On a $400,000 loan at 6.5%, a 15-year mortgage costs $3,484.43 a month and $227,197.30 in total interest, while a 30-year mortgage costs $2,528.27 a month and $510,177.95 in total interest. The 15-year costs $956.16 more every month — but saves $282,980.65 in interest and gets you out of debt 15 years sooner.
That single trade-off — $956.16 a month now versus $282,980.65 later — is the whole decision. This guide compares the two terms payment by payment, shows how fast each one builds equity, and explains who should pick which, including a hybrid strategy that gets you most of the 15-year savings with the 30-year’s safety net.
The Headline Numbers: Same Loan, Two Terms
Same $400,000 loan, same 6.5% rate, two different terms:
| 15-year | 30-year | Difference | |
|---|---|---|---|
| Monthly payment | $3,484.43 | $2,528.27 | $956.16 |
| Total paid | $627,197.30 | $910,177.95 | $282,980.65 |
| Total interest | $227,197.30 | $510,177.95 | $282,980.65 |
| Time to pay off | 15 years | 30 years | 15 years |
The 30-year costs 45% more in total: $910,177.95 versus $627,197.30. Put another way, the 15-year borrower pays $227,197.30 in interest — about 57 cents per dollar borrowed — while the 30-year borrower pays $510,177.95, or about $1.28 per dollar borrowed. The 30-year borrower pays more in interest than the house itself cost.
But the monthly gap is real money too. $956.16 a month is $11,473.92 a year — a car payment, a childcare bill, or a serious retirement contribution. The question is never just “which is cheaper?” but “can I afford the higher payment without stress, every month, for 15 years?”
The Rate Advantage: 15-Year Loans Usually Cost Less
The comparison above holds the rate equal, but in practice 15-year mortgages usually carry a lower rate than 30-year mortgages — often about 0.5% lower. At 6% instead of 6.5%, the 15-year payment on $400,000 is $3,375.43 a month with $207,576.92 in total interest. Against the 30-year at 6.5%, the gap narrows to $847.16 a month, and the interest saved grows to $302,601.04.
That rate gap is not guaranteed — it moves with the market — but it is the normal pattern, because the lender gets its money back twice as fast and takes less risk. When you compare offers, compare the 15-year rate against the 30-year rate, not against each other at the same rate. Run both through a free mortgage calculator with each term’s actual quoted rate before you decide.
How Fast Does Each Term Build Equity?
Equity is the part of the home you actually own: the home’s value minus the remaining loan balance. The 15-year builds it far faster, because so much more of each payment goes to principal from the start.
| After | 15-year balance | 30-year balance | Equity gap |
|---|---|---|---|
| 5 years | $306,868.48 | $374,443.91 | $67,575.43 |
| 10 years | $178,084.59 | $339,104.51 | $161,019.92 |
| 15 years | $0.00 | $290,236.56 | $290,236.56 |
After 10 years, the 15-year borrower owes $178,084.59 — less than half the original loan — while the 30-year borrower still owes $339,104.51, or 85% of it. The equity gap at year 10 is $161,019.92. That equity is real wealth: it is what you keep when you sell, what you can borrow against, and what protects you if home prices fall. A 30-year borrower who needs to sell after five years has paid $151,696.20 in payments and still owes $374,443.91 — they have built only $25,556.09 of equity from payments. The month-by-month reason is simple: in month 1, the 15-year payment of $3,484.43 puts $1,317.76 toward principal, while the 30-year payment of $2,528.27 puts only $361.61 toward principal. Same interest charge of $2,166.67 in both cases — the difference is entirely in the principal.
Who Should Choose the 15-Year Mortgage?
The 15-year fits borrowers who can answer yes to all three of these:
- The payment fits comfortably. The $3,484.43 payment should pass the 28/36 rule on your income with room to spare — not just barely. Check your number with our guide to how much house can i afford before you commit. A payment that is fine in a good month and terrifying in a bad month is the wrong payment.
- You plan to stay. The savings only matter if you keep the loan. If you expect to move in five years, the 15-year still builds $67,575.43 more equity by year 5 — but the higher payment may have strained you for nothing if you sell early.
- Your other finances are in order. No high-interest debt, a full emergency fund, and retirement savings on track. Paying off a 6.5% mortgage early is a good return, but not if it means carrying 22% credit-card debt or skipping your employer’s 401(k) match.
If that is you, the 15-year is the cheaper loan by an enormous margin — $282,980.65 cheaper, before the rate advantage — and you own your home free and clear in half the time.
Who Should Choose the 30-Year Mortgage?
