Understanding mortgage rates
What drives mortgage rates, the difference between rate and APR, and how lenders set the specific rate they offer you.
1. How mortgage rates are set
Mortgage rates aren't set by individual lenders or the government — they're determined by financial markets, primarily the bond market. Understanding this explains why rates can change daily (or even multiple times a day) and why they sometimes move in unexpected directions.
The most important benchmark for 30-year fixed mortgage rates is the yield on the 10-year U.S. Treasury note. Mortgage rates typically trade at a spread above the 10-year Treasury — historically around 1.5–2.0 percentage points, though that spread widened significantly during the 2022–2024 period of rate volatility.
2. The Fed and mortgage rates
The Federal Reserve sets the federal funds rate — the overnight rate that banks charge each other to lend reserves. This is not the same as your mortgage rate, and the relationship is indirect.
When the Fed raises rates, it's trying to slow the economy and reduce inflation. Higher short-term rates generally push bond yields higher over time, which raises mortgage rates. But the connection isn't one-to-one or instant. Mortgage rates can fall even while the Fed is raising the funds rate, if markets expect the hikes to slow inflation and eventually lead to cuts.
When the Fed "raises rates," it raises the federal funds rate — an overnight lending rate. This is not your mortgage rate. Mortgage rates are set by the market for long-term debt, primarily driven by the 10-year Treasury yield and investor demand for mortgage bonds.
3. Mortgage-backed securities
Most mortgages are sold by lenders into the secondary market, where they're packaged into mortgage-backed securities (MBS) and sold to investors. This is why your lender can make a loan and then immediately have cash to make the next one.
Mortgage rates are directly tied to MBS prices. When investors want to buy more MBS (demand rises), prices rise and yields fall — mortgage rates drop. When investors are selling MBS, prices fall and yields rise — mortgage rates increase. This market trades continuously, which is why rates can change daily.
4. What determines your rate
Market rates are the baseline. Your individual rate is the market rate adjusted up or down by loan-level price adjustments (LLPAs) — a matrix of risk factors that Fannie Mae and Freddie Mac publish. Lenders use these to price loans. Key factors:
| Factor | Rate impact |
|---|---|
| Credit score (FICO) | Largest single factor; 740+ vs 660 can mean 0.5–1%+ difference |
| LTV ratio (down payment) | Less down = higher rate; 20%+ down avoids the worst adjustments |
| Loan type | Primary residence < second home < investment property |
| Loan size | Jumbo loans (above conforming limits) carry different rates |
| Fixed vs. ARM | ARMs start lower; 30yr fixed is the baseline |
| Property type | Condo / multi-family add adjustments vs. single-family |
5. Rate vs. APR
The interest rate is the annual cost of borrowing the principal, expressed as a percentage. The APR (Annual Percentage Rate) is the interest rate plus most fees and costs, also expressed as an annual percentage.
APR is always equal to or higher than the interest rate. The bigger the gap between rate and APR on a given loan, the more fees the lender is charging. When comparing loans from different lenders, compare APRs — not just rates. A lender with a lower rate but higher fees may actually cost more.
One caveat: APR is calculated assuming you keep the loan for its full term. If you'll sell or refinance in 5–7 years (as most people do), the true cost of high upfront fees relative to a slightly higher rate may differ from what APR suggests.
6. Discount points
Discount points are upfront fees paid to permanently reduce your mortgage rate. One point = 1% of the loan amount. Typically, one point buys down the rate by approximately 0.25%, though the actual reduction varies by lender and market conditions.
Whether to pay points is a break-even calculation: divide the upfront cost by the monthly savings. If a point costs $3,000 and saves $50/month, break-even is 60 months. If you'll be in the home beyond 5 years, paying the point makes sense. If you're likely to sell or refi before then, it doesn't.
7. Rate locks
When you apply for a mortgage, the rate the lender quotes you is subject to change until you lock it. A rate lock is a commitment from the lender to hold a specific rate for a defined period — typically 30, 45 or 60 days (longer locks usually cost more).
Lock too early and you risk expiring before closing; don't lock and you risk rates rising while you're in process. Most buyers lock at application or shortly after the appraisal is complete, once the loan timeline is clearer. Some lenders offer float-down options — the ability to take a lower rate if rates drop after locking, usually for a fee.
8. How to shop for rates
Rate shopping matters. Studies consistently show that borrowers who get multiple quotes save significantly over the life of their loan.
- Get at least three Loan Estimates — the standardized form lenders must provide within 3 business days of application. These make apples-to-apples comparison possible.
- Compare APRs, not just rates — a lower rate with high fees may cost more.
- Shop within 45 days — multiple mortgage inquiries within a 45-day window count as one hard inquiry under FICO's rate-shopping rules.
- Check both banks and mortgage companies — non-bank mortgage lenders often have competitive rates and can be faster to close.
- Ask about lender credits — you can take a slightly higher rate in exchange for the lender paying some or all of your closing costs. Useful if you're short on cash or plan to refi or sell soon.