The formula is simple, the math is straightforward, and the strategy is accessible to every Canadian. Open an account, buy a low-cost ETF, and let the compounding begin.
The math is clear. The next step is picking the right accounts and ETFs. Start here.
Beginner's Guide Best ETFs CanadaBestMutualFunds.ca provides general financial education for Canadian investors. Return projections are for illustrative purposes only — actual returns will vary. Past performance does not guarantee future results. All figures in CAD. Not a registered investment advisor.