Compare 15-year vs 30-year mortgage payments, total interest, and savings side by side. See how much you save with a shorter term and decide which is right for you.
The choice between a 15-year and 30-year mortgage is one of the most consequential financial decisions homebuyers face. A 15-year term means significantly higher monthly payments but a lower interest rate and dramatically less total interest — often saving more than $100,000 on a typical home loan. A 30-year term provides lower, more manageable payments but costs substantially more over the life of the loan. Beyond the monthly payment, the term you choose affects how quickly you build home equity, your tax deductions, and how much financial flexibility you retain each month.
This side-by-side comparison calculator lets you enter a single loan amount and see both options at their respective rates. You will instantly see the monthly payment difference, the total interest for each term, and the lifetime savings from choosing the shorter option. The results update in real time as you adjust your inputs, making it easy to test different scenarios.
Most financial advisors agree that a 15-year term is mathematically superior — but only if you can comfortably afford the higher payment without straining your monthly budget. This tool helps you make that decision with hard numbers.
Knowing the monthly payment difference is easy — but understanding the total interest savings is eye-opening. On a $350,000 loan, the 15-year mortgage can save $150,000 or more in interest compared to a 30-year. This calculator shows both the monthly cost and the lifetime picture so you can make an informed decision.
If the 15-year payment seems too high, consider a 20-year or 25-year term as a compromise, or use a 30-year term with extra payments to mimic a shorter payoff.
M = P × [r(1+r)^n] / [(1+r)^n − 1] Applied twice: 15-year: n₁ = 180 months, r₁ = 15yr rate / 12 / 100 30-year: n₂ = 360 months, r₂ = 30yr rate / 12 / 100 Savings = Total Interest (30yr) − Total Interest (15yr)
Result: 15yr: $2,907/mo | 30yr: $2,212/mo | Save $226,750
A $350,000 loan at 5.75% over 15 years costs $2,907/month with $173,255 total interest. The same loan at 6.5% over 30 years costs $2,212/month — $695 less per month — but accrues $446,288 in total interest. Choosing the 15-year term saves $273,033 in interest but requires $695 more per month. If you can afford it, the 15-year is the clear winner on total cost.
The appeal of a 30-year mortgage is the lower monthly payment, but the total cost is staggering. On a $350,000 loan at 6.5%, you pay $446,288 in interest — more than the loan itself. The first five years of payments are roughly 80% interest and only 20% principal. Compare this to a 15-year at 5.75% where total interest is $173,255 — less than half the loan amount.
A 15-year mortgage is one of the most reliable wealth-building tools available. By year 10, you own roughly 70% of your home, compared to about 25% on a 30-year. This equity can fund retirement, provide a line of credit for emergencies, or give you a strong position for trading up to a larger home.
The strongest argument for a 30-year mortgage is flexibility, not cost. Life is unpredictable — job loss, medical bills, or family changes can strain budgets. A 30-year loan gives you a lower required payment, with the option to pay extra when times are good. This safety net can prevent foreclosure during financial hardship.
Savings depend on the loan amount and rates, but a 15-year typically saves 50-60% of the total interest compared to a 30-year. On a $350,000 loan, that can exceed $200,000 in savings.
Lenders charge lower rates on 15-year mortgages because they are repaid faster, meaning less risk of default, less interest-rate risk, and shorter capital commitment. The rate difference is typically 0.50-0.75%.
Financial advisors recommend that total housing costs stay below 28% of gross income. If the 15-year payment pushes you above that threshold, a 30-year with extra payments gives you the flexibility to reduce payments if your situation changes.
These middle-ground options offer lower payments than 15-year but less total interest than 30-year. A 20-year mortgage typically has a rate close to the 15-year and saves substantial interest. Not all lenders advertise them, but they are usually available on request.
If you take a 30-year loan and invest the monthly savings ($695 in our example) at 8% average returns, you might accumulate more wealth than the interest savings. However, investment returns are not guaranteed, while interest savings are. Your risk tolerance should guide this decision.
This hybrid approach gives you flexibility: you can make 15-year-level payments when finances are good and revert to the minimum when they are tight. The downside is you do not get the lower 15-year rate, so your effective savings are slightly less.
With a 15-year mortgage, you build equity roughly twice as fast because more of each payment goes to principal. After 5 years on a $350,000 loan, you might have $90,000 in equity on a 15-year vs $35,000 on a 30-year — a significant difference.
The mortgage interest deduction reduces the effective cost of interest, which slightly favors the 30-year (more interest = larger deduction). However, with the higher standard deduction, many borrowers no longer itemize, reducing this advantage.