A mortgage payment is rarely just principal and interest. This adds property tax, homeowners insurance and PMI on top, so the number you see is the number you’ll actually pay each month.
How it works
Principal & interest, plus the rest
M = P × r(1+r)ⁿ ÷ ((1+r)ⁿ − 1)
The same standard amortization formula the loan amortization calculator uses. Property tax, insurance and PMI are simply added to that figure.
PMI is not permanent
Private mortgage insurance is typically required below 20% down. Under the US Homeowners Protection Act, lenders must automatically terminate it once the loan balance reaches 78% of the home’s original value on the amortization schedule — worth knowing, since PMI charged past that point is money that should have stopped. This calculator estimates PMI as a flat monthly rate and doesn’t model its automatic cutoff; treat the figure as applying only while it’s actually still owed.
How to use this calculator
- Enter the loan amount, rate and term.
- Add your estimated monthly property tax and insurance.
- Include PMI if you’re putting down less than 20%.
Frequently asked questions
Why does my quoted rate not match my full monthly payment?
Because the quoted rate applies only to principal and interest — taxes and insurance are separate costs a lender typically collects alongside the loan payment through an escrow account, even though they aren’t part of the loan itself.
How is property tax estimated if I don’t know my exact rate?
Check your specific county or municipality’s rate, or look at the current tax bill for the property if buying an existing home — property tax varies enormously by location, so this calculator asks for the monthly figure directly rather than guessing.
When exactly does PMI go away?
Federal law requires automatic termination at 78% of original value on the scheduled amortization curve. You can often request cancellation earlier, once you believe you’ve reached 80% equity through payments or appreciation — that request is on you to make, not automatic.
Does a bigger down payment always avoid PMI?
20% down is the common threshold most conventional lenders use, though the exact rule can vary by loan type and lender.
How is this different from the home affordability calculator?
This takes a loan amount as given and works out the payment. The home affordability calculator works backward from your income to a sustainable loan size in the first place.
