What Makes Up Your Mortgage Payment (PITI)
Lenders quote you a rate, but you pay a payment — and the two aren't the same thing. A mortgage payment is built from four parts that go by the shorthand PITI: principal, interest, taxes, and insurance. Knowing which piece is which tells you what you can change and what you can't.
P and I — the loan itself
Principal is the slice that pays down what you borrowed; interest is the lender's charge on the balance. Together they're the "P&I," the only part your rate and term actually set — and the part a calculator computes. Early on, most of each payment is interest; as the balance falls, the mix tilts toward principal. That shift is amortization.
T and I — the parts that aren't really the loan
Taxes and insurance are property costs the lender collects alongside P&I and holds in escrow to pay on your behalf. They have nothing to do with your rate — which is exactly why two loans at the same rate can carry very different payments in different counties. When people say a "fixed" payment went up, it's almost always T or I moving, not P&I.
The extras: MI and HOA
Two more can ride along. If you put less than 20% down, mortgage insurance is added until you can remove it. And if your home is in an association, HOA dues are a separate bill — not part of PITI and not escrowed, but very real in your monthly budget.
By L.W. Martin, Founder — 20 years in the mortgage business, including 15 running his own brokerage. About → · Updated August 2026.