How a Lender Sizes a Conventional Loan on a Low Down Payment

The Quick Read: A lender sizes your loan by taking the lower of the purchase price or the appraised value, then applying the maximum loan-to-value (LTV) ratio your program allows. Loan-to-value is the loan amount divided by that value. On a one-unit home you will live in, that maximum can reach 97% with a first-time buyer and a fixed rate, and 95% otherwise. Your income, credit, debts, and the county loan limit can then pull the number lower. All of this is subject to lender guidelines and full file review.

Key Terms Defined

• LTV (loan-to-value): The first mortgage divided by the home’s value. A 3% down payment means a 97% LTV.
• CLTV (combined LTV): All liens on the home added together, divided by value. A second loan counts here.
• DTI (debt-to-income ratio): Your monthly debts, including the new housing payment, divided by your gross monthly income.
• AUS (automated underwriting system): The software that reviews your file and issues a finding, which drives most conventional approvals.
• Conforming loan limit: The county-based ceiling on loans that Fannie Mae and Freddie Mac can buy.
• Mortgage insurance: Coverage that protects the lender, not you, when the down payment is under 20%. Each figure is subject to lender guidelines and a complete review of property type, leverage, and credit.

What Are You Really Solving For?

You are solving for the smallest cash outlay that a lender will approve. The loan amount is not a number you pick. It falls out of several tests, and the strictest test wins.

Across the wholesale programs Lendmire places files with, those tests come down to four. First, value: the lower of price or appraisal. Second, the leverage cap for your program and property. Third, the loan limit for your county. Fourth, your debt ratio and credit.

Lendmire is a mortgage broker, not a lender. It arranges conventional loan programs through wholesale lenders, and those lenders make the final call.

How Does the Lender Get From Price to Loan Amount?

The lender works through a fixed sequence. Here it is step by step, with what can change each step.

1. Find the value. The lender uses the lower of the sales price or the appraised value. Fannie Mae’s Selling Guide describes this as the standard calculation. What changes it: a low appraisal.

2. Pick the program lane. A first-time buyer with a fixed rate on a one-unit home can reach 97%. Other buyers on a principal residence reach 95%. What changes it: first-time status, unit count, occupancy.

3. Apply the maximum LTV. Multiply the value by the cap. That is the ceiling on the first loan. What changes it: a second lien, which brings CLTV into play.

4. Check the loan limit. The result must fit the conforming limit for your county. Ask your loan officer for the current figure, since it varies by county and unit count.

5. Run automated underwriting. The AUS reviews credit, debts, income, and assets. Its finding governs most files, with a total ratio ceiling of 50%.

6. Set the final loan. The smallest result from steps 1 through 5 becomes your loan. Your down payment is the price minus that loan, and cash to close adds closing costs on top.

Fannie Mae’s Eligibility Matrix is the master table behind these caps. It also states that when LTV, CLTV, and HCLTV (which counts undrawn home-equity lines) are all checked, the highest ratio governs.

What Leverage Does Each Situation Allow?

The cap depends on the loan’s purpose, the property, and who is buying. Occupancy decides the leverage. A second home tops out at 90%, and an investment property at 85% on one unit. That is all this article says about those, because the rest is about the home you live in.

Two details matter here. The 97% lane is fixed-rate only. Fannie Mae’s purchase guidelines bar adjustable-rate and high-balance loans from the 95.01–97% band. And a “first-time buyer” means no ownership interest in a home during the previous three years. A co-borrower who owns property can change that status.

Worked Examples Without the Dollar Signs

Think in percentages of price. That keeps the logic clear.

Case 1: The appraisal matches the price. Say a first-time buyer is paying 100% of price and the appraisal agrees. With a fixed rate on a one-unit home, the cap is 97%. The down payment is 3% of price. The sizing is simple.

Case 2: The appraisal comes in low. Now the appraisal lands below the price. The lender applies the cap to the lower figure. Your loan shrinks, and the gap between loan and price is yours to cover. The seller may lower the price, or you may bring more cash. A low appraisal hits low-down-payment buyers hardest, because they have the least cash cushion.

Case 3: Debt ratio is the limit. Suppose the home price fits the 97% cap, but the AUS finding balks at your total debts. The program is not the problem. Your DTI is. A lender may suggest paying down a card, adding a co-borrower, or choosing a lower price. This is where file review beats any rule of thumb.

