A mortgage payment has four parts: principal, interest, taxes, and insurance — together called PITI. Principal and interest go to your lender, while property taxes and homeowners insurance are usually collected monthly into an escrow account. Understanding each piece helps you budget for your true housing cost, not just the loan payment.
Principal: the part that builds your equity
Principal is the actual loan balance you borrowed. Every month, a slice of your payment reduces that balance — and each reduction means you own a slightly bigger share of your home outright.
Early in a 30-year loan, the principal slice is surprisingly small because interest eats most of the payment. Over time the balance shrinks, the interest shrinks with it, and more of each payment builds your equity.
Interest: the price of borrowing
Interest is the lender's fee for letting you borrow hundreds of thousands of dollars. It is calculated on your remaining balance, which is why payments early in the loan are interest-heavy.
Your rate locks in this cost for the life of a fixed-rate loan. Even a half-point difference in rate changes total interest by tens of thousands of dollars, which is why shopping lenders before you buy matters so much.
Property taxes: the bill that changes yearly
Property taxes fund local services like schools and roads, and they are based on your home's assessed value. Unlike your loan payment, they are re-estimated regularly — often every year — so this slice of PITI moves.
Tax rates vary wildly by location: the same priced home can carry double the tax bill in one county versus another. When house hunting, always ask for the property's actual tax history, not just the listing price.
Insurance: protecting the home and the lender
Homeowners insurance protects against fire, storms, theft, and liability claims — and your lender requires it because the house is their collateral too. Premiums depend on your home's value, location, and coverage choices.
If your down payment was under 20%, you may also pay private mortgage insurance (PMI), which protects the lender — not you — until your equity reaches 20%. PMI is often bundled into the same monthly escrow collection.
Escrow: how your lender collects taxes and insurance
Most lenders collect taxes and insurance monthly and hold the money in an escrow account, then pay the actual bills when they come due. That is why your quoted mortgage payment is higher than principal plus interest alone.
Each year your lender re-analyzes escrow: if taxes rose, your monthly payment rises to cover the shortfall. Review the annual escrow statement carefully — errors in tax estimates are common and worth disputing.
Calculate your true monthly cost
Add all four PITI components — plus any HOA dues — to find your true monthly housing cost. A mortgage payment calculator estimates principal and interest, and you can layer in local tax rates and insurance quotes for the full picture.
Knowing the complete number matters beyond budgeting: it is the figure to weigh in the rent-versus-buy decision, and a bigger down payment — see our guide to saving for a down payment — shrinks both the loan and the insurance slice at once.
Frequently asked questions
Why did my mortgage payment go up if my rate is fixed?
Usually taxes or insurance. With a fixed-rate loan, your principal and interest never change — but property tax assessments rise, and homeowners insurance premiums creep up.
What is PMI and when does it drop off?
Private mortgage insurance protects the lender when your down payment is under 20%. It is typically required on conventional loans until your balance drops to 80% of the home's value, at which point you can request cancellation. It falls off automatically at 78% for most loans that started after mid-2013.
Can I pay my taxes and insurance myself instead of escrow?
Sometimes, if your lender allows it and you have enough equity — often 20% or more. Handling taxes and insurance yourself means saving for two large annual bills instead of paying monthly, so it demands discipline.
How much of my income should go to PITI?
A common guideline is the 28% rule: keep total PITI at or below 28% of your gross monthly income. Lenders use similar thresholds when approving loans.
Which parts of PITI can change over time?
Your principal and interest are fixed at closing for a fixed-rate loan. Taxes, insurance, and any PMI sit in escrow and get re-estimated yearly, so the escrow slice of your payment can rise or fall. Budget a cushion each year for that adjustment rather than assuming the payment is permanent.