The payment depends on your interest rate, loan term, and down payment

A $400,000 house does not have one mortgage payment. The monthly amount you owe depends on three things: how much you borrow, the interest rate you lock in, and how many years you take to repay it. On a $400,000 purchase price, if you put 20 percent down ($80,000), you borrow $320,000. At a 7 percent interest rate over 30 years, your principal and interest payment is roughly $2,130 per month. At 6 percent over the same term, it drops to about $1,920. At 5 percent, it falls to roughly $1,720. The difference between a 5 percent and 7 percent rate on this loan is $410 a month—nearly $5,000 a year.

Your actual monthly payment to the lender is usually higher than the principal and interest number, because most mortgages bundle in property taxes, homeowners insurance, and mortgage insurance (if you put down less than 20 percent). These costs vary sharply by location and by your specific situation. A house worth $400,000 in rural Iowa carries different property taxes than one in suburban Boston or coastal California. Your insurance premium depends on the home's age, condition, and location. If you borrow more than 80 percent of the purchase price, you also pay private mortgage insurance (PMI) until you reach 20 percent equity, which adds $200 to $400 or more per month depending on the loan size.

Key Takeaways

  • Principal and interest on a $320,000 loan (20 percent down on $400,000) ranges from roughly $1,720 to $2,130 per month depending on whether your rate is 5 percent or 7 percent over 30 years.
  • Your full monthly payment to the lender includes property taxes, homeowners insurance, and possibly mortgage insurance, which can add $400 to $1,000 or more depending on your location and down payment.
  • A smaller down payment lowers your upfront cash but raises your monthly payment because you borrow more and pay mortgage insurance.
  • The interest rate you receive depends on market conditions, your credit score, and the loan type you choose, and even a 1 percent difference changes your payment by several hundred dollars per month.

How the down payment changes what you borrow

The down payment is the cash you bring to closing. It reduces the amount you need to borrow. On a $400,000 purchase, a 20 percent down payment is $80,000, leaving a $320,000 loan. A 10 percent down payment is $40,000, leaving a $360,000 loan. A 5 percent down payment is $20,000, leaving a $380,000 loan. The larger the loan, the larger your monthly payment, even at the same interest rate.

Putting down less than 20 percent triggers mortgage insurance. On a $360,000 loan (10 percent down), PMI typically runs $150 to $300 per month. On a $380,000 loan (5 percent down), it can reach $300 to $500 per month. You pay PMI until you own 20 percent of the home's value, which takes years of payments. This is why a smaller down payment feels cheaper at first—you have less cash to bring—but costs more per month over time.

Interest rates move your payment up or down significantly

Interest rates change daily based on market conditions. They also vary by lender, by loan type (conventional, FHA, VA, USDA), and by your credit score. A borrower with a 750 credit score may receive a 6.2 percent rate while a borrower with a 650 score receives 7.1 percent on the same day from the same lender. Over 30 years on a $320,000 loan, that 0.9 percent difference amounts to roughly $200 per month.

The loan term also matters. A 15-year mortgage has a lower interest rate than a 30-year mortgage, but your monthly payment is much higher because you repay the loan in half the time. On a $320,000 loan at 6 percent, a 30-year term costs about $1,920 per month. A 15-year term at 5.5 percent costs about $3,100 per month. You pay less total interest over the life of the loan, but your monthly budget must absorb the higher payment.

Property taxes and insurance add to your monthly bill

Lenders require you to pay property taxes and homeowners insurance as part of your monthly mortgage payment. These go into an escrow account held by the lender, who pays the bills on your behalf when they come due. Property taxes vary enormously by location. In some counties, annual property tax on a $400,000 home is $3,000 to $4,000 per year (roughly $250 to $330 per month). In others, it is $8,000 to $12,000 per year (roughly $670 to $1,000 per month). Homeowners insurance typically runs $1,000 to $2,000 per year ($85 to $165 per month), though older homes or those in high-risk areas cost more.

These costs are not fixed. Property taxes increase when your county reassesses the home's value or raises the tax rate. Insurance premiums rise if claims increase in your area or if your home needs repairs. When you receive your mortgage statement, the "principal and interest" line is predictable, but the "taxes and insurance" line can shift year to year.

How to calculate your own payment

You can estimate your payment using an online mortgage calculator by entering the loan amount, interest rate, and loan term. Most calculators show principal and interest only. To get closer to your actual payment, add property taxes and insurance separately. Divide your annual property tax estimate by 12 and add it to the calculator result. Do the same for insurance. If you are putting down less than 20 percent, add the estimated PMI as well.

For a real number, you need a preapproval from a lender. A preapproval is a lender's estimate of how much you can borrow and at what rate, based on your credit, income, and debts. It includes the specific interest rate the lender will offer you, the exact loan term, and an estimate of property taxes and insurance for the home you are buying. This is the closest you can get to your actual payment before you close on the house.

What changes your payment after you close

Once you own the home, your principal and interest payment stays the same for the life of the loan (on a fixed-rate mortgage). Property taxes and insurance do not. Property taxes typically rise every few years as the county reassesses values or adjusts rates. Insurance premiums increase when you file a claim, when claims rise in your area, or when the insurer decides to raise rates. If you have PMI, it drops off automatically once you reach 20 percent equity, which lowers your payment.

If you refinance—taking out a new loan to replace your old one—your payment can change significantly. Refinancing makes sense when interest rates drop enough to offset the closing costs of a new loan, or when you want to change the loan term. Refinancing from a 30-year loan to a 15-year loan raises your monthly payment but cuts the total interest you pay.

Frequently Asked Questions

What is the monthly payment on a $400,000 house with no money down?

If you borrow the full $400,000 at 6 percent over 30 years, principal and interest is roughly $2,400 per month. You also pay mortgage insurance (typically $400 to $600 per month), property taxes, and homeowners insurance. Your total payment could easily exceed $4,000 per month depending on location. Most lenders require at least 3 to 5 percent down, and some loan programs do not allow zero-down purchases.

Does the payment change if interest rates drop after I close?

No, your payment stays the same if you have a fixed-rate mortgage. If you want a lower rate, you must refinance, which means explore for a new loan and paying closing costs again. Refinancing makes sense only if the new rate is low enough to save you money over time after you account for those costs.

How much of my payment goes to principal versus interest?

Early in the loan, most of your payment goes to interest. On a $320,000 loan at 6 percent over 30 years, your first payment includes roughly $1,600 in interest and $320 in principal. As you pay down the loan, the split shifts. By year 15, you are paying roughly $800 in interest and $1,120 in principal. By year 25, interest is down to $200 and principal is $1,720.

Can I lower my payment by extending the loan to 40 years?

Some lenders offer 40-year mortgages, which lower your monthly payment but increase the total interest you pay over the life of the loan. On a $320,000 loan at 6 percent, a 40-year term costs roughly $1,720 per month compared to $1,920 for 30 years. You save $200 per month but pay tens of thousands more in total interest. This option is useful only if your budget is tight and you plan to refinance or sell before the loan matures.

What if property taxes or insurance spike after I buy?

Your escrow payment (the portion of your mortgage payment that covers taxes and insurance) adjusts when these costs change. If your property tax assessment increases or your insurance premium rises, your lender recalculates your escrow payment and your total monthly bill goes up. You receive notice of the change before it takes effect, usually giving you time to adjust your budget.