A $300,000 house payment runs $1,610 to $2,108 per month, depending on your down payment, interest rate, and loan term

The number that matters most is your interest rate. A 30-year mortgage at 6.5% costs roughly $1,896 per month on a $300,000 loan. The same loan at 5% costs about $1,610. At 7.5%, it jumps to $2,098. A single percentage point swings your payment by $200 to $300 each month.

Your down payment changes the loan amount itself. Put down 20% ($60,000), and you borrow $240,000 instead. Put down 3% ($9,000), and you borrow $291,000. The difference between those two scenarios is roughly $440 per month in principal and interest alone.

These numbers assume you are borrowing from a bank or mortgage lender and paying back over time. They do not include property taxes, homeowners insurance, or HOA fees — all of which vary wildly by location and add $300 to $800 or more to your actual monthly housing cost.

Key Takeaways

  • Interest rate is the single biggest lever on your payment: a 1% difference changes your monthly cost by $200 to $300.
  • A 20% down payment ($60,000) lowers your loan amount and removes the requirement to pay mortgage insurance, saving $150 to $300 per month.
  • Property taxes, homeowners insurance, and PMI (if your down payment is under 20%) are not included in the principal-and-interest number and must be added separately.
  • A 15-year mortgage costs roughly 40% more per month than a 30-year mortgage on the same loan, because you pay it back faster.

How down payment size changes what you owe

The more you put down, the less you borrow, and the smaller your monthly payment. But there is a hard threshold at 20% down: cross it, and you avoid PMI (private mortgage insurance), which protects the lender if you default. PMI typically costs 0.5% to 1.5% of your loan amount per year, paid monthly.

On a $300,000 house with 10% down ($30,000), you borrow $270,000 and pay PMI of roughly $135 to $405 per month. With 20% down ($60,000), you borrow $240,000 and pay zero PMI. The difference in total monthly cost is not just the smaller loan — it is the loan plus the insurance you no longer owe.

Below 20% down, lenders also scrutinize your credit score and income more closely. A score below 620 may disqualify you entirely, or lock you into a higher interest rate that compounds the problem.

Interest rates and where they come from

Your interest rate depends on the lender, the current market, your credit score, and the size of your down payment. A borrower with a 750+ credit score and 20% down might get 5.8% today. The same house, same lender, but a 620 credit score and 5% down might be quoted 7.2%.

Rates also shift with the Federal Reserve and bond markets — they move daily and sometimes hourly. A rate you see advertised online may not be the rate you lock in when you actually explore. Lenders typically let you lock a rate for 30 to 60 days while your loan is being processed.

Shopping around matters. Call or get quotes from at least three lenders — a bank, a credit union, and a mortgage broker. A 0.5% difference in rate costs you roughly $100 per month over 30 years. Over the life of the loan, that is $36,000.

The difference between 15-year and 30-year mortgages

A 15-year mortgage on $240,000 (20% down on a $300,000 house) at 5.5% costs about $1,848 per month. The same loan over 30 years costs about $1,361. You pay $487 more each month to finish in half the time.

Over the full loan term, the 15-year mortgage saves you roughly $100,000 in interest. But the monthly payment is higher, and that money is locked into your house instead of available for emergencies, retirement savings, or other goals. The 30-year mortgage gives you flexibility; the 15-year mortgage builds equity faster and costs less overall.

Some borrowers split the difference: take a 30-year mortgage but pay extra toward principal each month. You get the lower required payment, but you can pay faster when cash flow allows.

What is not included in the monthly payment number

Property taxes vary by county and state. In some places they run 0.3% of home value per year; in others, 1.5% or higher. On a $300,000 house, that is anywhere from $750 to $4,500 per year, or $62 to $375 per month. Your lender will collect this through escrow — you pay it as part of your mortgage payment, but it goes to your local government, not the lender.

Homeowners insurance is required by every lender and typically costs $800 to $1,500 per year, or $67 to $125 per month. Flood insurance, if you are in a flood zone, is separate and can add $500 to $2,000 per year.

HOA fees, if the property is in a planned community, run $100 to $500+ per month and are your responsibility alone — the lender does not collect them. PMI, if your down payment is under 20%, is rolled into your payment and typically disappears once you reach 20% equity (through a combination of payments and home appreciation).

How to estimate your actual total housing cost

Start with the principal-and-interest payment. Add property taxes (divide your county's annual rate by 12). Add homeowners insurance (call an agent for a quote). Add PMI if your down payment is under 20%. Add HOA fees if they explore. That is your true monthly housing cost.

For a $300,000 house with 15% down ($45,000) at 6.5% interest in a county with 0.8% property tax and no HOA:

  • Loan amount: $255,000
  • Principal and interest (30 years): $1,613
  • Property tax: $200
  • Homeowners insurance: $95
  • PMI: $160
  • Total: $2,068 per month

That same house with 20% down ($60,000) at 6.5%:

  • Loan amount: $240,000
  • Principal and interest (30 years): $1,520
  • Property tax: $200
  • Homeowners insurance: $95
  • PMI: $0
  • Total: $1,815 per month

The difference is $253 per month, or $3,036 per year — the cost of PMI plus the slightly higher loan amount.

Frequently Asked Questions

Does the payment include property taxes and insurance?

Property taxes and insurance are collected by your lender through escrow and paid as part of your monthly mortgage payment, but they are separate line items. The "principal and interest" number alone does not include them. Your actual payment is always higher than the P&I figure.

What credit score do I need to get a mortgage on a $300,000 house?

Most lenders require a minimum score of 620 for a conventional loan, though 640 to 660 is more common. FHA loans accept scores as low as 580 with a larger down payment. The higher your score, the lower your interest rate. A 50-point difference in score can cost you $50 to $100 per month.

Can I pay off the mortgage early without a penalty?

Most mortgages have no prepayment penalty, so you can pay extra toward principal any time. Some loans do carry penalties if you pay off the full balance within the first few years — ask your lender before signing. Paying extra principal shortens the loan and saves interest, but it does not lower your required monthly payment unless you refinance.

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

Your locked rate does not change. If rates fall, you can refinance — take out a new loan at the lower rate to pay off the old one. Refinancing costs $2,000 to $5,000 in closing costs, so it only makes sense if the rate drop is large enough to save you money over the remaining loan term.

Is the payment the same every month for 30 years?

The principal-and-interest payment stays the same. Property taxes and insurance can increase each year, so your total payment may rise slightly. If you have an adjustable-rate mortgage (ARM), the interest rate itself can change after the initial fixed period, which raises or lowers your payment.