The monthly payment on a $300,000 house ranges from roughly $1,430 to $2,150, depending on your interest rate, loan term, and down payment size.

The exact number depends on three things: how much you borrow, what interest rate you lock in, and whether you choose a 15-year or 30-year loan. A $300,000 purchase price does not mean a $300,000 loan — if you put down 20 percent, you borrow $240,000 instead. Interest rates vary by lender, your credit score, and market conditions on the day you close. A 30-year loan at 6.5 percent costs less per month than a 15-year loan at the same rate, but you pay far more interest over time.

The payment itself covers only principal and interest. You will also owe property taxes, homeowners insurance, and possibly mortgage insurance (PMI) if your down payment is less than 20 percent. These add $300 to $800 or more to your monthly housing cost, depending on your location and loan size.

Key Takeaways

  • A $300,000 house with 20 percent down ($60,000) and a 6.5 percent interest rate costs about $1,520 per month in principal and interest on a 30-year loan.
  • The same loan at 7.5 percent interest costs roughly $1,680 per month — a $160 difference that compounds over 30 years into tens of thousands of dollars.
  • Putting down less than 20 percent triggers mortgage insurance (PMI), which typically runs 0.5 to 1.5 percent of your loan amount annually and adds $100 to $300 per month.
  • Your total monthly housing payment includes taxes, insurance, and possibly PMI on top of the principal and interest figure — often 30 to 50 percent higher than the base mortgage payment alone.

How down payment size changes your monthly payment

The larger your down payment, the smaller the loan you need and the lower your monthly payment. A 20 percent down payment on a $300,000 house means borrowing $240,000. A 10 percent down payment means borrowing $270,000 — a $30,000 difference that translates to roughly $190 more per month at 6.5 percent interest over 30 years.

Down payments smaller than 20 percent trigger private mortgage insurance (PMI). This is not optional — lenders require it to protect themselves if you default. PMI typically costs between 0.5 and 1.5 percent of your loan amount each year, paid as part of your monthly mortgage payment. On a $270,000 loan, that is roughly $112 to $337 per month depending on your credit score and the lender's rules. PMI drops off automatically once you reach 20 percent equity in the home, but that can take years.

A 5 percent down payment ($15,000) on a $300,000 house means borrowing $285,000 and paying the highest PMI rate. A 3 percent down payment ($9,000) is available through some programs but also carries PMI. The trade-off is clear: you keep more cash in your pocket now, but your monthly payment climbs significantly.

Interest rate impact on your total cost

Interest rates move daily and vary by lender. A difference of just one percentage point changes your monthly payment by $200 or more and your total interest paid over 30 years by more than $70,000. At 5.5 percent on a $240,000 loan, your monthly principal and interest is roughly $1,363. At 7.5 percent on the same loan, it jumps to $1,680.

Your interest rate depends on your credit score, the size of your down payment, the loan term you choose, and current market rates. Borrowers with credit scores above 740 typically get the lowest rates. Those with scores below 620 may pay 1 to 2 percentage points higher. Shopping with multiple lenders can save you thousands — a 0.25 percent difference on a $240,000 loan costs you roughly $50 per month.

Locking in your rate before closing is crucial. Rates can shift between the time you make an offer and the time you close, sometimes weeks later. Most lenders let you lock a rate for 30 to 60 days, though longer locks may cost a small fee.

15-year versus 30-year loans

A 15-year mortgage has a higher monthly payment but costs far less in total interest. On a $240,000 loan at 6.5 percent, a 30-year payment is roughly $1,520 per month. A 15-year payment on the same loan at the same rate is about $1,980 per month — $460 more each month. Over 15 years, you pay roughly $117,000 in interest. Over 30 years, you pay roughly $307,000 in interest on the same $240,000 loan.

The 15-year loan makes sense if you can afford the higher payment and want to own your home free and clear faster. It also locks in your housing cost sooner — once the loan is paid off, you owe only taxes and insurance. The 30-year loan gives you lower monthly payments and more flexibility to save or invest elsewhere, but you pay substantially more in interest and carry the debt longer.

Some borrowers split the difference by taking a 30-year loan but making extra principal payments when they can. This reduces the total interest without locking you into a higher monthly obligation.

Property taxes, insurance, and other costs

Your mortgage payment covers only principal and interest. Your lender will require you to pay property taxes and homeowners insurance as part of your monthly payment, held in an escrow account. These costs vary dramatically by location. In some states, property taxes run 0.5 percent of home value annually; in others, they exceed 2 percent. On a $300,000 house, that is $1,500 to $6,000 per year, or $125 to $500 per month.

Homeowners insurance typically costs $800 to $1,500 per year depending on the home's age, location, and coverage level. That is roughly $65 to $125 per month. If you put down less than 20 percent, add PMI on top. Together, taxes, insurance, and PMI can easily add $400 to $800 to your monthly housing cost.

Some lenders also require you to pay homeowners association (HOA) fees if the property is in a planned community. These are separate from your mortgage payment and range from $100 to $500 or more per month depending on the community.

Using a mortgage calculator to estimate your payment

Online mortgage calculators let you plug in a loan amount, interest rate, and term to see your exact monthly payment. Most major lenders (Bank of America, Wells Fargo, Chase) and financial websites (Bankrate, NerdWallet, The Mortgage Professor) offer free calculators. Enter your down payment amount, the interest rate you expect to may have access to for, and whether you want a 15-year or 30-year loan.

The calculator shows your principal and interest payment. Add property taxes and insurance separately — your real estate agent or a local tax assessor can give you estimates for the specific house you are considering. If your down payment is less than 20 percent, ask the lender for a PMI estimate based on your credit score and loan amount.

Running the numbers with a few different interest rates and down payment amounts helps you understand what you can afford and what trade-offs make sense for your situation.

Frequently Asked Questions

What is the difference between principal and interest?

Principal is the amount you borrowed. Interest is what the lender charges you to borrow it. Each monthly payment covers both — early in the loan, most of your payment goes to interest; later, more goes to principal. Over 30 years, interest typically costs more than the original loan amount.

Can I pay off my mortgage early without a penalty?

Most mortgages have no prepayment penalty, so you can pay extra toward principal whenever you want. Paying an extra $100 or $200 per month shortens your loan term and saves thousands in interest. Check your loan documents or ask your lender to confirm there is no penalty.

What credit score do I need to get a mortgage?

Most conventional loans require a credit score of at least 620, though scores above 740 get the best rates. FHA loans (backed by the Federal Housing Administration) accept scores as low as 580. Your score affects not just whether you are approved, but what interest rate you receive.

Does my monthly payment include property taxes?

Yes, if your lender requires it. Most lenders hold property taxes and insurance in an escrow account and pay them on your behalf as part of your monthly payment. This ensures taxes and insurance stay current. Some lenders allow you to pay taxes and insurance separately, but this is less common.

What happens if interest rates drop after I lock in my rate?

You are locked into your rate and cannot change it without refinancing, which involves closing costs and a new application. Refinancing makes sense if rates drop significantly — typically 0.5 to 1 percent or more — and you plan to stay in the home long enough to recoup the closing costs.