Case 4: The price sits near the county limit. Here the loan limit, not LTV, may bind. A large down payment brings the loan under the ceiling. A small one may not.

Which Limit Binds First?

If your approved amount is lower than the LTV math suggests, ask which of the other two is the cause. Your loan officer can tell you from the AUS findings.

How Does Mortgage Insurance Change the Picture?

Mortgage insurance is required on a conventional loan above 80% LTV. Freddie Mac’s Guide states the same rule for the loans it buys. That makes it a monthly line item for almost every low-down-payment buyer. Leverage, reserves, and pricing vary by lender and program; the final terms follow the full file review.

It also feeds back into your qualifying. A smaller down payment raises LTV. A higher LTV raises the required coverage, since Fannie Mae’s requirements step up as LTV climbs. That lifts your monthly housing cost, which raises DTI, which can lower the loan the AUS will approve. It is a loop, and it is why a few extra points of down payment can matter more than they look.

Published typical annual premiums run 0.58% to 1.86% of the balance. That is a range, not a quote. Your actual cost depends on your file.

When Does Mortgage Insurance End?

Conventional mortgage insurance does not last forever, which is a common point of confusion for buyers who assume it stays for the life of the loan. Under the Homeowners Protection Act, you may request cancellation at 80% of the original value if your payment history is good, there are no subordinate liens, and the home has not declined in value. The servicer must end it automatically at 78%, if you are current. The CFPB explains both thresholds, including a midpoint-of-the-loan backstop.

The clock runs from the original value. A higher appraisal later does not change when you hit 78% on schedule.

Where the General Rule Breaks

The tidy sequence has edge cases.

• HomeReady versus standard 97%. Fannie Mae’s FAQ says HomeReady has no first-time-buyer requirement but carries an income limit of 80% of area median income. The standard 97% option needs a first-time buyer but has no program income limit.
• Two- to four-unit homes. The cap is 95%, not 97%. Under HomeReady, these homes call for a 3% contribution from your own funds, unless a grant is involved.
• Down payment source. On a one-unit HomeReady purchase, gifts, grants, and Community Seconds can cover the down payment. Your own savings are not always required.
• Community Seconds. When the second lien is an eligible Community Seconds loan, combined LTV can reach 105%.
• Manufactured homes. A one-unit manufactured home that is not the MH Advantage type is capped at 95%.
• Manual underwriting. Some files are reviewed by hand. The maximum leverage drops, and ratios tighten to 36% or 45%, subject to the reserve and score factors in the Eligibility Matrix.
• Education. First-time buyers above 95% LTV typically complete homeownership education.

What Do Credit and Debt Do to the Number?

The wholesale conventional programs we place files with start at a 620 decision score. The AUS finding governs most files, with a total ratio ceiling of 50%. An older federal rule capped DTI at 43% for qualified mortgages. That flat cap was replaced, and today’s limits come from the AUS finding and the matrix.

Credit events carry waiting periods set by the agencies: four years from a chapter 7 discharge, seven from a foreclosure, and four from a short sale or deed-in-lieu. Documented extenuating circumstances can shorten them.

Here is a practical call. If your score sits near the floor, a lender’s own overlays may set a higher bar than the agencies do. Ask early.

What Should You Bring to the Lender?

A short checklist keeps the sizing honest:

• The purchase contract, so the lender knows the price.
• Two forms of ID and your income documents.
• Bank statements and the source of your down payment, including gift letters.
• A list of monthly debts.
• A question for your loan officer: which limit binds on my file?

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. Reach the team at 828-256-2183.

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

About Lendmire

Lendmire is a mortgage brokerage (NMLS# 2371349) licensed for consumer mortgage lending in 16 states, arranging FHA, VA, conventional and jumbo purchase and refinance loans through a wholesale lending network. Eligibility is determined by the lender on each file. Scotsman Guide named Lendmire a Top Mortgage Workplace in both 2025 and 2026.

References

1. Fannie Mae Selling Guide B7-1-01, Provision of Mortgage Insurance

2. Fannie Mae Eligibility Matrix

3. Fannie Mae Selling Guide B2-1.3-01, Purchase Transactions

4. Freddie Mac Guide §4701.1

5. CFPB: When Can I Remove Private Mortgage Insurance PMI from My Loan

6. Fannie Mae FAQs: 97% LTV Options