How Mortgage Payments Are Calculated (PITI Explained)
See exactly how principal, interest, taxes, and insurance combine into your monthly mortgage payment, with a worked example and ways to lower it.
Your monthly mortgage payment is rarely a single, simple number. It is built from several moving parts, and understanding each one helps you see exactly where your money goes and how to reduce the total you pay over the life of the loan.
Below we break the payment down piece by piece, walk through a real worked example, and show you how to test your own numbers instantly with our Mortgage Calculator.
Try it right here — results update instantly.
The four parts of a payment (PITI)
Most mortgage payments are made up of four components, often abbreviated as PITI:
- Principal — the portion that pays down the amount you borrowed.
- Interest — the cost the lender charges for lending you the money.
- Taxes — property taxes collected and held in escrow.
- Insurance — homeowners insurance and, if applicable, private mortgage insurance (PMI).
Lenders typically collect taxes and insurance monthly and hold them in an escrow account, then pay the annual bills on your behalf when they come due.
The principal and interest formula
The core of your payment — principal and interest — is calculated with a standard amortization formula: M = P · r · (1 + r)^n ÷ ((1 + r)^n − 1), where P is the loan amount, r is the monthly interest rate (annual rate divided by 12), and n is the total number of monthly payments.
Worked example
Take a $300,000 loan at a 6.5% fixed rate over 30 years. The monthly rate is 6.5% ÷ 12 = 0.5417%, and there are 360 total payments.
- Monthly principal and interest: approximately $1,896
- Total interest paid over 30 years: approximately $382,633
- Total repaid over the life of the loan: approximately $682,633
Add estimated annual property taxes of $3,600 and homeowners insurance of $1,200, and the full PITI payment rises to roughly $2,296 per month.
How amortization changes over time
| Loan Year | Interest Share of Payment | Principal Share of Payment |
|---|---|---|
| Year 1 | ~96% | ~4% |
| Year 10 | ~78% | ~22% |
| Year 20 | ~46% | ~54% |
| Year 30 | ~4% | ~96% |
This is why refinancing or selling in the first few years leaves relatively little equity built from payments alone — most of what you have paid so far went to interest, not principal.
How to lower your payment
- Increase your down payment to borrow less and possibly avoid PMI.
- Shop lenders — even a 0.25% lower rate adds up over 30 years.
- Choose a longer term for lower monthly payments (but more total interest).
- Improve your credit score before applying to qualify for better rates.
- Make extra principal payments to shorten the loan and cut interest.
- Ask about removing PMI once you reach 20% equity.
Common mistakes to avoid
- Comparing only the interest rate and ignoring the APR, which includes fees.
- Forgetting to budget for property taxes and insurance on top of principal and interest.
- Assuming a pre-approval amount is what you should actually spend.
- Not checking whether PMI can be removed later and under what conditions.
- Skipping a rate comparison across at least three lenders.
Frequently Asked Questions
What does PITI stand for?
Principal, Interest, Taxes, and Insurance — the four components most lenders bundle into a single monthly mortgage payment.
Why is most of my early payment interest?
Amortization schedules front-load interest because it is calculated on the outstanding balance, which is highest at the start of the loan.
Can I remove PMI from my payment?
Yes, once your loan balance falls to 80% of the home's original value, you can typically request PMI removal, and it is automatically cancelled at 78%.
Does a longer loan term always cost more overall?
Yes. Extending the term lowers the monthly payment but increases the total interest paid over the life of the loan.
How much do extra principal payments actually save?
Even modest extra payments made early can shave years off a 30-year loan and save tens of thousands of dollars in interest — try it in our calculator.
Are property taxes included automatically?
Only if you choose to include them; our Mortgage Calculator lets you add taxes and insurance to see the full PITI estimate.
What is escrow?
An escrow account is where your lender holds the portion of your payment set aside for taxes and insurance until those bills are due.
Is a fixed or adjustable rate better?
Fixed rates keep your principal and interest payment constant for the full term, while adjustable rates can rise or fall after an initial period — fixed rates are generally lower-risk for long-term homeowners.
Related Calculators
- Mortgage Calculator
- Loan Calculator
- Amortization Calculator
- Interest Calculator
- Browse all Financial Calculators or the full All Calculators directory.
Final thoughts
Once you understand how principal, interest, taxes, and insurance fit together, a mortgage statement stops feeling like a black box. Use our Mortgage Calculator to run your own numbers, test a bigger down payment, or see how extra payments shorten your loan.
Try it yourself
Put this guide into practice with our free tool.
CalcWisee Editorial Team
Calculator development and formula review
CalcWisee is an independent site founded by Ayman. Every calculator is built from a published formula or official definition, tested against hand-worked examples before it goes live, and corrected promptly when a reader reports an issue to ayman@calcwisee.com.
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