The 30-year fits almost everyone else, and there is no shame in it — it is the most popular mortgage in America for good reasons:
- Lower payment, more flexibility. $2,528.27 versus $3,484.43 leaves $956.16 a month for everything else life demands: childcare, savings, investing, or simply breathing room.
- Easier qualification. The lower payment means a lower debt-to-income ratio, which can be the difference between approval and denial — and between the home you want and the home you settle for.
- Inflation works for you. A $2,528.27 payment in year 25 is worth far less in real terms than the same payment today, because wages and prices rise while the payment stays fixed.
The honest risk of the 30-year is behavioral, not mathematical: the $956.16 a month you save has to actually go somewhere useful. If it gets spent, the 30-year costs you $282,980.65 for flexibility you never used.
The Hybrid: A 30-Year Loan Paid Like a 15-Year
There is a middle path that keeps the 30-year’s safety net and captures nearly all of the 15-year’s savings: take the 30-year mortgage, then pay the 15-year payment of $3,484.43 every month — an extra $956.16 on top of the required $2,528.27.
The result is almost identical to the real 15-year loan: the mortgage is paid off in 180 months, with $227,196.98 in total interest — a saving of $282,980.97 against the plain 30-year schedule. The difference from the true 15-year loan is 32 cents of interest, because the extra payments go straight to principal from month 1.
The advantage is flexibility. In a month when money is tight — a car repair, a medical bill, a gap between jobs — you can drop back to the required $2,528.27 with no penalty and no call to the lender. The 15-year borrower has no such option: $3,484.43 is due every month, good month or bad. The only cost of the hybrid is discipline, and one risk: the rate. A true 15-year loan usually carries a lower rate, so if the 15-year rate is meaningfully lower, the real 15-year still wins. Our guide to how to pay off your mortgage early works through extra-payment strategies in detail, including smaller amounts that still save five figures.
What About the 20-Year Mortgage?
The 20-year term splits the difference neatly: on the same $400,000 loan at 6.5%, the payment is $2,982.29 a month with $315,750.21 in total interest. Against the 30-year, that is $454.02 more a month and $194,427.74 less interest. It suits buyers who find the 15-year payment too steep but still want to retire the mortgage well before 30 years — and it is worth pricing whenever you compare terms, because lenders quote it less often and the rate usually sits between the 15- and 30-year rates.
How to Decide in Five Minutes
Work through these in order:
- Run the 28/36 rule. Find the maximum housing payment your income supports — our affordability guide walks through it.
- Price both terms. Get real quotes for the 15- and 30-year rates and run each through a monthly mortgage payment calculator.
- Stress-test the 15-year payment. Could you pay $3,484.43 every month for a year if your income dropped 20%? If not, the 30-year is the honest choice.
- Check the hybrid. If the 30-year payment fits easily but the 15-year payment is a stretch, plan the hybrid: pay extra when you can, fall back when you must.
- Look at your whole balance sheet. High-interest debt and missing emergency savings beat the mortgage every time — clear those first, then optimize the term.
FAQ: 15-Year vs 30-Year Mortgage
Is a 15-year mortgage always better than a 30-year?
Not always. The 15-year saves $282,980.65 in interest on a $400,000 loan at 6.5%, but it costs $956.16 more a month. If that higher payment strains your budget, the 30-year is the better choice — especially since you can pay a 30-year off in 15 years with extra payments.
How much do you save with a 15-year mortgage?
On a $400,000 loan at 6.5%, the 15-year saves $282,980.65 in interest versus the 30-year ($227,197.30 versus $510,177.95). If the 15-year rate is 6% instead of 6.5%, the saving grows to $302,601.04.
What is the monthly payment difference between a 15- and 30-year mortgage?
On a $400,000 loan at 6.5%, the 15-year payment is $3,484.43 and the 30-year payment is $2,528.27 — a difference of $956.16 a month, or $11,473.92 a year.
Can I pay off a 30-year mortgage in 15 years?
Yes. Paying the 15-year payment of $3,484.43 on a 30-year loan — an extra $956.16 a month — pays it off in 180 months with $227,196.98 in interest, virtually identical to the real 15-year loan. Just confirm your loan has no prepayment penalty first.
Does a 15-year mortgage build equity faster?
Much faster. After 10 years the 15-year balance is $178,084.59 versus $339,104.51 on the 30-year — an equity gap of $161,019.92 — because $1,317.76 of the first 15-year payment goes to principal versus $361.61 on the 30-year.
Is a 20-year mortgage a good compromise?
Often, yes. On a $400,000 loan at 6.5%, the 20-year payment is $2,982.29 with $315,750.21 in total interest — $454.02 more a month than the 30-year, saving $194,427.74 in interest.