A mortgage is a loan used to buy a home or other property, and it is secured by the property itself. That security is the defining feature: because the home backs the loan, the lender can foreclose and take it if you stop paying. In exchange for that lower risk, mortgages typically carry far lower interest rates than unsecured borrowing, and they are repaid over long terms that make a large purchase manageable.
How a mortgage works
You make a down payment upfront and borrow the rest. The lender disburses the funds to the seller, and you repay the loan in monthly installments over the term, commonly 15 or 30 years. Each payment chips away at the balance until the loan is gone and you own the home outright.
Most monthly mortgage payments bundle four things together, often abbreviated PITI.
| Part |
What it covers |
| Principal |
Repaying the amount borrowed |
| Interest |
The cost of the loan |
| Taxes |
Property taxes, often collected in escrow |
| Insurance |
Homeowners insurance, and mortgage insurance if applicable |
In the early years, more of each payment goes to interest; over time the balance shifts toward principal. This process is called amortization.
Fixed vs variable rates
Mortgages come with either a fixed or a variable interest rate, and the choice affects your risk.
- Fixed rate stays the same for the entire term. Your principal-and-interest payment is predictable, which many borrowers value.
- Variable rate, sometimes called an adjustable-rate mortgage, starts with an initial period and can then move up or down with market rates. It may begin lower but carries the risk of rising payments later.
Which fits depends on how long you plan to stay, your tolerance for payment changes, and where rates sit, a trade-off covered in depth in fixed vs variable mortgage. This is general information rather than advice for your circumstances, so verify current rate ranges and run the numbers for your own situation, since rates move with the broader environment.
The levers that shape the cost
A few choices drive what a mortgage costs overall:
- Down payment. A larger down payment means borrowing less and may help you avoid mortgage insurance.
- Term length. A 15-year loan has higher monthly payments but much less total interest than a 30-year loan.
- Interest rate. Even a small rate difference is significant over decades, so shopping multiple lenders matters.
- Fees and points. Closing costs and optional points to lower the rate affect the real cost. Compare the APR.
What to skip
- Borrowing the maximum a lender approves. The approval ceiling is not the same as a comfortable payment; leave room for the rest of your life.
- Ignoring taxes and insurance when budgeting. The full PITI payment, not just principal and interest, is what you actually pay.
- Skipping the comparison shop. Rates and fees vary between lenders, and the difference compounds over the life of the loan.
FAQ
What is the difference between a 15-year and 30-year mortgage?
A 15-year loan has higher monthly payments but lower total interest, while a 30-year loan lowers the monthly payment and raises the total interest paid. The right one depends on your budget and goals.
How much down payment do I need?
It varies by loan type. Larger down payments reduce the amount borrowed and can help avoid mortgage insurance, but the minimum differs by program. Verify the options available to you.
What is mortgage insurance?
It is insurance that protects the lender, often required when the down payment is below a certain threshold. It can sometimes be removed once you build enough equity.
Can I pay off a mortgage early?
Often yes, and extra payments reduce total interest. Check for any prepayment penalty in your specific loan terms first.
Where to go next
Fixed vs variable mortgage in 2026, renting vs owning in 2026, and how to save money for a house in 2026.