Should You Pay Off Your Mortgage Early?
Should you pay off your mortgage early, or invest the extra instead? The honest answer is mostly arithmetic, with a real, non-financial exception.
Of all the debt-or-invest questions, this is the one where people most often ignore the arithmetic entirely — because a mortgage is tied to the house you live in, and that makes the decision feel more emotional than a car loan or a credit card ever does. Whether you should pay off your mortgage early is still, underneath the emotion, mostly a rate comparison.
The rate comparison, stated plainly
Paying off any debt early earns you a guaranteed, risk-free return equal to that debt's interest rate. A mortgage is no different in principle — the difference is that mortgage rates are usually the lowest rate most people will ever borrow at.
A 4% mortgage competes against a stock market that has historically returned something like 7% a year on average, before inflation, with real risk attached. On a pure expected-value basis, money sent toward extra mortgage payments at 4% is money not earning the higher, if less certain, return available elsewhere.
| Extra $300/month for 20 years | Outcome |
|---|---|
| Toward a 4% mortgage | Guaranteed: saves roughly $43,000 in interest, pays off years sooner |
| Toward investments at 7% | Expected: grows to roughly $156,000, with real risk of a worse or better outcome |
One number is certain and smaller. The other is larger and depends on the market cooperating for two decades.
At a low rate, the expected-value case for investing instead is strong. It stops being strong once the mortgage rate climbs — above roughly 6-7%, the guaranteed return from paying it down starts to rival or beat the market's long-run average, without the risk.
Where the arithmetic gets more complicated
Mortgage interest may be tax-deductible, depending on where you live and whether you itemise. Where it is, the effective rate you're comparing against investing is lower than the stated rate — a 4% mortgage with a meaningful deduction might behave more like 3% in practice.
Investment returns are taxed too, unless held in a tax-advantaged account, which narrows the gap in the other direction. Compare after-tax numbers on both sides, not the headline mortgage rate against the headline market return.
PMI changes the math if you have it. If private mortgage insurance is still being charged because your equity is under 20%, extra payments that clear that threshold earn you an immediate return equal to whatever PMI is costing you monthly — often a better guaranteed return than paying down principal further does after PMI drops off.
Should you pay off your mortgage early anyway?
The arithmetic favours investing at today's typical mortgage rates, and plenty of people pay extra on their mortgage anyway — for reasons that are real even though they're not purely financial.
A paid-off house is a fixed cost that disappears. For someone approaching retirement, eliminating the largest monthly obligation reduces how much income they need to generate for the rest of their life. That has a value beyond the raw rate comparison — it's a form of risk reduction, not just a return.
Certainty has a price people are willing to pay. A guaranteed outcome, even a smaller one, is worth more to some people than a larger expected outcome with real variance attached. That's a legitimate preference, not a mistake — as long as it's made with the actual numbers in view rather than instead of them.
It removes a source of stress some people genuinely carry. If a mortgage balance keeps you up at night regardless of how the numbers pencil out, clearing it "early" at a modest cost to expected returns can be a reasonable trade for peace of mind — see the honest caveat in pay off debt or save first about psychology versus optimisation.
What should come before extra mortgage payments, regardless of the rate
Two things jump the queue ahead of extra mortgage payments in almost every circumstance:
- A real emergency fund. A house is illiquid — you can't sell a kitchen to cover three months of a job search. Extra equity doesn't help you in a cash crunch the way savings do.
- The full employer retirement match, if one exists. An instant 50-100% return beats any mortgage rate under discussion, without exception.
Only after both of those are in place does the mortgage-versus-investing comparison become the live decision.
A reasonable way to decide
If your mortgage rate is above 6-7%, extra payments are close to a guaranteed win and a defensible default.
If it's below 4-5%, the expected-value case favours investing the difference, particularly in a tax-advantaged account — but paying extra isn't a mistake if the certainty is worth more to you than the expected gap.
In between, split it: direct half of any extra toward the mortgage and half toward investing, and avoid having to make the choice entirely.
Whichever you choose, make it a decision rather than a default. The amount involved, compounded over the decades a mortgage runs, is large enough to deserve having actually been decided once.
This article is general educational information, not personalised financial advice. See our disclaimer.