What your lender will approve you for versus what you can actually pay

The amount of house you can afford depends on two separate numbers that often don't match: what a lender will approve you to borrow, and what you can actually pay each month without running short on other bills. A lender typically approves you for a mortgage if your monthly payment stays below 28% of your gross monthly income — that's income before taxes. But that approval doesn't mean you can comfortably afford the house. If you earn $5,000 a month before taxes, a lender might approve you for a $1,400 payment. After taxes, you might take home $3,500. That $1,400 payment is 40% of what you actually have to spend, which leaves little room for property taxes, insurance, maintenance, or emergencies.

Start by calculating what payment fits your actual take-home pay, not what a lender says you may have access to for. Then work backward to find the house price that matches that payment. This approach protects you from borrowing more than you can sustain.

Key Takeaways

  • Lenders approve mortgages based on gross income (before taxes), but you pay from take-home income (after taxes), which is typically 20 to 30% lower.
  • A safe monthly payment is usually 15 to 20% of your take-home pay, leaving room for property taxes, insurance, maintenance, and other expenses.
  • The relationship between monthly payment and house price depends on your interest rate, loan term, and down payment size — the same payment buys different prices under different conditions.
  • Property taxes, homeowners insurance, and maintenance costs add 25 to 50% to your base mortgage payment, so the total housing cost is always higher than the loan payment alone.
  • Your debt-to-income ratio — all monthly debt payments divided by gross income — affects both approval odds and the maximum payment a lender will allow.

How to calculate the payment you can actually afford

Start with your monthly take-home pay — the amount that actually hits your bank account after taxes, Social Security, and any other deductions. If you're unsure, look at a recent pay stub or bank statement. Multiply that number by 0.15 to find a conservative monthly housing payment target. If you take home $3,500 a month, a safe housing payment is around $525. If you take home $5,000, aim for roughly $750.

That $525 or $750 is your total housing payment, which includes the mortgage principal and interest, property taxes, homeowners insurance, and mortgage insurance if your down payment is less than 20%. It does not include maintenance, utilities, or HOA fees — those come from the rest of your budget. Once you know your target payment, you can use a mortgage payment calculator to find the loan amount and house price that produces that payment. The calculator will ask for your interest rate, loan term (usually 15 or 30 years), and down payment percentage. Plug in realistic numbers based on current rates and what you have saved.

How interest rates and loan terms change the price you can afford

The same monthly payment buys a different house price depending on your interest rate and how long you borrow the money. A $400 monthly payment on a 30-year loan at 6% interest covers a loan of roughly $74,000. The same $400 payment on a 15-year loan at 6% covers only about $42,000. The difference is that you're paying off the shorter loan faster, so less of each payment goes toward interest and more toward principal.

Interest rates have an even larger effect. A $400 monthly payment at 4% interest on a 30-year loan covers about $86,000. At 7% interest, the same payment covers only about $63,000. When rates are low, your payment stretches further. When rates are high, the same payment buys less house. This is why the timing of your purchase and your credit score — which affects the rate you're offered — matter so much. A 0.5% difference in rate can shift the affordable price by $15,000 to $25,000 on a typical mortgage.

The gap between your loan payment and your total housing cost

Your mortgage payment covers only the loan itself. Your total monthly housing cost is higher because it includes property taxes, homeowners insurance, and mortgage insurance (if your down payment is less than 20%). These three items typically add 25 to 50% to your base loan payment, depending on where you live and the size of your down payment.

Property taxes vary widely by location — from less than 0.5% of home value per year in some states to over 2% in others. A $300,000 house in a high-tax state might carry $500 a month in property taxes alone. Homeowners insurance typically runs $100 to $200 a month for a house in that price range, though it's higher in areas prone to hurricanes, earthquakes, or wildfires. Mortgage insurance (PMI) applies when your down payment is less than 20% and usually costs 0.5 to 1% of the loan amount per year, split into monthly payments. If you borrow $240,000 with 10% down, PMI might add $100 to $200 a month. None of these costs appear in the base mortgage payment, but they all come out of your monthly budget.

