If you have spent any time reading about interest rates, you have probably seen three terms used almost interchangeably: the prime rate, the federal funds rate, and SOFR. Financial media often blurs the lines between them, which leads to real confusion when you are trying to understand why your credit card APR changed, what rate your SBA loan is actually based on, or why your adjustable-rate mortgage uses a completely different benchmark than your business line of credit. These three rates are related — they all respond to Federal Reserve policy — but they measure different things, affect different financial products, and move in subtly different ways. Here is what borrowers actually need to know.
The Three Rates at a Glance
Before going deeper, here is the current snapshot as of March 2026:
Federal Funds Rate: 3.50 – 3.75 percent (target range set by the FOMC on January 28, 2026)
Prime Rate: 6.75 percent (published by the Wall Street Journal, always federal funds rate + 3%)
SOFR (Secured Overnight Financing Rate): approximately 3.65 percent overnight rate; 30-day average around 3.58 percent (published daily by the Federal Reserve Bank of New York)
Notice that these are all in the same general neighborhood of 3.5 to 6.75 percent — but the differences between them matter enormously depending on which financial product you are using.
The Federal Funds Rate: Where Everything Starts
The federal funds rate is the wholesale rate that the entire U.S. interest rate system is built on. It is the rate that banks charge each other for overnight loans of their reserve balances held at the Federal Reserve. You will never borrow at this rate directly — it is a bank-to-bank rate — but it drives everything else.
The Federal Open Market Committee sets a target range for this rate (currently 3.50 to 3.75 percent) and uses open market operations — buying and selling Treasury securities — to keep the actual rate within that band. The effective federal funds rate (the volume-weighted median of actual overnight transactions) typically sits right in the middle of the target range.
When headlines say “the Fed raised rates” or “the Fed cut rates,” they are talking about changes to this target range. The FOMC meets roughly eight times per year to evaluate economic data and decide whether to adjust it. Each change — typically in increments of 0.25 percent — cascades through the financial system within days.
Products directly affected: None that consumers use directly. But the federal funds rate is the foundation for both the prime rate and SOFR, which in turn affect nearly every lending product on the market.
The Prime Rate: The Consumer Lending Benchmark
The prime rate is the interest rate that commercial banks charge their most creditworthy business customers. The Wall Street Journal publishes the most widely referenced version, defined as the base rate posted by at least 70 percent of the 10 largest U.S. banks.
The formula is mechanical and has been nearly invariant for decades:
Prime Rate = Federal Funds Rate (upper bound) + 3.00%
With the federal funds rate at 3.50 to 3.75 percent, the prime rate sits at 6.75 percent. When the Fed changes rates, the prime rate follows within one to two business days by exactly the same amount. There is no lag, no negotiation, no discretion — it is automatic.
The prime rate is the dominant benchmark for consumer lending products. If you have a variable-rate financial product in the United States, there is a strong chance it references the prime rate somewhere in its terms.
Products priced off the prime rate: Credit cards (almost all variable-rate cards), HELOCs, some adjustable-rate mortgages, SBA 7(a) loans, many business lines of credit, some personal loans with variable rates.
SOFR: The Post-LIBOR Institutional Benchmark
SOFR — the Secured Overnight Financing Rate — is the newest of the three and the one that generates the most confusion. It was created to replace LIBOR (the London Interbank Offered Rate), which was phased out in June 2023 after the rate-rigging scandal that undermined trust in the global financial system.
SOFR measures something fundamentally different from both the federal funds rate and the prime rate. It captures the cost of borrowing cash overnight using U.S. Treasury securities as collateral. This is called the “repo market” (short for repurchase agreement), and it is enormous — the New York Fed reports that SOFR is based on roughly $2 trillion in daily transaction volume. That massive volume is exactly why regulators chose it as LIBOR’s replacement: it is nearly impossible to manipulate a rate derived from that much actual trading activity.
The overnight SOFR rate currently sits around 3.65 percent — very close to the federal funds rate, which makes sense because both measure the overnight cost of borrowing between major financial institutions. The difference is that SOFR transactions are secured by Treasury collateral (making them slightly lower risk), while federal funds transactions are unsecured.
SOFR comes in multiple tenors: overnight, 30-day average, 90-day average, and 180-day average. There is also CME Term SOFR, which provides forward-looking 1-month, 3-month, 6-month, and 12-month rates based on futures market pricing. These term rates are what most lending products actually reference, since borrowers need to know their rate for a specific upcoming period, not just for tonight.
