15 vs 30 Year Mortgage Comparison Calculator
Compare a 15-year and 30-year mortgage side by side. See how a shorter term means higher monthly payments but dramatically lower total interest, or how a 30-year term keeps payments affordable. Enter your home details below for an instant comparison.
Comparison Calculator Inputs
Enter Loan Details
Your Comparison Results
15-Year Monthly Payment
- 15-Year Total Monthly Payment
- $2,775.15 /mo
- P&I
- $2,325.15
- Rate
- 5.750%
- Total Interest
- $138,527
- Payoff Date
- March 2041
30-Year Monthly Payment
- 30-Year Total Monthly Payment
- $2,219.79 /mo
- P&I
- $1,769.79
- Rate
- 6.500%
- Total Interest
- $357,124
- Payoff Date
- March 2056
Monthly Payment Difference
$555.36 /mo more with 15-year
Total Interest Savings
$218,597 saved with 15-year
Detailed Comparison
| 15-Year | 30-Year | |
|---|---|---|
| Down Payment | $70,000 (20.0%) | $70,000 (20.0%) |
| Loan Amount | $280,000 | $280,000 |
| Interest Rate | 5.750% | 6.500% |
| Monthly P&I | $2,325.15 | $1,769.79 |
| Monthly PITI | $2,775.15 | $2,219.79 |
| Total Interest Paid | $138,527 | $357,124 |
| Total Cost (P&I + Escrow) | $499,527 | $799,124 |
| Payoff Date | March 2041 | March 2056 |
Payment Breakdown
Equity Buildup Over Time
| Year | 15-Year Equity | 30-Year Equity |
|---|---|---|
| 1 | $82,118 | $73,130 |
| 2 | $94,951 | $76,469 |
| 3 | $108,542 | $80,032 |
| 4 | $122,935 | $83,833 |
| 5 | $138,179 | $87,889 |
| 6 | $154,322 | $92,217 |
| 7 | $171,418 | $96,834 |
| 8 | $189,523 | $101,761 |
| 9 | $208,698 | $107,018 |
| 10 | $229,004 | $112,627 |
| 11 | $250,510 | $118,611 |
| 12 | $273,285 | $124,996 |
| 13 | $297,405 | $131,809 |
| 14 | $322,949 | $139,078 |
| 15 | $350,000 | $146,834 |
| 16 | $350,000 | $155,110 |
| 17 | $350,000 | $163,939 |
| 18 | $350,000 | $173,360 |
| 19 | $350,000 | $183,412 |
| 20 | $350,000 | $194,137 |
| 21 | $350,000 | $205,580 |
| 22 | $350,000 | $217,790 |
| 23 | $350,000 | $230,817 |
| 24 | $350,000 | $244,717 |
| 25 | $350,000 | $259,548 |
| 26 | $350,000 | $275,372 |
| 27 | $350,000 | $292,256 |
| 28 | $350,000 | $310,270 |
| 29 | $350,000 | $329,491 |
| 30 | $350,000 | $350,000 |
15-Year vs 30-Year Mortgage: Which Is Better?
There is no universally "better" option — the right choice depends on your financial goals, monthly cash flow, and risk tolerance. A 15-year mortgage offers significant interest savings and faster equity building, but comes with higher monthly payments. A 30-year mortgage provides lower monthly payments and more financial flexibility, but costs considerably more in total interest.
The key trade-off is straightforward: with a 15-year mortgage you commit to higher monthly payments in exchange for lower total cost. With a 30-year mortgage you get breathing room in your monthly budget but pay more over the life of the loan. Most financial advisors suggest that if you can comfortably afford the higher payment without straining your budget, the 15-year option is mathematically superior.
How the Math Works
Both mortgage types use the same standard amortization formula to calculate monthly principal and interest:
M = P × [r(1+r)n] / [(1+r)n − 1]
The 15-year mortgage has two advantages in this formula: a lower interest rate (r) and fewer total payments (n = 180 vs 360). While fewer payments means each payment must cover more principal — driving the monthly amount up — the dramatically shorter payback period means you pay far less in cumulative interest. The rate advantage compounds this effect: even a 0.5–0.75% lower rate on the 15-year term results in substantial additional savings.
Example: $350,000 Home at Current Rates
Using the current inputs — a $350,000 home with $70,000 down (20%), here's how the two options compare:
15-Year at 5.750%
- Monthly P&I: $2,325.15
- Monthly PITI: $2,775.15
- Total interest: $138,527
- Paid off: March 2041
30-Year at 6.500%
- Monthly P&I: $1,769.79
- Monthly PITI: $2,219.79
- Total interest: $357,124
- Paid off: March 2056
The 15-year option costs $555.36 more per month, but saves $218,597 in total interest over the life of the loan. That's 61% less interest paid.
