Mortgage Calculator with Extra Payments

Most mortgage calculators show only principal and interest — but your real monthly bill is bigger. This free mortgage payment calculator with taxes and insurance estimates your true payment: principal and interest, property tax, homeowner's insurance, and PMI, all broken down line by line. Add an extra monthly payment to see exactly how many years you shave off the loan and how much interest you save.

How to Use the Mortgage Calculator

Six steps to your true monthly cost:

1. Enter the home price — the purchase price of the house or condo you are considering.
2. Set your down payment as a percentage. The 20% line matters: put down less and the calculator adds PMI automatically, as most conventional lenders charge it.
3. Type the annual interest rate you were quoted (or expect). Even a quarter point moves the payment noticeably on a large loan.
4. Pick the loan term. Thirty years is standard; 15- and 20-year terms raise the payment but slash total interest.
5. Add annual property tax and homeowner's insurance. Find tax figures on the county assessor's site or the listing; about 1% of the price per year is a reasonable guess. Your lender will require insurance before closing.
6. Leave the PMI rate at 0.5% unless your lender quoted a figure; it only applies under 20% down.
7. Try an extra monthly payment toward principal. Enter any amount — even $100 or $200 — and the results show your new payoff time, total interest with and without the extra, and the interest saved. Extra payments go straight against principal, so early in the loan they are at their most powerful.

Press Calculate Payment for the total plus a line-by-line breakdown — the same PITI structure your lender's loan estimate uses.

Mortgage Formula: How Your Payment Is Calculated

The principal-and-interest portion of your payment comes from the standard amortization formula. It spreads the loan evenly so the last payment retires the balance exactly:

Here P is the loan amount (home price minus down payment), r is the monthly interest rate (annual rate ÷ 12 ÷ 100), and n is the total number of payments (years × 12). Early payments are mostly interest and later ones mostly principal — the payment never changes on a fixed-rate loan, only the split does.

The other three pieces are simple divisions. Monthly property tax is your annual tax bill ÷ 12, monthly insurance is your annual premium ÷ 12, and monthly PMI is (loan amount × annual PMI rate) ÷ 12. The calculator adds all four together for the total you would actually pay each month.

Worked Example

Let us price a $400,000 home with 10% down, a 6.5% rate, and a 30-year term. Annual property tax is $6,000, insurance is $1,800, and the PMI rate is 0.5%:

Principal and interest alone are $2,275.44, but the real monthly outlay is $3,075.44 — $800 more. That hidden gap is the number your budget must handle.

Why Your Payment Drops When You Hit 20% Equity: PMI Cancellation

Private mortgage insurance protects your lender, not you — it covers them if you default. Because you pay for protection you never benefit from, PMI is the first cost to attack. Federal law (the Homeowners Protection Act) gives you two exits: at 80% of the home's original value you can request cancellation in writing, and at 78% the servicer must cancel it automatically, as long as you are current on payments.

Three ways to get there faster: send extra principal payments (even $100 a month shaves off years); let appreciation work — a new appraisal can prove 20% equity without extra payments; or refinance once you have 20% equity and capture a lower rate at the same time.

A related concept is escrow. Most lenders collect one-twelfth of your annual tax and insurance bills with each payment and pay those bills for you. Once a year the lender runs an escrow analysis: if taxes or premiums rose, your payment ticks up to cover the shortage; if they fell, you get a surplus refund. That is why payments drift slightly year to year even on "fixed" loans.

Limitations

This calculator estimates a fixed-rate conventional loan. It leaves out HOA dues, maintenance and repairs (budget roughly 1% of the home's value per year), utilities, and closing costs, and it assumes property tax and insurance stay flat — in reality both change yearly and your escrow payment gets adjusted. Adjustable-rate mortgages are not modeled. This is an estimate for planning, not a loan offer: your actual payment comes from your lender's official loan estimate. Treat this as guidance, not financial advice.

Sources & References

The disclosure documents this calculator mirrors — the Loan Estimate and Closing Disclosure — are standardized by the Consumer Financial Protection Bureau. Their guides explain each figure a lender will quote you:

• CFPB — Owning a Home: step-by-step guides and tools for the whole home-buying process, from comparing loan options to closing.
• CFPB — Loan Estimate explainer: how to read the standard three-page Loan Estimate every lender must give you within three business days of your application.

The mortgage is usually the biggest line in a household budget, which makes the small lines worth optimising too. The same maths mindset applies at the supermarket: our unit price comparison guide shows how to spot the genuinely cheaper pack, and if a pension sits alongside the mortgage, the 401(k) contribution limits for 2026 are worth checking before the year closes.

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