Total mortgage interest paid over a period or across the full repayment schedule.
Total interest is the amount of mortgage interest paid over a specific period or across the full scheduled repayment life of the loan.
Total interest matters because a lower monthly payment does not always mean a cheaper mortgage over time. A longer loan term can reduce the payment but increase the number of months interest accrues. A shorter term can raise the payment but reduce total interest if the borrower can afford it.
The term helps borrowers compare the long-run cost of loan terms, rates, points, refinancing, and extra principal payments.
Borrowers encounter total-interest comparisons while shopping for loan terms, reviewing amortization schedules, comparing refinance options, and deciding whether to make extra principal payments.
The number can be calculated for the entire scheduled loan life or for a shorter comparison period, such as the expected time the borrower plans to keep the home.
| Factor | Typical effect |
|---|---|
| Higher interest rate | More interest accrues for the same balance and term |
| Longer loan term | More months of interest can accrue |
| Extra principal payments | Principal falls faster, which can reduce later interest |
| Refinance timing | A new rate or term can reduce or increase lifetime interest |
A borrower compares a 30-year fixed mortgage with a 15-year fixed mortgage. The 30-year loan has the lower monthly payment, but the 15-year loan may result in much less total interest if held to payoff.
Total interest differs from Interest because interest is the general cost of borrowing, while total interest is the accumulated amount paid over time.
It differs from Monthly Payment because the monthly payment is a periodic bill, while total interest measures cost across a period.
It also differs from APR because APR is a standardized annualized cost measure, while total interest is the actual dollar amount of interest over a chosen timeline.