Should you pay off a 8% mortgage or invest?
With a 8% mortgage and a 7% expected investment return, paying the mortgage down faster ends roughly $40,176 ahead after 30 years. But that's only the math on averages — paying off a mortgage is a guaranteed return and buys real peace of mind.
Why the mortgage rate decides it
Paying off a mortgage is a guaranteed return equal to the mortgage rate. Investing is an expected return with risk. So the comparison is simply 8% guaranteed vs ~7% (risky) expected:
- When the mortgage rate is well below your expected return (like 8% vs 7%), investing usually wins on average — your money compounds faster than the loan costs.
- When the mortgage rate approaches or exceeds your expected return, paying it off wins — and it's a certain win, with no market risk.
- Guaranteed vs risky matters. A paid-off house lowers your fixed costs and sequence-of-returns risk in retirement. Many people rationally choose the guaranteed return even when investing edges it out on paper.
Before you decide
A few things this comparison assumes you've already handled: capturing your full 401(k) match (an instant ~100% return that beats both), paying off any high-interest debt (credit cards dwarf a mortgage rate), and keeping an emergency fund. Money locked in home equity is hard to access without a sale or a HELOC — so don't pay down the mortgage with money you might need.
Assumptions: $450k home, 20% down, 30-yr term, an extra $12,000/yr toward principal, 7% investment return, 3% inflation, single filer. Mortgage interest is only deductible if you itemize — most people take the standard deduction, so this treats it as non-deductible. Model your own numbers in the calculator.
At this rate the math and the peace of mind point the same way
Usually the payoff-versus-invest debate pits cold arithmetic against emotional comfort. At a rate this high they stop pulling in opposite directions. A guaranteed return this large is difficult to beat anywhere safe, so choosing certainty costs little or nothing in expected terms — which lets the human factors decide without penalty.
Those factors are not soft. A paid-off home is a fixed cost that can never be missed, foreclosed on, or repriced. It lowers the income you must earn or withdraw to feel secure, which can make a job change, a sabbatical, or an earlier retirement feel possible. And there is a plain behavioral truth: many people stick with a payoff plan far more faithfully than with a disciplined investing plan, and a strategy you actually follow beats a better one you abandon.
None of this replaces the essentials — capture the employer match, clear costlier debt, and keep an emergency fund before accelerating principal. But once those are in place, a rate this high is the setting where paying it off and sleeping better are, unusually, the same decision.
Common questions
Should I pay off a 8% mortgage or invest?
On average, paying off the 8% mortgage wins by about $40,176, because that guaranteed return beats a ~7% risky one. But paying off is guaranteed and risk-free, which many people rationally prefer.
Is it worth paying off my mortgage early?
Financially it's worth it when your mortgage rate is at or above your expected after-tax investment return. Below that, investing usually builds more wealth — though a paid-off home reduces risk and fixed costs, which has real value beyond the math.
What should I do before paying extra on my mortgage?
Capture your full 401(k) match, clear high-interest debt (credit cards), and hold an emergency fund first — each of those beats extra mortgage payments. Only then does paying down a low-rate mortgage compete with investing.