PITI & Escrow Explained: Why Your Mortgage Payment Changes

Every year, thousands of homeowners with fixed-rate mortgages open a letter saying their monthly payment is going up — and assume something went wrong. Usually nothing did. Only two of the four parts of your payment are actually fixed. Understanding PITI and escrow explains the other two, and why your payment moves even when your rate never does.

The Four Parts: Principal, Interest, Taxes, Insurance

• Principal: The part of your payment that reduces your loan balance. Small at first, growing every month as interest shrinks.
• Interest: The lender's charge, computed on your remaining balance. Large at first, shrinking as you pay down.
• Taxes: Your property taxes, collected monthly and paid to your county or city. These rise when assessments or tax rates rise.
• Insurance: Your homeowners insurance premium, also collected monthly. This rises with insurer rate increases and rebuilding costs.

Principal and interest are fixed for the life of a fixed-rate loan. Taxes and insurance are not — and on a typical loan they make up a third or more of the payment, which is why the total moves.

How Escrow Works

Most lenders require an escrow account. Each month you pay one-twelfth of your annual property tax bill plus one-twelfth of your annual insurance premium into escrow, and the servicer pays those bills when they come due. Lenders may also hold a cushion of up to two months of escrow payments, collected at closing.

Once a year, the servicer performs an escrow analysis: it compares what it collected against what it actually paid, projects the next year, and adjusts your monthly payment. That annual letter is where most payment surprises come from.

Why Payments Jump

• Tax reassessment: Your county raises your home's assessed value, sometimes sharply after a purchase or a hot market.
• Insurance increases: Premiums have risen steeply in many states due to disaster risk and rebuilding costs.
• Escrow shortage: If last year's bills exceeded collections, the shortfall is usually spread over the next 12 payments — so your payment jumps twice over: higher bills plus the shortage catch-up.
• Escrow surplus: The pleasant version — collections exceeded bills, and you get a refund check plus a slightly lower payment.

If a jump looks wrong, ask the servicer for the escrow analysis statement and check the tax and insurance figures against your actual bills. Errors happen, and servicers must correct them.

Worked Example: A $400,000 Home, Then a Tax Hike

Take a $400,000 home with 20% down and a $320,000 loan at 6.5% for 30 years. The Mortgage Calculator gives principal and interest of about $2,023 per month. Property taxes at 1.2% of the price are $4,800 a year ($400 per month), and insurance is $1,800 a year ($150 per month). Total PITI: about $2,573 per month, of which $550 a month goes into escrow. At closing, the lender also collects a two-month escrow cushion of about $1,100.

Now suppose the county reassesses and taxes rise 20% (to $480 per month) and insurance rises 15% (to about $173 per month). The new PITI is about $2,675 per month — up $102 even though the rate never moved. Worse, if the increase hit mid-year, escrow comes up short: say $600 short. The servicer spreads it over 12 months, adding $50 a month, so the payment temporarily reaches about $2,725 until the shortage is repaid. None of this is a rate change, a mistake, or a penalty — it is escrow doing exactly what it is designed to do, just in an unwelcome direction.

To see how your own payment breaks down, run your numbers through the Mortgage Calculator and the Home Affordability Calculator — both split out the tax and insurance portions so you can see how much of your payment is actually exposed to annual increases.