Conventional Loan Credit Requirements for a First-Time Buyer

The Quick Read: Conventional loan credit requirements come from three layers: agency rules, the automated underwriting system, and the lender’s own overlays. Across the wholesale programs Lendmire places files with, the starting point is a 620 decision score, and the automated finding governs most files. A first-time buyer can go up to 97% LTV (3% down) on a one-unit home. Score alone never settles it, because the full file gets reviewed.

What Do “Credit Requirements” Actually Mean?

They are not one number. Three layers stack on top of each other, and you have to clear all three.

The first layer is the agency rulebook. Fannie Mae and Freddie Mac set the baseline for loans they buy. The second layer is the automated underwriting system, which scores the whole file. The third layer is the lender, who can set tighter rules than the agencies do.

That third layer explains why two buyers with the same score get different answers at different lenders. It also explains why “conventional needs a 620” is only partly true now. Fannie Mae removed its fixed 620 minimum for Desktop Underwriter casefiles and lets the system weigh the full risk picture instead. Lenders still pull scores on every borrower. Many still hold their own floors.

Here is how it plays out on the wholesale programs Lendmire works with. The conventional lanes start at a 620 decision score. An adjustable rate under manual underwriting starts at 640. Those figures are subject to lender guidelines and full file review.

How Is a Conventional Loan Underwritten, Step by Step?

The lender pulls your credit, picks one representative score, runs the file through an automated system, then checks your debts against your income. Each step can change the outcome, and a late surprise can undo an earlier green light.

1. Application and credit pull. The lender orders a merged report from all three bureaus and requests scores for every borrower. This is a hard inquiry.

2. Representative score. One score stands in for each borrower. For most single-borrower files that is the middle of three scores. Joint applicants add a wrinkle, so ask your loan officer how the file is scored.

3. Automated finding. Fannie Mae’s Desktop Underwriter and Freddie Mac’s Loan Product Advisor weigh credit history, debt load, savings, down payment and other loan traits together. No single cutoff drives the answer.

4. Debt-to-income check. Your new housing payment is added to your other monthly debts and measured against gross income.

5. Documents. Income, assets and employment get verified against what the system asked for.

6. Appraisal and property review. The home has to support the loan.

7. Education, when required. Some low-down-payment first-time buyer files need a homeownership course.

Step four deserves a closer look. Debt-to-income, or DTI, is your monthly debt payments divided by your gross monthly income. On the wholesale conventional programs, the total ratio ceiling is 50% when the automated finding allows it. Manually underwritten loans run 36% or 45%, depending on the score and reserve factors in the Eligibility Matrix. Fannie Mae’s debt-to-income rules also say a loan fails if the ratio recalculated before closing climbs past those limits.

Read that last point twice. A new car loan between approval and closing can change your answer.

Which Credit Score Does the Lender Actually Use?

The lender uses a mortgage-specific score pulled from the bureaus, and it may not match the number in your banking app. Free apps often show a different scoring model. A gap of a few points, or more, is normal.

The set of approved models is also shifting. The Federal Housing Finance Agency is directing Fannie Mae and Freddie Mac to let lenders choose, on an interim basis, between Classic FICO and VantageScore 4.0. The rollout is staged. Which model your lender uses varies by lender, so ask early.

(Asking costs nothing, and it keeps you from comparing apples to a different fruit.)

What Does a First-Time Buyer Need Beyond the Score?

A first-time buyer here means someone with no ownership interest in a residence in the previous three years. That definition is what opens the 97% LTV door on a one-unit principal residence with a fixed rate. Without it, standard purchase leverage tops out at 95% LTV, or 5% down. Terms depend on the lender’s guidelines, the property type, the leverage, and a full review of the credit profile.

Here is how the leverage lines up by occupancy, per the wholesale programs:

Occupancy decides the leverage, so a home you live in gets the best terms.

Credit and leverage work together. The higher the LTV, the more the lender leans on your credit profile. A thin file at 97% LTV gets more scrutiny than the same file at 80%. The exact numbers vary by lender and program and follow a full review of property, leverage, and credit.

Then there is mortgage insurance. It is required above 80% LTV. You can request cancellation at 80% of the original value, with a good payment history, no second liens and no drop in value. The servicer must end it automatically at 78%. Published typical annual premiums run from 0.58% to 1.86% of the balance. That is a range, not a quote. Your credit score and LTV decide where you land in it. Final terms depend on the lender’s guidelines, the property type, and the borrower’s complete credit picture.

