Buying a house on one income: how to qualify and stay safe

How lenders judge one income

A lender checks whether your income is stable and likely to continue, documents it with pay stubs, W-2s or tax returns, and compares it with your monthly debts. Nothing in Fannie Mae's or FHA's rules treats a single borrower differently from a couple. A steady salary from one job can be stronger than two irregular incomes.

How debt-to-income limits apply

The CFPB describes the debt-to-income ratio as all your monthly debt payments divided by your gross monthly income. Fannie Mae's Selling Guide sets its maximum total ratio at 36 percent for manually underwritten loans, up to 45 percent with credit score and reserve requirements met, and 50 percent for loans underwritten through Desktop Underwriter. Other programs set their own limits.

On one income, those percentages translate into smaller dollar amounts, so each existing debt has a bigger effect.

Why reserves matter more

With two incomes, a job loss or illness often leaves one paycheck. With one income, it can leave none. That is why savings deserve extra weight:

• Lender reserves. Some loans require money left over after closing, measured in months of housing payments.
• Your own emergency fund. Separate from the down payment and closing costs, sized for your job security and health.
• Repair money. The first year of ownership often brings surprises. The first-year homeowner checklist covers what to expect.

A lower price that leaves several months of savings can be safer than a higher price that drains your account at closing.

Ways to make one income go further

Use assistance. Many state housing finance agencies offer down payment help or lower-cost loans for first-time buyers, often with income limits that a single earner may meet.

Consider loan programs with lower costs. FHA, VA, USDA and low-down-payment conventional programs each have different upfront and monthly costs. Compare them side by side.

Lower monthly debts. Paying off a small debt can have a larger effect on your ratio than a raise.

Look at the full cost. Taxes, insurance and HOA dues vary widely by property. Two homes with the same price can have very different payments.

Talk to a counselor. HUD-approved housing counselors can review your budget for free or at low cost.

Adding a co-borrower

A parent, partner or friend can sometimes join the loan as a co-borrower, adding their income. They also take on full responsibility for the debt, and it shows on their credit. Program rules differ on who can be a co-borrower and whether they must live in the home. Treat it as a serious long-term commitment for everyone.

The bottom line

One income can qualify for a mortgage if it is stable and your debts fit the program's ratio limits. Run your ratios, reduce small debts, look at assistance, and keep more savings than the minimum. The goal is a payment you can keep making even in a hard month.