Prime Rate Definition

What Is the Prime Rate?

The term prime rate refers to the interest rate that commercial banks charge their most creditworthy customers. The Federal Reserve (Fed) sets the federal funds overnight rate which serves as the basis for the prime rate, which is the starting point for other interest rates. It is the most commonly used benchmark used by banks and other lenders when setting their interest rates for various products, such as credit cards and home loans.

Key Takeaways

  • The prime rate is the interest rate that commercial banks charge their most creditworthy corporate customers.
  • The prime rate is based on the federal funds rate.
  • Banks generally use a fed funds rate + 3 to determine the current prime rate.
  • The rates for mortgages, small business loans, and personal loans are based on the prime rate.
  • Lenders generally charge the most creditworthy clients the prime rate while others receive an interest rate based on their credit score of prime plus another percentage.
  • The most used prime rate is the rate that the Wall Street Journal publishes daily.

Prime Rate

How the Prime Rate Works

Interest rates are a percentage of the amount that lenders charge on any loans they grant to borrowers. It acts as a form of compensation for the risk that lenders assume based on the borrower’s credit history and other financial details. These rates are normally noted annually as the annual percentage rate (APR).

The prime rate is the interest rate that commercial banks charge their most creditworthy customers, generally large corporations. The prime interest rate, which is also called the prime lending rate, is largely determined by the federal funds rate set by the Federal Open Market Committee (FOMC).The fed funds rate is the overnight rate that banks use to lend to one another. Banks commonly use a combination of the federal funds rate + 3 to determine the prime rate.

As noted above, lenders charge their most creditworthy clients the prime rate for mortgages, small business loans, or personal loans. For others, the prime rate forms the basis or starting point for most other interest rates. The interest these borrowers are charged, which is based on their credit scores and credit histories, is normally prime plus a certain percentage. Those who have a good credit score would be charged, say, prime plus 9% for a credit card while those with a lower score may get a rate of prime plus 15%.

The prime rate plus a percentage forms the base of almost all other interest rates.

Determining the Prime Rate

The prime rate is an interest rate determined by individual banks and used as a base rate for many types of loans, including loans to small businesses and credit cards. Although the Federal Reserve has no direct role in setting the prime rate for banks, many financial institutions choose to set their prime rates based partly on the target level of the federal funds rate established by the FOMC.

One of the most used prime rates is the one that the Wall Street Journal publishes daily. As noted above, banks generally use fed funds + 3 to determine the current prime rate. The prime rate in the United States was 6.25% as of September 2022. That's an increase from 4.75%, which was the rate set in June 2022. The increase occurred at the same time that the Fed raised its fed funds rate range to 3% to 3.25% in September 2022.

Although other U.S. financial services institutions regularly note any changes that the Fed makes to its prime rate, and may use them to justify changes to their prime rates, institutions are not required to raise their prime rates following the Fed.

The federal funds rate is the interest rate at which depository institutions trade funds held at Federal Reserve Banks with each other overnight. When a depository institution has surplus balances in its reserve account, it lends to other banks in need of larger balances.

What Is the Impact of the Prime Rate?

The prime rate affects a variety of bank loans. When the prime rate goes up, so does the cost to access small business loans, lines of credit (LOCs), car loans, mortgages, and credit card interest rates.

Debt with a variable interest rate can be affected by the prime rate because a bank can change your rate. This includes credit cards as well as variable rate mortgages, home equity loans, personal loans, and variable interest rate student loans.

The prime rate is reserved for only the most qualified customers, those who pose the least amount of default risk. Prime rates may not be available to individual borrowers but are offered to larger entities, such as corporations and stable businesses. If the prime rate is set at 5%, a lender still may offer rates below 5% to well-qualified customers which are not considered a mandatory minimum.

How Has the Prime Rate Changed Over Time?

Prime rates fluctuate over time depending on the movement of the federal funds rate. The most recent prime rates were:

9/22/2022: 6.25%

7/28/2022: 5.50%

6/16/2022: 4.75%

5/5/2022: 4.00%

3/17/2022: 3.50%

3/16/2020: 3.25%

What Is Not Affected by a Change in the Prime Rate?

Any existing loan or line of credit held with a fixed rate is not affected by a change in the prime rate. This may include student loans, fixed-rate mortgages, and savings accounts.

What Does a Change in the Prime Rate Signal?

A change in the prime rate often means that the Federal Reserve has changed its fund rate. For example, an increase to the federal funds rate may be to fight growing inflation and control price growth.

The Bottom Line

The prime rate is the interest rate that commercial banks charge creditworthy customers and is based on the Federal Reserve's federal funds overnight rate. Banks generally use a fed funds + 3 to determine the current prime rate. The rate forms the basis for other interest rates, including rates for mortgages, small business loans, or personal loans.

Article Sources
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  1. Federal Reserve Board. "FAQs: What Is the Prime Rate, and Does the Federal Reserve Set the Prime Rate?"

  2. Wall Street Journal. "Money Rates."

  3. Federal Reserve Bank of Minneapolis. "How Do Lenders Set Interest Rates on Loans?"

  4. Bank of America, Newsroom. "Prime Rate Information."

  5. Federal Reserve Board. "Implementation Note Issued Sept. 21, 2022."

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