What Mortgage Lenders Actually Look At Before Approving a Loan
Approval on a US mortgage usually comes down to five factors weighed together, not any single number in isolation.
There's no single magic number that gets a mortgage approved in the United States. Lenders weigh several factors together, and a weakness in one area can often be offset by strength in another. Understanding what's actually being evaluated helps you see your own application the way an underwriter does, rather than fixating on one number, like your credit score, that only tells part of the story.
1. Credit history
Your credit report shows how you've handled debt over time — on-time payments, any missed payments, how long you've had credit accounts open, and how much of your available credit you're using. Your credit score is a summary of this history, but underwriters often look at the underlying report too, not just the number. Most conventional loans want a score in the high 600s or above, while FHA loans can allow lower scores with a larger down payment.
2. Debt-to-income ratio
This is your total monthly debt payments, including the new mortgage payment, divided by your gross monthly income, and it's one of the most heavily weighted factors in US mortgage lending. Most lenders want this ratio under somewhere between 36% and 43%, though some loan programs allow higher ratios with compensating factors. You can check your own ratio with our debt-to-income calculator before you talk to anyone.
Why DTI matters more than people think
A high income doesn't protect you if your existing debt payments are also high. Lenders care about how much of your income is already spoken for, because that's what determines how much room you realistically have for a mortgage payment on top of everything else.
3. Income stability
Lenders generally want to see steady, verifiable income — typically at least two years in the same job or field. Self-employed applicants often face more scrutiny here, since income can vary year to year, and underwriters may average multiple years of tax returns rather than relying on a single strong year.
4. Down payment and loan-to-value ratio
The size of your down payment relative to the home's price sets your loan-to-value ratio, which affects both your rate and whether PMI applies. A larger down payment generally means a lower rate and no PMI once you cross 20% equity, while a smaller down payment, common with FHA and VA loans, opens the door to buying sooner but usually carries extra insurance costs.
5. The property itself
Unlike a personal loan, a mortgage is secured by the home, so lenders order an appraisal to confirm the property is worth at least what you're paying for it. If the appraisal comes in below the purchase price, it can affect how much the lender is willing to finance, regardless of how strong your personal financial profile is.
- Credit history and score
- Debt-to-income ratio
- Income stability and verification
- Down payment and loan-to-value ratio
- The appraised value of the property
Loan type changes the weighting
Conventional, FHA, VA and USDA loans each weigh these factors slightly differently. VA loans, for eligible veterans, can allow 0% down with no PMI. FHA loans allow lower credit scores and smaller down payments in exchange for mortgage insurance that typically lasts the life of the loan. We cover the differences in our comparison of mortgage types.
What you can actually influence
Some of these factors take years to shift, like length of credit history. Others can move in weeks, like paying down a credit card balance to lower your DTI or reduce your credit utilization. Our guide on improving your position before applying focuses specifically on the levers you can pull in a realistic timeframe.
How automated underwriting has changed the process
Many US mortgage lenders now run applications through automated underwriting systems before a human ever reviews the file. These systems weigh the same core factors — credit history, DTI, income stability, down payment and property value — but apply them consistently and quickly, often returning a preliminary decision within minutes. A human underwriter typically steps in only when the automated system flags something ambiguous, like a recent gap in employment or an unusual pattern of deposits.
Why the same applicant can get different answers from different lenders
Because each lender sets its own overlays and thresholds within these systems, two lenders reviewing an identical file can reach different conclusions. One lender might weight DTI more heavily and decline an application another lender approves by leaning more on a strong credit history. This is part of why comparing offers from more than one lender is worth the modest inconvenience — a decline from one lender says something about that lender's specific criteria, not necessarily about your overall financial position.
Compensating factors
Lenders often allow a weaker area to be offset by a compensating factor elsewhere in the file. A higher-than-typical DTI might be approved anyway if you have significant cash reserves, a long credit history, or a large down payment. Knowing this matters if you've been declined once — a different lender, or the same lender with additional context provided, may weigh your compensating factors differently.
How this differs for a co-borrower
Adding a co-borrower effectively blends two credit and income profiles into one file, which can help when one applicant's numbers alone wouldn't clear a lender's thresholds. It also means both parties are fully responsible for the mortgage, which is worth weighing carefully before treating a co-borrower as a simple workaround rather than a shared financial commitment.
Why declines aren't always about you
Lending criteria shift with the broader economy — during periods of tighter credit conditions, mortgage lenders across the US market can raise their thresholds broadly, meaning an application that would have cleared easily a year earlier might face more scrutiny now, independent of anything that changed in your own file.
How much a single late payment actually matters
A single late payment, especially an isolated one on an otherwise clean history, tends to matter less than people fear, particularly if it's several years old and was quickly corrected. Lenders generally weigh recent, repeated late payments far more heavily than a one-off years in the past.
The role of an existing banking relationship
Some lenders weigh an existing banking relationship — an established checking account, prior loans paid as agreed — as a soft compensating factor, even though it isn't one of the core five factors. This isn't decisive on its own, but it explains why a credit union or bank you already use might sometimes offer terms slightly different from a lender who has no prior history with you.
Bringing it back to your own application
Before you apply anywhere, it helps to write down, in plain terms, how you'd honestly rate yourself on each of the five factors above. That short exercise usually reveals which single factor is doing the most damage to your file, which is a far more useful place to spend your preparation time than guessing broadly at what might help.
What to do next
Run your own numbers through the debt-to-income calculator before you talk to a lender, so you know how an underwriter is likely to see your application before they do.
This content is general information, not personalized financial advice — your specific situation may differ.