Products priced off SOFR: Most new adjustable-rate mortgages, many commercial real estate loans, syndicated business loans, student loan refinancing products, and — as of March 2026 — SBA 7(a) loans (where lenders can now choose SOFR as an alternative base rate alongside prime).
Side-by-Side: How They Compare
Here is a direct comparison across every dimension that matters for borrowers:
Current rate (March 2026): Federal funds: 3.50-3.75%. Prime: 6.75%. SOFR (overnight): ~3.65%.
Who sets it: Federal funds: FOMC (8 times per year). Prime: Commercial banks (follows Fed automatically). SOFR: Market transactions (published daily by NY Fed).
What it measures: Federal funds: Cost of unsecured overnight interbank lending. Prime: Base rate for best commercial customers (fed funds + 3%). SOFR: Cost of secured overnight lending backed by Treasuries.
Transaction volume: Federal funds: ~$80-100 billion daily. Prime: N/A (derived rate, not transaction-based). SOFR: ~$2 trillion daily.
How it moves: Federal funds: Discrete jumps at FOMC meetings (0.25% increments). Prime: Mirrors fed funds moves exactly, 1-2 days later. SOFR: Continuous daily fluctuations, with larger moves around quarter-end and FOMC decisions.
Collateral: Federal funds: Unsecured. Prime: N/A. SOFR: Secured by U.S. Treasuries (lower risk).
Primary users: Federal funds: Banks lending to each other. Prime: Consumer lenders pricing credit cards, HELOCs, business loans. SOFR: Institutional lenders, mortgage securitizers, commercial real estate, derivatives markets.
Why SOFR Replaced LIBOR (and Why It Matters to You)
Until June 2023, LIBOR was the world’s most referenced interest rate benchmark — underpinning an estimated $300 trillion in financial contracts globally. The problem was that LIBOR was based on estimates submitted by a small panel of banks about what they thought they could borrow at, not on actual transactions. When it emerged that banks had been manipulating their submissions to benefit their own trading positions, regulators decided the system needed a replacement built on real market data.
SOFR was the answer for U.S. dollar markets. It is calculated from actual, observable Treasury repo transactions — roughly $2 trillion worth every day. That volume makes it both highly reliable and extremely difficult to manipulate. The Federal Reserve endorsed SOFR as the preferred replacement and the transition was completed on schedule.
For borrowers, the transition mostly happened behind the scenes. If you had an ARM or a business loan that referenced LIBOR, your lender converted it to a SOFR-based rate using adjustment formulas designed to keep your effective rate roughly the same. New lending products — particularly adjustable-rate mortgages backed by Fannie Mae and Freddie Mac — now exclusively use SOFR.
There is one practical difference worth knowing: SOFR tends to be slightly more volatile day-to-day than the old LIBOR was, particularly around quarter-end dates when demand for Treasury collateral spikes. However, the 30-day and 90-day averages smooth this out, and for consumer products priced off term SOFR (which uses futures market expectations), the experience is quite stable.
Which Rate Affects Which Loan: A Practical Guide
This is where it gets actionable. Knowing which benchmark your loan uses tells you exactly how it will respond to Fed policy changes.
Credit cards → Prime rate. Your APR is prime + your margin. It adjusts within 1-2 billing cycles of any Fed move. This is the most direct and immediate pass-through in consumer lending.
HELOCs → Prime rate. Same as credit cards — prime + margin, adjusts quickly. The difference is the balance size, so each 0.25% move matters more in dollar terms.
Adjustable-rate mortgages (post-2023) → SOFR. New ARMs from Fannie Mae and Freddie Mac use the 30-day SOFR average. Adjustments happen annually or semi-annually after the initial fixed period, not with every Fed meeting. Your mortgage servicer recalculates based on the SOFR value at a specific lookback date.
SBA 7(a) loans → Prime rate OR SOFR (lender’s choice, as of March 2026). Most lenders still use prime, but the SBA now permits SOFR and Treasury note rates as alternatives. Ask your lender which benchmark they use — it affects how your rate adjusts over time.
Business lines of credit → Usually prime rate for smaller facilities from online lenders like Bluevine. Larger syndicated facilities from banks increasingly use SOFR.
Commercial real estate loans → Predominantly SOFR, especially for larger institutional loans. Smaller community bank CRE loans may still reference prime.
Private student loan refinancing → Varies by lender. Some use prime, others use SOFR. Variable-rate student loans should specify the index in your loan agreement.
Fixed-rate mortgages, auto loans, federal student loans → None of the above. These are fixed at origination and do not reference any ongoing benchmark. However, the rates available to new borrowers at any given time are influenced by the overall rate environment that the federal funds rate creates.
