Therefore, the United States Prime Rate is now 4.25%, EFFECTIVE TOMORROW (March 4, 2020.) The next FOMC meeting and decision on short-term interest rates will be on March 18, 2020. Prime Rate Definition. The U.S. Prime Rate is a commonly used, short-term interest rate in the banking system of the United States. Therefore, the United States Prime Rate is now 4.25%, EFFECTIVE TOMORROW (March 4, 2020.) The next FOMC meeting and decision on short-term interest rates will be on March 18, 2020. - The 12 month forecast for the Prime Interest Rate is in the table at the top of this page. Forecast-Chart.com is forecasting that Prime Loan Interest Rates will be roughly 5.50% in one year. The table shows a HDTFA of 1.03% which suggests that the March, 2020 rate could easily fall between 6.53% and 4.47%.