When to Choose 15 Years vs 30 Years
Choose a 15-Year Mortgage When:
- You can comfortably afford the higher monthly payment (keep housing under 28% of gross income)
- You want to be mortgage-free sooner, especially before retirement
- You want to build equity quickly for future financial leverage
- You want to pay the least total interest over the life of the loan
- You have a stable income and strong emergency fund
- Interest rates are favorable and you want to lock in savings
Choose a 30-Year Mortgage When:
- You need a lower monthly payment to qualify or stay comfortable
- You want maximum flexibility in your monthly budget
- You plan to invest the monthly savings elsewhere for potentially higher returns
- Your income may fluctuate (freelancers, commission-based roles)
- You're buying in a high-cost area where 15-year payments would be a stretch
- You plan to make extra payments when possible (hybrid approach)
The Middle Ground: 30-Year with Extra Payments
Many homeowners opt for a 30-year mortgage but make extra payments toward principal when their budget allows. This hybrid approach offers the safety of lower required payments during tight months, while still reducing total interest when extra cash is available.
For example, if you took the 30-year mortgage at 6.500% but added $555/month in extra principal payments (the difference in P&I between the two terms), you would pay off the loan significantly earlier than 30 years — though not quite as fast as a true 15-year, since the 30-year carries a higher interest rate.
The key advantage: if you hit a financial rough patch, you can stop the extra payments and fall back to the required 30-year minimum. With a 15-year mortgage, the higher payment is mandatory every month regardless of your circumstances.
Use our Extra Payment Calculator to see exactly how additional payments would affect your 30-year mortgage payoff timeline.
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Frequently Asked Questions
Is a 15-year mortgage better than a 30-year?
Neither is universally better — it depends on your situation. A 15-year mortgage saves significantly on total interest and builds equity faster, but requires higher monthly payments. A 30-year mortgage offers lower payments and more flexibility. If you can comfortably afford the 15-year payment while maintaining an emergency fund and retirement savings, it's generally the better financial choice.
How much more is a 15-year mortgage payment than a 30-year?
The 15-year payment is typically 40–60% higher than the 30-year payment for the same loan amount. The exact difference depends on the interest rates for each term and the loan size. Despite the higher monthly cost, the 15-year term dramatically reduces total interest — often by 50–70% or more.
Why are 15-year mortgage rates lower than 30-year rates?
Lenders charge lower rates on 15-year mortgages because they carry less risk. The shorter repayment period means the lender's money is tied up for less time and there's less exposure to potential defaults, inflation, and interest rate changes. The rate difference is typically 0.5% to 0.75%, though it varies with market conditions.
Can I refinance from a 30-year to a 15-year mortgage?
Yes, this is a common refinancing strategy. If you've had your 30-year mortgage for several years and your income has grown, refinancing to a 15-year can make sense — especially if rates have dropped. You'll get a lower rate and pay off the remaining balance faster. Use our Refinance Calculator to see if the numbers work for your situation.
Should I invest the payment difference instead of choosing a 15-year?
This is a valid strategy if you're disciplined about investing the difference. If the after-tax investment return exceeds the mortgage interest rate, you come out ahead financially with a 30-year. However, this approach carries market risk — stock returns aren't guaranteed, while mortgage interest savings are certain. The psychological benefit of being mortgage-free also has real value that's hard to quantify.
Does a 15-year mortgage build equity faster?
Yes, dramatically. A 15-year mortgage builds equity roughly twice as fast as a 30-year for two reasons: first, a larger portion of each payment goes to principal (because less goes to interest at the lower rate); second, you make larger payments overall. After 5 years on a 15-year mortgage, you'll typically have 25–30% equity, compared to 8–12% on a 30-year (excluding any home price appreciation).
What income do I need for a 15-year mortgage?
Most lenders follow the 28% rule: your total monthly housing payment (PITI) should not exceed 28% of your gross monthly income. For the current 15-year PITI payment of $2,775.15, you'd need a gross monthly income of at least $9,911 (about $118,935/year). Use our Affordability Calculator for a more detailed analysis.
How accurate is this 15 vs 30 year calculator?
The P&I calculations use the standard amortization formula and are accurate to the cent for fixed-rate loans. Property tax and insurance estimates are based on the rates you enter. PMI is estimated at 0.7% annually when the down payment is below 20% — actual PMI rates vary by lender, credit score, and loan-to-value ratio. This calculator does not account for closing costs, HOA fees, or adjustable-rate adjustments.