What percentage of my income should go to a mortgage?

Short answer: the traditional guideline is no more than 28 percent of your gross monthly income on housing costs, and no more than 36 percent on all debts combined. Many lenders allow higher ratios, but the guideline exists because it has worked — borrowers who stay near it historically manage their payments more comfortably.

For example, with a gross monthly income of $5,000, the 28 percent rule gives you a maximum monthly housing payment of $1,400. That housing payment includes principal, interest, property taxes, and homeowners insurance — often called PITI.

This is a US lending guideline, not a law, and rules vary by loan program and country. Treat it as a sanity check rather than a verdict.

The 28/36 rule, explained

The guideline most often cited is called the 28/36 rule. It has two halves. The front-end ratio says your housing costs — principal, interest, property taxes, insurance, and any HOA or condo fees — should not exceed 28 percent of your gross monthly income, meaning income before taxes.

The back-end ratio says your total monthly debt payments, including the housing costs plus car loans, student loans, credit card minimums, and child support, should not exceed 36 percent of gross income. This total is your debt-to-income ratio, or DTI.

Both halves matter. A housing payment at 28 percent is comfortable only if your other debts leave room inside the 36 percent ceiling. With the $5,000 monthly income example, total debt payments should stay under $1,800 — so a $1,400 mortgage payment works only if your other debts total $400 or less per month.

Why 28 percent became the number

The 28 percent cap did not come from nowhere. It is based on decades of lending data showing that borrowers who keep housing costs at or below this threshold are more likely to manage their mortgage payments while staying financially stable in other areas of life.

It reflects a simple truth about budgets: housing is usually the largest single expense, and when it grows too large, it squeezes everything else — savings, emergencies, retirement, and the ordinary texture of life. Being "house poor" is a real condition: you own a home but cannot afford much else, and the stress rarely feels worth it in hindsight.

Lenders adopted the rule because it helped them gauge whether borrowers could realistically repay. It remains the baseline that conventional conforming loan programs use to screen applicants.

What lenders actually allow

Here is where the honest picture gets more complicated. The 28/36 rule is a guideline, not a legal limit, and many lenders approve borrowers well above it.

Conventional loans can allow back-end DTI ratios up to 45 percent, and some approvals reach 50 percent through automated underwriting when compensating factors are present. FHA loans allow a 31 percent front-end and a 43 percent back-end ratio, stretching toward 50 percent on the back end with strong compensating factors like cash reserves. VA loans skip a fixed front-end cap entirely and use a 41 percent back-end guideline that flexes higher when residual income clears the benchmark.

Qualifying for a larger loan is not the same as affording it comfortably. Lenders decide what you can borrow; only you can decide what you can live with.

The income you should use

Always run the math on gross monthly income — your pay before taxes and deductions — because that is what the guidelines use. But also run it on your net income, your actual take-home pay, because that is what you live on.

Some advisers suggest a parallel rule of keeping housing costs around 25 percent of net monthly income. Comparing the two numbers gives you a more honest picture than either alone. If the gross-income math says a payment is fine but the net-income math says it will be tight, believe the second one.

And be careful about whose income you count. If you are buying with a partner, base the payment on income that is stable and likely to continue. One-time bonuses, overtime that may not repeat, and income that requires both partners working full time indefinitely all deserve a skeptical eye.

Costs beyond the mortgage payment

The 28 percent figure covers PITI plus HOA fees, but owning a home costs more than that. Utilities, maintenance, repairs, and home improvements sit outside the ratio entirely, yet they are real and recurring.

A widely used estimate is that maintenance and repairs run about 1 percent of the home's value per year, though older homes can cost more. On a $400,000 home, that is roughly $4,000 a year — over $300 a month — that the 28 percent rule never mentions.

This is why buying at the maximum you qualify for is risky. The mortgage is the floor of your housing costs, not the ceiling. Leave breathing room in your budget for the costs that do not show up in any ratio.

When going above 28 percent is reasonable. There are legitimate situations where stretching above the guideline makes sense. If you have high income with low fixed expenses elsewhere, a higher percentage may be genuinely affordable. If you are early in a career with strong income growth ahead, some stretch is rational — though it is still a bet on the future.

In very high-cost housing markets, the 28 percent rule can be nearly impossible for even solid earners to meet without buying far from work or waiting many more years. People in these markets routinely spend more, and many manage fine — but they should do it with eyes open, with an emergency fund, and without other heavy debts competing for the same dollars.

The key question is never "what does the rule allow" but "what happens if my income dips 20 percent?" If the honest answer is panic, the payment is too high regardless of what any ratio says.

How the payment is actually built. It helps to see what the monthly payment consists of, because each part can surprise you. Principal and interest are the loan itself — the part most calculators show. Property taxes are set by your local government and can rise over time even when your loan payment is fixed; in high-tax states they can add hundreds per month. Homeowners insurance protects the lender's collateral and yours, and premiums have been climbing in many regions.

If you put down less than 20 percent on a conventional loan, private mortgage insurance gets added until you build enough equity. HOA or condo fees, where they exist, are not part of the loan at all but are absolutely part of your monthly housing cost — and they tend to increase over time.

When you run affordability numbers, include every one of these. A payment that looks fine as principal and interest alone can look very different once taxes, insurance, and fees join it.

Renting versus buying at the margin

Sometimes the honest answer to "what percentage should go to a mortgage" is that renting remains the better deal for now. In markets where home prices are very high relative to rents, the monthly cost of owning — mortgage plus taxes, insurance, and maintenance — can far exceed the cost of renting a comparable place.

There is no shame in that math. Buying is not automatically smarter than renting; it depends on prices, rates, how long you will stay, and what else you would do with the money. A renter who invests the difference diligently can come out ahead of a stretched buyer, especially over shorter time horizons where transaction costs eat the gains.

The percentage guideline still applies as a ceiling when you do buy. But if meeting it requires buying a home that does not fit your life, waiting and renting well is a legitimate financial strategy, not a failure.

Stress-test with a real budget

Ratios are abstractions; a budget is concrete. Before committing to a payment, build a full monthly budget with the proposed housing cost in it — every line item, from groceries to retirement savings to the small pleasures that make life livable. Then live on that budget for two or three months while you are still renting, banking the difference between your rent and the proposed payment.

This exercise does two things. It proves whether the payment actually fits your life, not just your spreadsheet. And it builds your down payment or emergency fund in the process. If the trial months feel comfortable, you have your answer. If they feel like deprivation, you have a more honest answer than any ratio could give you.

Pay special attention to what gets squeezed first. If it is retirement savings or the emergency fund, the payment is too high no matter what the guidelines say. Those are not discretionary line items; they are the foundation the house payment stands on.

The calm bottom line

Aim for no more than 28 percent of gross income on housing and 36 percent on all debts combined. Know that lenders will let you go higher, and that their willingness is not advice. Run the numbers on your actual take-home pay, budget for maintenance on top of the mortgage, and stress-test the payment against a leaner income.

The best mortgage percentage is not a fixed number — it is the one that lets you pay the loan, keep saving, and still live your life. The rules point you in the right direction. Your own budget writes the final answer.