The short version
Key takeaways
- Your monthly payment usually covers principal, interest, property taxes and homeowners insurance — often called PITI.
- A 15-year loan costs more per month than a 30-year loan but can save a very large amount of interest.
- Putting less than 20% down on a conventional loan usually means paying private mortgage insurance until you reach enough equity.
- Compare Loan Estimates from several lenders — they use a standard format, so offers line up side by side.
For most people, a mortgage is the largest loan they'll ever take on — and the one that stays with them the longest. Understanding how it works before you start house-hunting can save you tens of thousands of dollars and a lot of stress at the closing table.
This guide covers the essentials: what's in a mortgage payment, how rates and loan types differ, what a down payment really changes, and what happens between "offer accepted" and "keys in hand."
The basics
A mortgage is a loan used to buy a home, with the home itself serving as collateral. If you stop making payments, the lender can foreclose and sell the property to recover its money.
Most mortgages are repaid over 15 or 30 years in equal monthly installments. Each payment covers interest for that month plus a portion of the principal — the amount you borrowed. Early on, most of each payment goes to interest. Over time, the balance shifts toward principal. This schedule is called amortization.
What's in your monthly payment
Lenders often describe the full payment as PITI:
- Principal — repaying the amount borrowed
- Interest — the cost of borrowing
- Taxes — property taxes, usually collected monthly and paid by the lender from an escrow account
- Insurance — homeowners insurance, also usually paid through escrow
Depending on your situation, the payment may also include mortgage insurance and HOA dues.
Fixed-rate vs. adjustable-rate
Fixed-rate mortgages
The interest rate never changes for the life of the loan. Your principal and interest payment is the same in year 1 and year 30. Predictability is the main appeal.
Adjustable-rate mortgages (ARMs)
An ARM has a fixed rate for an initial period — often 5, 7 or 10 years — and then adjusts periodically based on a market index plus a set margin. A "5/6 ARM," for example, is fixed for five years and then adjusts every six months.
ARMs often start with a lower rate than fixed loans. The trade-off is uncertainty: after the fixed period your payment could rise, within the caps written into the loan.
15-year vs. 30-year: the real cost difference
The term changes both your monthly payment and the total interest you'll pay.
A middle path: take a 30-year loan for flexibility and make extra principal payments when you can.
Common loan types
| Loan type | Who it's for | Down payment |
|---|---|---|
| Conventional | Borrowers with solid credit; not government-backed | As little as 3% on some programs |
| FHA | Borrowers with lower scores or smaller down payments | As little as 3.5% with a qualifying score |
| VA | Eligible service members, veterans and some surviving spouses | Often 0% |
| USDA | Eligible buyers in qualifying rural and some suburban areas | Often 0% |
| Jumbo | Loans above the conforming limit for the area | Usually larger |
Down payments and mortgage insurance
A bigger down payment means a smaller loan, a lower payment and less interest. But waiting years to save 20% isn't always the best choice — home prices and rent don't stand still.
If you put down less than 20% on a conventional loan, you'll typically pay private mortgage insurance (PMI). It protects the lender, not you. The good news: under federal law, you can request cancellation once your balance reaches 80% of the home's original value, and it generally ends automatically at 78%, provided you're current on payments.
FHA loans have their own mortgage insurance premium (MIP), which works differently and, for many borrowers with smaller down payments, lasts for the life of the loan unless you refinance.
How much house can you afford?
Lenders look closely at your debt-to-income ratio, your credit score, your down payment and your savings. A traditional guideline is to keep your housing payment at or below about 28% of gross monthly income and total debt payments at or below 36%.
Don't stop at what the lender approves. Budget for maintenance and repairs, utilities, and an emergency fund that doesn't disappear into the down payment.
The mortgage process, step by step
- Check your credit and give yourself time to fix any errors.
- Get pre-approved. You'll provide income, asset and debt documentation; the lender checks your credit and issues a conditional approval amount.
- Shop lenders. Within three business days of a full application, each lender must give you a Loan Estimate — a standardized form that makes offers easy to compare. Multiple mortgage inquiries within a short window are generally treated as one for credit scoring.
- Make an offer and sign a purchase agreement.
- Lock your rate. A rate lock holds your rate for a set period while the loan is finalized.
- Underwriting, appraisal and inspection. The lender verifies everything and orders an appraisal. A home inspection, arranged by you, checks the property's condition.
- Review your Closing Disclosure. You must receive it at least three business days before closing. Compare it line by line with your Loan Estimate.
- Close. Sign the documents, pay closing costs and your down payment, and get the keys.
Closing costs
Expect closing costs of roughly 2% to 5% of the loan amount. They can include lender origination fees, appraisal and credit report fees, title insurance, recording fees, prepaid interest, and the initial deposits into your escrow account. Some can be negotiated or offset with lender credits — at the cost of a slightly higher rate. Our guide to mortgage points explains that trade-off.
The bottom line
A mortgage is really several decisions bundled together: the loan type, the term, the rate structure, the down payment and the lender. Take them one at a time, compare Loan Estimates from at least three lenders, and choose a payment that leaves room for the rest of your life — not just the one the lender says you qualify for.
Quick answers
Frequently asked questions
How much do I need for a down payment?
Less than many people think. Some conventional loans allow 3% down, FHA loans can require as little as 3.5% with a qualifying credit score, and VA and USDA loans can require no down payment for eligible borrowers. A smaller down payment usually means mortgage insurance and a larger loan.
What's the difference between pre-qualification and pre-approval?
Pre-qualification is an informal estimate based on what you tell a lender. Pre-approval involves documentation and a credit check, and results in a conditional commitment — it carries more weight with sellers.
How much are closing costs?
They vary by location and loan, but are commonly in the range of 2% to 5% of the loan amount. Your Loan Estimate lists them in detail.
Can I pay my mortgage off early?
Most modern mortgages allow it without penalty, but check your loan documents. Even small extra principal payments can shorten the loan and reduce total interest.