15 vs 30 Year Mortgage — Payment, Interest & Total Cost Comparison

15 vs 30 Year Mortgage

Compare a 15-year vs 30-year fixed mortgage. See the difference in monthly payment, total interest, and total cost. Optionally include taxes & insurance (escrow) for budget realism.

Loan Amount

Down Payment

If you enter a down payment, it subtracts from the loan amount.

15-Year Rate (%)

30-Year Rate (%)

Taxes & Insurance (Monthly, optional)

Property tax + homeowner’s insurance + (optionally) HOA dues.

Extra Principal (Monthly, optional)

Applied to both scenarios for apples-to-apples comparison.

Monthly Payment (15y)

Monthly Payment (30y)

Total Interest (15y)

Total Interest (30y)

Total Cost (15y)

Total Cost (30y)

View Amortization Highlights

Scenario	Term	Rate (nominal)	Payment (P&I)	Payment (PITI)	Total Interest	Total Cost	Years to Pay (with extra)

Formulas used

Monthly rate: i = r / 12
Payment (principal & interest): PMT = P · [ i / ( 1 − (1 + i)⁻ⁿ ) ]
Total interest: Interest = PMT · n − P
PITI: PITI = PMT + escrow

What to consider

15-year loans usually have lower rates but higher payments—significantly less interest overall.
30-year loans improve monthly cash flow but accumulate more interest over time.
Extra principal payments shorten term and reduce interest in both cases.

FAQ

Is the 15-year always better?

Purely on interest, yes; but affordability, emergency fund needs, and opportunity cost matter.

What about refinancing later?

If rates drop or income rises, refinancing a 30-year into a 15-year can capture savings.

Tool developed by Ugo Candido. Finance content reviewed by the CalcDomain Editorial Board.
Last accuracy review: October 23, 2025