A mortgage is a loan you take out to buy a house or property, where the property itself serves as collateral

When you borrow money to purchase a home, the lender (usually a bank or mortgage company) gives you the full purchase price upfront. You then repay that money over time—typically 15 to 30 years—in monthly payments that include both principal (the amount you borrowed) and interest (the lender's fee for lending to you). The key difference between a mortgage and other loans is that if you stop making payments, the lender can take back the property through a process called foreclosure.

The property is the security the lender holds. This is why mortgage interest rates are usually lower than credit card rates or personal loans—the lender has less risk because they can recover their money by selling the house if you default. You own the home and live in it while you pay, but the lender holds a legal claim on it until the loan is fully repaid.

Key Takeaways

  • A mortgage is a long-term loan secured by the property itself, meaning the lender can foreclose if you stop paying.
  • Monthly payments cover both principal (what you borrowed) and interest (the lender's cost), plus sometimes property taxes and insurance.
  • The interest rate you receive depends on factors like your credit score, down payment size, loan term, and current market rates.
  • A down payment (typically 3 to 20 percent of the home price) reduces the amount you need to borrow and affects your monthly payment and interest rate.
  • Mortgages come in fixed-rate (payment stays the same) and adjustable-rate (payment can change) varieties, each with different risks and benefits.

How monthly payments are calculated

Your monthly mortgage payment is determined by four things: the loan amount, the interest rate, the loan term (how many years you have to repay), and sometimes additional costs. A 30-year mortgage at a lower interest rate will have smaller monthly payments than a 15-year mortgage at the same rate, because you are spreading the repayment over more months. A higher interest rate increases your payment, sometimes significantly.

Beyond the base loan payment, your monthly bill often includes property taxes (paid to your local government), homeowners insurance (required by the lender to protect the property), and sometimes PMI (private mortgage insurance, required if your down payment is less than 20 percent). These are often bundled into one payment called PITI (principal, interest, taxes, insurance). Ask your lender for a loan estimate before you commit—it shows the exact breakdown of what you will pay each month.

Down payment and what it means for your loan

A down payment is the money you contribute upfront toward the home purchase. The lender finances the rest. If a house costs $300,000 and you put down $60,000 (20 percent), the lender gives you a $240,000 mortgage. A larger down payment reduces the amount you borrow, which lowers your monthly payment and the total interest you pay over the life of the loan.

Down payment size also affects whether you must pay PMI. If you put down less than 20 percent, most lenders require PMI—an insurance policy that protects the lender if you default. PMI adds $100 to $300+ to your monthly payment depending on the loan size and your credit score. Once you have paid down the loan to 80 percent of the home's original value, you can usually request to have PMI removed, but you must ask—it does not happen automatically.

Fixed-rate versus adjustable-rate mortgages

A fixed-rate mortgage locks in the same interest rate for the entire loan term. Your monthly payment never changes (except for property taxes and insurance, which can increase). This makes budgeting predictable and protects you if interest rates rise. Most homebuyers choose fixed-rate mortgages for this stability.

An adjustable-rate mortgage (ARM) starts with a lower interest rate for a set period (often 3, 5, 7, or 10 years), then adjusts periodically based on market rates. After the initial period, your payment can increase significantly—sometimes hundreds of dollars per month. ARMs are riskier because you cannot predict future payments, but they can save money if you plan to sell or refinance before the rate adjusts. Only choose an ARM if you understand the adjustment schedule and can afford the payment at the highest likely rate.

Interest rates and what affects them

The interest rate you receive depends on several factors. Your credit score is the biggest one—borrowers with scores above 740 typically receive the lowest rates, while those below 620 pay significantly more or may not be approved at all. The loan-to-value ratio (how much you are borrowing compared to the home's value) also matters: a 20 percent down payment gets a better rate than a 3 percent down payment. The loan term affects it too—a 15-year mortgage usually has a lower rate than a 30-year one.

Broader market conditions also play a role. Interest rates rise and fall based on Federal Reserve policy, inflation, and economic conditions. You cannot control the market, but you can improve your credit score before explore, save a larger down payment, and shop around with multiple lenders—rates vary between them even on the same day. Getting pre-approved by several lenders before house hunting shows you what rate you actually may have access to for, not just what the advertised rate is.

The difference between pre-approval and pre-qualification

Pre-qualification is an informal estimate. You tell a lender basic information about your income and debts, and they give you a rough idea of how much you might borrow. It takes minutes and requires no documentation. Pre-qualification does not may provide anything and does not appear on your credit report.

Pre-approval is formal. The lender verifies your income, credit, employment, and assets by reviewing tax returns, pay stubs, and bank statements. They pull your actual credit report and run a background check. Pre-approval gives you a specific loan amount and rate (valid for 60 to 90 days) and shows sellers you are a serious buyer. It does result in a small, temporary dip in your credit score because the lender pulls your report, but this impact is minimal and recovers quickly.

What happens after you close on a mortgage

Once you sign the final paperwork and the lender funds the loan, you own the home and the mortgage begins. You make monthly payments to the lender (or to a loan servicer they hire to collect payments). Early in the loan, most of your payment goes toward interest; later, more goes toward principal. This is called amortization.

You can pay off a mortgage early by making extra principal payments or refinancing (taking out a new loan at a better rate to pay off the old one). Refinancing makes sense if rates drop significantly or your credit score improves, but it involves closing costs and resets the loan term, so do the math first. Some mortgages have prepayment penalties if you pay off early, though these are less common now. Always ask before signing.

Frequently Asked Questions

What is the difference between a mortgage and a home loan?

These terms are used interchangeably. A mortgage is a specific type of home loan where the property secures the debt. All mortgages are home loans, but not all home loans are mortgages (for example, a home equity line of credit is a home loan but not a mortgage in the traditional sense).

Can I get a mortgage with bad credit?

Yes, but it will cost more. Lenders with credit scores below 620 typically pay higher interest rates and may need a larger down payment. Some lenders specialize in lower-credit borrowers, but compare rates carefully—the difference can add tens of thousands of dollars over 30 years.

What does it mean to be underwater on a mortgage?

You are underwater when you owe more on the mortgage than the home is worth. This happens when home values drop after you buy. You can still live in the home and make payments normally, but you cannot sell without losing money, and refinancing becomes difficult.

How long does it take to close on a mortgage?

Closing typically takes 30 to 45 days from the time you make an offer. This includes the lender's appraisal, underwriting (verifying all your information), title search, and final walkthrough. Delays can happen if documents are missing or the appraisal comes in lower than expected.

What is mortgage insurance and do I always need it?

Mortgage insurance protects the lender if you default. You need it only if your down payment is less than 20 percent. Once you reach 20 percent equity in the home, you can request to have it removed, though you must ask your lender—it does not stop automatically.