Where the General Rule Breaks

Several edge cases bend the usual rules. Here are the ones first-time buyers hit most.

Income-limited programs. HomeReady and Home Possible carry an income limit of 80% of area median income. They are not first-time-buyer-only, though. Fannie Mae’s HomeReady page says you do not need to be a first-time buyer, and it caps DTI at 50% on a principal residence. For buyers with moderate income and a small down payment, these lanes can be worth a look.

Homeownership education. Fannie Mae requires a course on certain first-time purchases, including HomeReady and loans above 95% LTV where all borrowers are first-time buyers. Fannie Mae’s guide allows any qualified provider aligned with national or HUD standards. Counseling finished before closing counts too. Each figure is subject to lender guidelines and a complete review of property type, leverage, and credit.

Thin or no credit file. Fannie Mae’s system now flags files where the lender must build a nontraditional credit history. Manual underwriting may apply, often with a lower maximum DTI. Freddie Mac handles no-score borrowers differently, so this is a lender-by-lender conversation.

Past credit events. The agencies set waiting periods:

Shorter periods can apply with documented extenuating circumstances. These are the agencies’ rules, and the lender still reviews the whole file.

Higher-balance loans. Above the conforming limit, jumbo lanes take over. On the wholesale side those start at a 660 decision score, with a 50% ratio ceiling on the fixed lanes.

Same Score, Different Outcomes

Score is only one input. Consider three first-time buyers who all show a middle score in the high 600s. Their files read very differently.

Buyer one has long-standing accounts, low card balances and a 3% down payment. Her DTI sits well below the ceiling. The automated system looks kindly on that mix. Leverage, reserves, and pricing vary by lender and program; the final terms follow the full file review.

Buyer two has the same score but also a new auto loan, taken two weeks before applying. His DTI climbs toward the limit. The system may still approve him, or it may not. Either way, he has less room.

Buyer three has the same score, a thin history and little savings behind a 3% down payment. Manual underwriting is more likely, and that route has tighter limits. Terms vary by lender guidelines, property type, leverage, credit profile, and full file review.

Three borrowers, one score. Three different decisions. That is why meeting a minimum is never the same as approval.

What Should You Do Before You Apply?

Protect your file, and do not open anything new. A short checklist beats a long wish list.

• Six months out: Pull your credit reports and dispute errors. Pay down card balances. Keep every account current.
• Three months out: Keep old accounts open. Hold off on financing furniture, cars or anything else.
• Thirty days out: Do not move money around without a paper trail. Do not change jobs without talking to your loan officer.
• Until closing: Treat your credit like glass. A late-added debt can trigger a re-review.

If you are close but not there, you have three options. You can wait and improve the score. You can add a co-borrower with stronger credit. Or you can compare other loan types. A broker can walk you through which one fits, since Lendmire arranges FHA, VA, conventional and jumbo loans through wholesale lenders across 16 states.

Key Terms Defined

Decision score: The credit score the lender uses to decide eligibility on a file.

DTI (debt-to-income ratio): Your monthly debts, including the new housing payment, divided by your gross monthly income.

LTV (loan-to-value): The loan amount as a percentage of the home’s value. A 97% LTV means 3% down. Exact terms depend on the lender’s guidelines, property type, leverage, and a full review of the borrower’s file.

Mortgage insurance: Coverage that protects the lender when you put down less than 20%. It cancels at 80% on request and ends at 78%.

Overlay: A lender rule that is stricter than the agency minimum.

Manual underwriting: A person-driven review used when the automated system can’t give an approval, with fixed limits on score, reserves and DTI.

If you are buying a home and want to see whether a conventional loan fits your file, Lendmire can help you compare the options and what each one asks of the file. You can start by reviewing Lendmire’s conventional loan programs.

For your own numbers, request a scenario review with Lendmire.

About Lendmire

Lendmire (NMLS# 2371349) is a mortgage broker licensed for consumer lending in 16 states. Lendmire arranges FHA, VA, conventional and jumbo purchase and refinance loans through wholesale lenders; every file is underwritten by the lender under the applicable program guidelines. Scotsman Guide named Lendmire a Top Mortgage Workplace in both 2025 and 2026.

References

1. Fannie Mae SEL-2025-09

2. Fannie Mae Selling Guide B3-6-02, Debt-to-Income Ratios

3. FHFA Credit Scores

4. Fannie Mae HomeReady

5. Fannie Mae Selling Guide B2-2-06, Homeownership Education