How your debt-to-income ratio limits what lenders will approve

Lenders use your debt-to-income ratio (DTI) to decide how much they'll lend you. This is the total of all your monthly debt payments — car loans, student loans, credit cards, child support, and the new mortgage — divided by your gross monthly income. Most lenders cap your DTI at 43%, though some go as high as 50% for borrowers with strong credit and savings.

If you earn $6,000 a month gross and already pay $800 a month toward a car loan and student loans, you have $5,200 left in your DTI budget. At a 43% cap, your total debt payments can't exceed $2,580. Subtract the $800 you already owe, and you have $1,780 available for a mortgage payment. That's what the lender will approve you for — but it may still be more than you can comfortably pay from your take-home income. The DTI limit protects lenders, not you. Your own budget should be stricter.

Why down payment size affects affordability

A larger down payment lowers your monthly payment in two ways: you borrow less money, and you avoid mortgage insurance. If you put 20% down, you don't pay PMI. If you put 10% down, you do. The difference is significant. On a $300,000 house, putting 10% down instead of 20% means borrowing an extra $30,000 and paying PMI on the full loan, which might add $150 to $250 a month to your payment.

This is why saving for a larger down payment directly increases the house price you can afford on the same monthly budget. If you can afford a $1,400 payment and you have $30,000 saved, you face a choice: put 10% down on a more expensive house, or put 20% down on a less expensive one and avoid PMI. The second option usually leaves you with a lower total payment and more financial cushion.

Adjusting your target when rates or income change

Interest rates and your income both shift over time. When rates drop, the same monthly payment can cover a higher loan amount, which means you could afford a more expensive house if you're shopping. When rates rise, your payment buys less. Similarly, if your income increases — through a raise, a second job, or a partner's income — you can afford a higher payment and a more expensive house. The reverse is true if your income drops or you take on new debt.

Use these changes as a signal to recalculate your affordable price. Don't assume the number you calculated six months ago is still accurate. Rates and your financial situation both change, and your target should move with them. If you're planning to buy within the next year, you might also consider locking in a rate through a rate lock agreement, though this typically costs money and only works if you're actively in the mortgage process.

Frequently Asked Questions

What if a lender approves me for more than I think I can afford?

Lenders approve based on debt-to-income ratio, not on your actual comfort or emergency fund. You can be approved for $500,000 and still not afford it if your take-home pay is tight. Use your own budget as the final check. If the payment would leave you with less than $500 a month after all bills, it's too high.

How do I know what interest rate to assume when calculating affordability?

Check current rates from at least three lenders — your bank, a mortgage broker, and an online lender. Rates change daily and vary slightly by lender. Use the current average rate, not the lowest advertised rate, because you may not may have access to for the absolute lowest. Add 0.25 to 0.5% to the current rate as a buffer in case rates rise before you close.

Should I use a 15-year or 30-year loan to calculate what I can afford?

Calculate both. A 30-year loan has a lower monthly payment, so it shows you the maximum house price you could afford. A 15-year loan has a higher payment but you build equity faster and pay less interest overall. Many people can afford the 30-year payment but choose the 15-year loan if they have stable income and want to pay off the house sooner.

Does my down payment size change how much house I can afford?

Yes. A larger down payment lowers your monthly payment because you borrow less and avoid mortgage insurance. If you have $60,000 saved, putting 20% down on a $300,000 house is different from putting 10% down on a $400,000 house, even though both use your savings. The first option has a lower payment and no PMI.

What if I have student loans or other debt — does that reduce what I can afford?

Yes. Your debt-to-income ratio includes all monthly debt payments, not just the mortgage. If you owe $300 a month on student loans and $200 on a car, those $500 count against your DTI limit. This leaves less room for a mortgage payment. Paying down other debt before buying increases the mortgage payment you can afford.