15-year vs 30-year mortgage: which should you choose?
The same loan over a shorter term changes three things at once: your monthly payment, the total interest you pay, and how much flexibility you keep. Here’s how to weigh them — and a hybrid that gives you most of both.
The core trade-off
A 15-year mortgage and a 30-year mortgage are the same idea at two speeds:
- 15-year: a much higher monthly payment, but dramatically less total interest, faster equity, and usually a lower interest rate.
- 30-year: a lower, more manageable payment that frees up cash flow — at the cost of paying interest for twice as long, so far more interest overall.
Run both side by side in our mortgage calculator to see the exact numbers for your loan amount and rate.
Why the 15-year saves so much interest
Two forces compound. First, lenders typically price 15-year loans at a lower rate. Second — and bigger — you’re borrowing for half as long, so interest has far less time to accrue on the balance. Because mortgage interest is front-loaded (early payments are mostly interest), shortening the term cuts into the most interest-heavy years. The result is often less than half the lifetime interest of a 30-year loan.
The case for the 30-year — even if you can afford the 15
A lower required payment is not just for people who can’t afford more. It’s optionality: in a layoff, a medical event, or a great investment opportunity, the 30-year’s smaller obligation is a cushion the 15-year doesn’t give you. There’s also an opportunity-cost argument — if your expected long-term investment return is higher than your mortgage rate, investing the payment difference could outperform paying the loan down faster (though that’s never guaranteed, and debt-free certainty has real psychological value).
The hybrid most people overlook
You can capture most of the 15-year’s savings without locking yourself in: take the 30-year loan and make extra principal payments on the schedule of a 15-year. You shorten the term and slash interest — but if money gets tight, you can fall back to the lower required payment. You keep the flexibility and most of the savings. Our mortgage calculator has an extra-payment field that shows exactly how many years and how much interest a given monthly extra removes.
A quick way to decide
Ask three questions: Can I comfortably afford the 15-year payment and still fund retirement and an emergency buffer? How stable is my income? Would I actually invest the difference, or just spend it? If the 15-year payment crowds out retirement saving or a cash cushion, the 30-year (with optional extra payments) is usually the more resilient choice.
Frequently asked questions
- Is a 15-year or 30-year mortgage better?
- Neither universally. The 15-year costs far less interest and builds equity faster but has a much higher payment; the 30-year is lower and more flexible but costs more interest. It depends on your cash flow, job stability, and what else you’d do with the money.
- Why does a 15-year save so much interest?
- It usually carries a lower rate, and you borrow for half as long, so interest has far less time to accrue — often less than half the total interest of a 30-year.
- Can I get 15-year benefits with a 30-year loan?
- Largely yes — take the 30-year and make extra principal payments to mimic a 15-year payoff, while keeping the option to drop back to the lower payment if needed.