Mortgage Basics: How Home Loans Work
Understand how mortgages work: principal, interest, APR, loan types, terms, points, mortgage insurance, and escrow, explained simply.
A mortgage is a loan secured by real estate. You borrow money to buy a home, and the home serves as collateral: if you stop making payments, the lender can eventually foreclose. Understanding a few core concepts makes it much easier to compare offers and choose the right loan.
The parts of a mortgage payment
- Principal: the amount you borrowed. Each payment reduces it.
- Interest: what the lender charges to lend you the money. Early in a loan, most of each payment goes to interest; later, most goes to principal. This schedule is called amortization.
- Taxes and insurance: property taxes and homeowners insurance are often collected monthly into an escrow account, and the servicer pays the bills for you.
- Mortgage insurance: required for most conventional loans with less than 20% down (PMI) and for FHA loans (MIP). It protects the lender, not you.
Interest rate vs. APR
The interest rate determines your monthly principal-and-interest payment. The annual percentage rate (APR) includes the interest rate plus certain lender fees and points, expressed as a yearly rate. APR is useful for comparing the true cost of loans from different lenders, but remember that it assumes you keep the loan for its full term.
Fixed-rate vs. adjustable-rate
A fixed-rate mortgage keeps the same interest rate for the life of the loan, so principal and interest never change. An adjustable-rate mortgage (ARM) has an initial fixed period (for example, five or seven years) and then adjusts periodically based on an index plus a margin, within caps. See our full comparison: fixed vs. adjustable-rate mortgages.
Loan terms
The 30-year fixed is the most common U.S. mortgage because it keeps payments lower. A 15-year loan has higher monthly payments but usually a lower rate and dramatically less total interest. You can also pay extra principal on a 30-year loan to shorten it while keeping the flexibility of the lower required payment, as long as your loan has no prepayment penalty.
Major loan types
- Conventional: not government-insured; most follow Fannie Mae and Freddie Mac guidelines. "Conforming" loans fall under the annual loan limit set by the Federal Housing Finance Agency; larger loans are "jumbo" loans with stricter requirements.
- FHA: government-insured, lower credit and down payment requirements.
- VA: guaranteed by the Department of Veterans Affairs for eligible service members and veterans.
- USDA: backed by the U.S. Department of Agriculture for eligible rural and suburban areas.
Points and lender credits
Discount points are upfront fees paid to lower your interest rate; one point equals 1% of the loan amount. Whether points pay off depends on how long you keep the loan. Divide the cost of the points by the monthly savings to find your break-even month. Lender credits work in reverse: you accept a slightly higher rate in exchange for the lender covering some closing costs.
Rate locks
Rates move daily. Once you have an accepted offer, you can lock your rate for a set period, commonly 30 to 60 days. If closing is delayed past the lock, extensions may cost money, so ask about fees in advance.
What lenders look at
Underwriters evaluate the "three Cs": credit (your score and history), capacity (income and debt-to-income ratio), and collateral (the home's appraised value and your down payment). Stable employment history, documented income, and cash reserves all help.
Paying off your mortgage early
Extra principal payments reduce total interest and build equity faster. Common strategies include one extra payment per year, biweekly payments, or rounding up each payment. Before prioritizing this, make sure you have an emergency fund and are not carrying higher-interest debt.
This article is for general educational purposes and is not financial, legal, or tax advice. See our disclaimer.