Extra Mortgage Payment Calculator
What an extra payment saves in interest and years, and the truth about biweekly.
Biweekly is not a trick: 26 half-payments equal 13 monthly payments a year, so it is exactly one extra payment, or $169 a month here. Paying that directly achieves the identical result, and unlike many servicer biweekly programs it costs nothing to set up. Check that extra goes to principal, not toward next month.
Every dollar paid above the scheduled amount goes straight to principal, which removes all the future interest that dollar would have carried. On a long loan early in its life, that effect is large out of proportion to the amount.
Frequently asked questions
Should I pay off my mortgage early or invest?
Compare your mortgage rate against the after-tax return you expect elsewhere. A 3% mortgage is very hard to beat by prepaying when safe alternatives yield more; a 7% mortgage is a guaranteed 7% return, which is genuinely attractive. Prepaying is also risk-free and illiquid, which cuts both ways.
Does an extra payment lower my monthly payment?
No. It shortens the term instead. The scheduled payment stays the same and the loan simply ends sooner. If you want a lower payment you need a recast, which some servicers offer after a large principal reduction, or a refinance.
Is it better to pay extra early or later?
Much earlier. Early in a loan almost all of each payment is interest, so principal reductions remove the most future interest. The same extra dollar applied in year 25 saves very little, because there is barely any interest left to avoid.
What about the mortgage interest deduction?
Prepaying reduces the interest you pay and therefore any deduction you claim on it, but that is not an argument against prepaying. You never save a dollar of tax by spending more than a dollar of interest. It only matters if you itemize at all, which most households no longer do.
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Calculators model hypothetical outcomes from the inputs you provide. They are informational only, not financial, investment, tax, or legal advice.