Mortgage Payoff Calculator: extra payments, PMI and prepay vs invest

Your mortgage

Quick start

These five give you a full answer. The rest uses typical assumptions; open the sections below to fine-tune.

Loan balance today for a new loan, the amount borrowed

Interest rate yearly, from your statement

Years left on the loan 30 for a new 30-year loan

yrs

Next payment month payment 1 of the plan

Extra toward principal every month

Extra lump-sum payments

Bonuses, tax refunds or any other money sent straight to principal.

Repeating

Amount each time

First one in

Repeats

One-off payments

Any other amount at any time: an inheritance, a sale, a bigger bonus one year.

Escrow and PMI

Escrow /mo, property tax and insurance

Shown in your monthly payment; it doesn't change the payoff date. If it changes, come back and update your numbers from your latest statement.

PMI /mo, 0 if none

Usually charged when you put down less than 20%.

Price you paid for the home sets when PMI ends

I'll ask my lender to cancel PMI at 80%

By law PMI ends automatically when the original schedule reaches 78% of the price you paid. Extra payments only bring it forward if you ask to cancel at 80%.

Invest instead

Investment return /yr, before inflation

Tax on investment gains 15% is typical

Tax saved on mortgage interest 0 if you take the standard deduction

Only if you itemize: your top tax rate. Most households don't itemize.

Loan balance, with and without your extra payments

With extra payments Scheduled payments only PMI ends Debt-free

Year-by-year interest, principal, extra payments, PMI and balance
Year	Interest	Principal	of which extra	PMI	Balance	Without extras

Which extra payments do the work

Debt-free date and interest for each combination of extra payments
Plan	Debt-free	Total interest	Interest saved

Pay down the loan, or invest the money?

Investments left when the scheduled loan would have ended, prepaying versus investing
If investments earn	Prepay, then invest	Invest the extras	Ahead