Ask a lender what your monthly payment will be and they will usually quote principal and interest. Ask your bank account at the end of the month and you will get a bigger number. I broke one typical payment — $3,150.07 a month on a $400,000 home bought with 10% down — into its five real pieces: principal, interest, taxes, insurance and PMI. Once you can see each line for what it is, you can predict your own payment on any home, and you will know exactly when the most resented line, PMI, is legally required to disappear.

One payment, five pieces

The example: a $360,000 loan (10% down on a $400,000 home) at 7.40% for 30 years — the Freddie Mac survey average for the week of October 15, 2026. Taxes use the 0.9% national average effective property tax rate from ATTOM’s 2025 analysis ($3,600 a year); insurance uses the $2,490 national average annual premium from NerdWallet’s May 2026 analysis; PMI is an illustrative 0.50% of the loan amount per year. Your tax and insurance lines will differ from these averages — in high-tax states, by a lot.

P and I: the part that slowly changes sides

Principal and interest are the only pieces that actually pay for the house, and they are bundled into one fixed amount: $2,492.57 here. What changes is the split inside it. In month one, interest is $2,220.00 and principal just $272.57 — the lender collects its rent first. Month by month the balance falls, the interest shrinks, and the principal grows, until the final payment is almost all principal. Across the full term this loan repays $360,000 of principal and $537,321.39 of interest. When people say “my payment,” this P&I figure is usually the one they mean — and as the table shows, it understates the real monthly cost by $657.50 on this home.

T and I: the escrow passengers

Property taxes and homeowners insurance are not the lender’s money, but the lender collects them anyway. Each month, one-twelfth of your estimated annual tax bill ($300.00) and insurance premium ($207.50) goes into an escrow account alongside your P&I; when the county tax bill and the insurance renewal come due, your servicer pays them from that account. Federal rules cap the cushion your servicer can hold at two months of escrow charges.

Two practical consequences follow. First, a fixed-rate mortgage does not mean a fixed total payment: your servicer runs an escrow analysis every year, and when taxes or premiums rise, your monthly total rises with them. Homeowners insurance has been rising fast — industry analyses put the average premium up roughly 46% since 2021 — which is why so many owners with 3% pandemic-era rates have still watched their payments climb. Second, the T&I lines are local, not national: at New Jersey’s effective tax rates the tax line on this home could be two to three times the $300 average used here, while in Hawaii it could be a third of it.

PMI: the piece with an exit date

Private mortgage insurance protects the lender, not you, and exists because this loan started above 80% of the home’s value. People sometimes go looking for a standalone mortgage insurance calculator, but you do not need one: the premium is just a rate multiplied by your loan amount, and what actually matters is seeing it inside the whole payment, as in the table above. Freddie Mac estimates PMI typically runs $30 to $70 a month for every $100,000 borrowed; this example sits mid-range at $150 a month. Unlike taxes and insurance, though, PMI is temporary — and federal law (the Homeowners Protection Act, explained by the CFPB) gives it three separate exits:

• Ask at 80%: once your balance is scheduled to reach 80% of the home’s original value — month 105 on this loan, when the balance reaches $320,000 — you can request cancellation in writing, provided you are current, have a good recent payment history, and can show the value has not fallen.
• Automatic at 78%: if you do nothing, your servicer must terminate PMI when the balance is scheduled to reach 78% of original value — $312,000, in month 120 here — as long as you are current on payments.
• The midpoint backstop: if PMI has somehow survived to the halfway point of the loan term, it must end then regardless.

On this loan, waiting for the automatic date instead of asking at 80% costs 15 extra months of premiums — $2,250 left on the table for want of one letter. Extra principal payments pull both dates closer, and under Fannie Mae and Freddie Mac investor guidelines many servicers will also cancel PMI based on a new appraisal if your home has appreciated, which is a different — often faster — route than the original-value math above. One recent change worth knowing: since September 2026, Fannie Mae has expressly allowed servicers to proactively contact borrowers who look eligible to cancel. They may now tell you. They still cannot do the asking for you.

MIP: PMI’s stricter cousin

If the loan were FHA instead of conventional, the insurance line would be MIP rather than PMI, and the exit rules would be harsher: an upfront premium of 1.75% on top of the annual one, and — for down payments under 10% — no cancellation at any equity level, ever. The insurance runs for the life of the loan or until you refinance out of it. Same job, same monthly line item, very different contract.

Build your own PITI in four lines

Strip away the interface and a PITI calculator does exactly four additions. Do them once by hand and you will never misread one again:

1. Principal and interest: run your loan amount, rate and term through the mortgage calculator.
2. Taxes: home price × your local effective tax rate, divided by 12. (Start with 0.9% if you have no better figure — then look up your county.)
3. Insurance: get one real quote and divide the annual premium by 12. Quotes vary enough that averages are only a placeholder.
4. PMI: if you are putting less than 20% down, estimate the loan amount × 0.5% ÷ 12 until a lender quotes your actual premium.

Add the four numbers and you have the payment your bank account will actually see — the number to budget against, and the number to compare when lenders compete.

Sources: Consumer Financial Protection Bureau (CFPB) — Homeowners Protection Act PMI cancellation and termination rights, and escrow rules; ATTOM 2025 Property Tax Analysis (0.9% national average effective rate; $4,427 average single-family tax bill); NerdWallet homeowners insurance analysis, May 2026 ($2,490 national average premium); Freddie Mac Primary Mortgage Market Survey, week of October 15, 2026, and PMI cost estimate; Fannie Mae Lender Letter LL-2026-07 (September 2026). All payment figures recomputed cent by cent; PMI is an illustrative estimate.