Generally, the program banks that participate in Betterment Cash Reserve pay interest rates that are tied to the federal funds rate, which is the rate at which banks can loan money to each other, and is set by the Federal Reserve. The interest rate you receive on Cash Reserve will typically change as a result of the Federal Reserve changing its target federal funds rate. When the federal funds target rate increases or decreases, the rate we can offer through Cash Reserve can also fluctuate with ...