Mortgage rates are set in two layers. First, the market: most home loans are packaged into mortgage-backed securities, and what investors will pay for those securities, along with the lender's costs and the agencies' guarantee fees, sets each lender's daily rate sheet. Second, your file: credit score, down payment, loan type, occupancy, property type, loan amount and term move you to a particular spot on that sheet. The Federal Reserve influences the backdrop but doesn't set mortgage rates. This article explains the mechanics only. It doesn't quote rates, because a rate without your file, a property and a lock date isn't a real number.
Most lenders don't keep the loans they make. A conventional loan is usually sold to Fannie Mae or Freddie Mac, and in most cases the lender receives mortgage-backed securities in exchange. Fannie and Freddie guarantee investors the payment of principal and interest on those securities and charge a guarantee fee for it, which covers projected credit losses, administrative costs and a return on capital. Lenders typically pass that cost to borrowers through the rate (FHFA, guarantee fees).
So the price investors are willing to pay for mortgage securities on a given day is the starting point. When investors pay more for those securities, lenders can offer lower rates for the same points. When they pay less, rates for the same points go up.
Mortgage securities compete with other long-term investments, so they respond to the same forces: inflation expectations, economic data, the supply of mortgage bonds, and the yields on long-term Treasury securities. Mortgage pricing often moves in the same direction as longer-term Treasury yields, though not in lockstep. Lender rate sheets can change more than once in a day when the bond market moves.
The Federal Reserve's Federal Open Market Committee sets policy that alters the federal funds rate, the overnight rate banks charge each other. The Fed says changes in that rate set off a chain of events that affect other short-term rates, long-term rates and the broader economy (Federal Reserve, FOMC). But the Fed doesn't set mortgage rates. Markets often price in an expected Fed decision before it's announced, so mortgage pricing on announcement day can move up, down or not at all.
A lender's rate sheet isn't a single rate. It's a grid: each available note rate is paired with a price, shown as points you pay or credits you receive. A lower rate costs more upfront. A higher rate can come with a credit that pays some closing costs. The CFPB explains it the same way: discount points lower your rate in exchange for an upfront fee, and lender credits lower your closing costs in exchange for a higher rate (CFPB).
The grid also depends on the lock period. Holding a price longer generally costs more, so a 60-day lock sits at a different spot than a shorter one. See how a rate lock works.
Risk-based adjustments move your loan around the grid. For loans sold to Fannie Mae, those are loan-level price adjustments, published in Fannie Mae's LLPA Matrix. The matrix says LLPAs are assessed on features like credit score, loan purpose, occupancy, number of units and product type, are based on loan-to-value, and are cumulative (Fannie Mae LLPA Matrix, dated 09.30.2026). Freddie Mac publishes its own adjustments. FHA, VA and USDA loans are priced differently because they aren't sold to Fannie or Freddie, and their own fees, like FHA mortgage insurance or the VA funding fee, are separate from the rate.
The CFPB lists seven factors that affect the rate you're offered (CFPB):
Occupancy and property type matter too. A second home, investment property, condo or two- to four-unit home can carry different adjustments than a single-family primary residence, and a cash-out refinance is priced differently than a purchase.
Two buyers on the same street, same day, same lender can see different rates because their files land on different cells of the same grid: different scores, different down payments, one is buying a condo, one is buying a duplex, one locks for longer. Different lenders also have different costs and appetites, which is why quotes differ from lender to lender even for the same file.
This example is made up and uses no rate figures. Two Fort Worth buyers apply on the same morning. Alex has a higher credit score and puts more down. Sam has a lower score, puts less down and is buying a condo. The lender's rate sheet is identical for both. Alex's file picks up fewer risk adjustments, so Alex is offered a lower rate for the same points. Sam's adjustments stack, since LLPAs are cumulative, so Sam either accepts a higher rate or pays points to buy it down. That afternoon the bond market moves and the lender reprices. Neither quote holds unless it's locked.
Want to know what actually drives the rate on your loan? I'll pull your real credit, show you which adjustments apply to your file, and lay out the points-versus-credits trade-offs on the same day's sheet, so you know what you can change before you lock. Schedule a call, or when you're ready, start an application.
Links checked Oct 21, 2026.
About the author: McKade Lively, NMLS 2704474, American Pacific Mortgage Corporation dba True North Home Loans, NMLS 1850.
Equal Housing Opportunity.
Last reviewed: Oct 2026