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Is a 15-year mortgage worth it vs. a 30-year?

The 15 charges a bigger payment and saves a fortune in interest. The 30 keeps payments manageable and leaves money you could invest. We run both.

Your numbers

Loan amount ($)

30-year rate (%)

15-year rate (% — usually 0.5–0.75 lower)

If you took the 30, return on investing the payment difference (%/yr — 0 if you'd just spend it)

The verdict

Principal and interest only — taxes and insurance are the same either way. Estimates for education only, not financial advice.

Why the interest gap is so enormous

A 30-year mortgage isn't just "the same loan, slower." Stretching the schedule means the balance stays high for longer, and interest is charged on that balance the whole time — plus 30-year rates themselves run higher than 15-year rates. Those two effects compound into a total-interest difference that routinely exceeds six figures on an ordinary loan. Run your numbers above and look at the interest line; it surprises almost everyone the first time.

The affordability rule comes first: the 15-year only makes sense if the payment fits comfortably — most guidelines suggest total housing costs under about 28% of gross income, with your emergency fund intact. A 15-year payment you can barely make is worse than a 30-year payment with breathing room, because the mortgage doesn't care that you had a bad year.

The honest case for the 30-year

Flexibility is a feature. You can pay a 30 like a 15 — send extra principal every month — and stop anytime life demands it. The reverse isn't true: a 15's payment is mandatory forever. The 30-paid-like-a-15 costs slightly more in rate but buys an escape hatch.
The invest-the-difference argument. If the payment gap genuinely gets invested at returns above your mortgage rate, the 30 can end up ahead. The calculator models this — but notice it requires discipline every single month for decades, and most people's difference quietly becomes lifestyle instead.
Other goals may outrank the house. Unmatched retirement contributions, a thin emergency fund, or high-rate debt all beat extra mortgage principal in priority order.

The honest case for the 15-year

It's a commitment device with a lower rate attached. The savings are guaranteed, automatic, and immune to willpower — no market risk, no discipline required beyond making the payment you signed up for. People who take 15-year loans actually end up mortgage-free in 15 years; people who plan to "pay extra on the 30" often don't. And owning your home outright in your fifties instead of your seventies changes what retirement looks like.

Common questions

What about a 20-year mortgage?

A legitimate middle path — rates between the two, payment between the two. Run this calculator twice using the 20-year quote in each slot to see where it lands for you.

Should I refinance my 30 into a 15?

Same math plus closing costs: compare your current loan's remaining schedule against the new 15's total cost including fees. Our car refinance page explains the term-length trap, and the identical logic applies to houses.

Does the 15-year build equity faster?

Dramatically. Early 30-year payments are mostly interest; early 15-year payments are majority principal from much sooner. If you might sell in five to seven years, the 15 leaves you with far more of the sale price.