Extra Mortgage Payment Calculator: Payoff Date and Savings

How to use it

Enter your current balance, rate and the number of payments left (your statement shows the balance; payments left is the original number minus those you have made). Then add any combination of:

• An extra amount every month, added to each payment.
• An extra amount once a year, applied with every 12th payment, for example from a bonus or tax refund.
• A one-time extra payment now.

How the savings are calculated

The calculator runs your loan twice, month by month. Both runs charge interest on the current balance at the monthly rate and apply the regular payment. The second run also subtracts your extra amounts from principal in the months you chose. When the balance hits zero, it stops and compares the number of payments and the total interest.

Before you pay extra

• Prepayment penalties. The CFPB says not all mortgages have one, and those that do usually apply when you pay off the whole loan within the first few years. Small extra principal payments normally don't trigger them, but check with your lender.
• Make sure it goes to principal. Many servicers have a separate box or online option for extra principal. Without it, extra money may be held as an early next payment.
• Compare with your other debts. Each extra dollar on a 6% mortgage saves 6% a year in interest. A dollar on a debt with a higher rate saves more.
• Keep an emergency fund. Money paid into the house is hard to get back without selling or borrowing.
• Other uses of the money. People also weigh savings goals such as an employer retirement match. This calculator only measures the interest side.

Biweekly plans

Paying half the monthly amount every two weeks makes 26 half-payments a year, the same as 13 monthly payments, which is close to the "one extra payment a year" row above. You can get the same effect yourself by adding one-twelfth of a payment each month. Some third-party biweekly services charge fees for this, which reduce the savings.

The figures here are educational estimates. Your servicer's records decide your actual payoff.

Common questions

Is it better to pay extra monthly or once a year?

Earlier is slightly better, because principal paid sooner stops accruing interest sooner. In practice, the total extra amount matters most.

Does paying extra lower my monthly payment?

Usually not. On most fixed-rate loans the required payment stays the same and the loan simply ends sooner. Some servicers offer a recast, which re-figures the payment after a large lump sum, often for a fee.

Will extra payments help me drop PMI?

They can. The CFPB explains that you can ask to cancel PMI once extra payments bring the balance to 80% of the home's original value, ahead of schedule.