When Does It Matter Which Benchmark Your Loan Uses?
For most borrowers, the difference between a prime-based loan and a SOFR-based loan is small, because both benchmarks track the same underlying Fed policy. When the Fed cuts by 0.25 percent, both the prime rate and SOFR decline by approximately 0.25 percent. Your payment drops by roughly the same amount either way.
But there are a few situations where the benchmark choice does matter:
Timing of adjustments. Prime-based products (credit cards, HELOCs) adjust almost immediately after a Fed move. SOFR-based products (ARMs, some business loans) may use lookback periods or adjustment dates that create a lag. If the Fed cuts in June but your ARM adjusts in January, you don’t see the benefit for months.
Day-to-day volatility. SOFR can spike temporarily around quarter-end dates when Treasury repo markets get tight. The 30-day average smooths this out, but if your loan references overnight SOFR without averaging, you could see brief rate spikes unrelated to Fed policy. This is rare in consumer products but worth understanding for commercial borrowers.
The 3-percentage-point gap. The prime rate is always about 3 percentage points above both the federal funds rate and SOFR. This means the margin your lender quotes you on a prime-based loan will look very different from the margin on a SOFR-based loan — even if the total rate is similar. A loan at “prime + 2%” (8.75% today) is roughly equivalent to a loan at “SOFR + 5.10%” (8.75% today). The headline margin looks different, but the out-of-pocket cost is the same. Do not compare margins across benchmarks without doing this math.
Frequently Asked Questions
Is SOFR higher or lower than the prime rate?
SOFR is significantly lower — currently about 3.65 percent compared to the prime rate at 6.75 percent. However, this does not mean SOFR-based loans are cheaper. Lenders add a larger margin on top of SOFR to arrive at a similar total rate. A loan at prime + 2% and a loan at SOFR + 5.1% cost the borrower roughly the same amount.
Why does my credit card use the prime rate instead of SOFR?
Credit cards have used the prime rate as their benchmark for decades, and the system works well for that product. The prime rate adjusts in predictable, discrete increments (matching Fed decisions), which makes it easy for issuers to communicate rate changes to cardholders. SOFR’s daily fluctuations would create unnecessary complexity for a product that millions of people use.
Can I choose whether my SBA loan uses prime or SOFR?
The lender chooses the benchmark, not the borrower. As of March 2026, SBA-approved lenders can use the Wall Street Journal prime rate, the SBA optional peg rate, 30-day SOFR, or 5- and 10-year Treasury notes as the base rate for 7(a) loans. You can ask your lender which benchmark they use and compare offers from multiple lenders if the benchmark matters to you.
Did SOFR replace LIBOR completely?
For U.S. dollar lending, yes. The last remaining USD LIBOR tenors were discontinued on June 30, 2023. All new U.S. financial products that previously would have referenced LIBOR now use SOFR (or in some cases, prime or Treasury rates). Legacy LIBOR contracts were converted to SOFR-based rates using adjustment spreads established by regulators.
How does the federal funds rate affect my savings account?
Savings account yields track the federal funds rate closely but with a lag. When the Fed cuts, banks eventually reduce the APY they pay on deposits — though they tend to move more slowly on savings rate reductions than on lending rate reductions. The FDIC publishes weekly national rate data that tracks average deposit yields across the banking system.
The Bottom Line
The federal funds rate, the prime rate, and SOFR are three layers of the same system. The Fed sets the foundation with the federal funds rate. Banks translate that into the prime rate by adding 3 percent. And the broader financial market expresses it through SOFR based on trillions of dollars in actual overnight transactions.
For borrowers, the practical lesson is straightforward: know which benchmark your loans and credit products reference, understand what your margin is, and you can predict almost exactly what your rate will be after any Fed decision. Check your credit card agreements for the “prime plus” language. Review your ARM disclosure for the SOFR index reference. Ask your business loan officer which base rate they use.
That 30 seconds of homework turns you from someone who reacts to rate changes into someone who anticipates them. And in a year where the Fed is expected to cut rates further, anticipation is worth real money.
All rates referenced in this article reflect data as of March 2026 and are subject to change. This content is for informational purposes only and does not constitute financial advice.
References
Federal Reserve Bank of New York — Secured Overnight Financing Rate (SOFR)
Board of Governors of the Federal Reserve System — H.15 Selected Interest Rates
Federal Reserve Bank of St. Louis (FRED) — Effective Federal Funds Rate
U.S. Small Business Administration — 7(a) Loan Terms and Eligibility
