How your credit score changes your mortgage cost, in dollars

On a $240,000 conventional loan, the difference between a 780 score and a 639 score in Fannie Mae’s current pricing grid is $5,700. You will never see that number printed on a Loan Estimate. It arrives folded into your interest rate, which is why two people buying identical houses on the same day can be quoted rates that differ by more than the market moved all month.

The mechanism has a name, the loan-level price adjustment, and Fannie Mae publishes the whole grid. Once you can read it, you can see exactly where your score sits, how far the next band is, and what crossing it is worth.

Where your score enters the price

Fannie Mae buys a large share of the conventional loans lenders make, and it charges the lender a one-time fee on each one based on risk. These fees are called loan-level price adjustments, or LLPAs. The biggest one comes from a grid that crosses your credit score with your loan-to-value ratio (the loan amount divided by the home’s value).

A few rules from the matrix itself shape everything else:

• Adjustments are percentages of the loan balance when Fannie buys the loan.
• They are cumulative. The score grid is one line item, and others stack on top for things like condos, cash-out refinances and second loans.
• Loans delivered with no credit score are charged at the lowest score band.
• Fannie collects the fee from the lender, by drafting the lender’s account or deducting it from the loan proceeds.

Since September 30, 2026, Fannie uses one grid for Classic FICO and VantageScore 4.0. FHFA says the agencies adjusted upfront fees that day to align them across the two models, so your lender’s choice of model no longer changes which table you’re priced on.

The 2026 grid at 20% down, priced out

Below is the 75.01% to 80% loan-to-value column of Fannie Mae’s purchase grid for loans longer than 15 years (matrix dated 09/30/2026). The dollar columns are a worked example, not a quote.

Example: a $300,000 home with 20% down. The loan is $240,000, which is exactly 80% loan-to-value.

The arithmetic is just the loan times the percentage: $240,000 x 0.0175 = $4,200 for the 680 to 699 band, for instance.

The steps between neighboring bands are uneven, and that matters more than the totals. Going from 719 to 720 saves $300 here. Going from 739 to 740 saves $900. The single biggest step in this column is 639 to 640, worth $1,200. If you’re a few points under one of the larger steps, that’s where effort before an application pays most clearly.

Why 5% down can carry a smaller adjustment

The grid isn’t a simple “more down payment, lower fee” ladder. Take the same $300,000 home with 5% down instead, a $285,000 loan at 95% loan-to-value:

At 680 to 699, the 95% loan carries $3,918.75 in adjustments against $4,200 for the smaller 80% loan. The usual explanation is that loans above 80% loan-to-value need private mortgage insurance, so the insurer absorbs part of the credit risk that Fannie would otherwise price. That doesn’t make low down payments cheaper overall. Mortgage insurance is its own monthly cost, and insurers generally price it by credit score too. All it shows is that you can’t compare score costs across down payments by looking at the LLPA alone.

How a fee becomes a rate

Very few borrowers write a check labeled “LLPA.” The lender pays Fannie and recovers the money from you in one of two ways.

The first is discount points, an upfront charge where each point costs 1% of the loan amount, per the CFPB. A 2.75% adjustment is the same size as 2.75 points. The second, and more common, is a higher interest rate. Lenders publish rate sheets that trade rate against upfront cost, and the CFPB’s own illustration shows the shape of it: on a $180,000 loan, paying $675 more at closing took the rate from 5.0% to 4.875% in its example. Run that in reverse and a cost the lender needs to recover becomes a slightly higher rate.

When the adjustment goes into the rate, you pay it every month for as long as you keep the loan. That’s why a score band can feel bigger than the one-time number suggests.

Two timing facts sit on top of this. The CFPB says mortgage rates “can change daily, sometimes hourly,” so the same score band can be priced differently on Tuesday than on Monday. And a rate lock protects you from market moves, but the CFPB lists your credit score among the changes that can still alter a locked rate. If your score drops after you lock, the band can change with it.

Which score puts you in a band

The grid uses your loan’s representative credit score. Fannie’s Selling Guide builds it in two steps: each borrower’s middle score (or the lower of two), then the lowest of those across everyone on the loan. A couple with middle scores of 761 and 698 is priced in the 680 to 699 row.

That has a practical edge. Sometimes the stronger borrower can qualify alone, and dropping the other borrower moves the loan into a cheaper band. Sometimes the lost income makes the loan unaffordable. The middle score rule walks through that trade-off, and our guide to the scores mortgage lenders actually pull explains why your app’s number is probably not the one in this table.

When the grid doesn’t apply to you

The same matrix lists loans where all LLPAs are waived, including HomeReady loans and loans to first-time homebuyers with qualifying income at or below 100% of area median income (120% in high-cost areas). Some Duty to Serve loans qualify too. If your income is anywhere near those limits, ask the lender to check, because a waiver erases every dollar in the tables above.

The grid is for conventional loans only. FHA and VA loans don’t use it, though lenders still price them by score on their own rate sheets, so a better score still helps there, just not through this table. Freddie Mac publishes its own credit fee schedule for the conventional loans it buys. We haven’t verified its current numbers, so don’t assume they match Fannie’s to the decimal. For how minimum scores differ from pricing, see credit score for a conventional loan.

Using the grid before you apply

1. Get your three mortgage scores, and your co-borrower’s, from a lender’s pull or a preapproval. Find each middle score and take the lower one.
2. Find your row in the table above and the next row up. Note how many points separate you from the line, and what crossing it is worth at your loan amount.
3. If you’re within reach of a big step, such as 639 to 640 or 739 to 740, give yourself time to work on it before the lender pulls credit. Getting mortgage-ready lays out a month-by-month plan.
4. Ask each lender for a quote at the same loan amount and down payment on the same day, since rates move daily. Keep shopping inside one window; the rate shopping guide explains how FICO groups those inquiries.
5. Ask whether you qualify for an LLPA waiver before comparing anything else.
6. Plug your own numbers into the score cost calculator to see the band-by-band difference at your loan size.