What is a flexible spending account, or FSA?
Flexible spending accounts, also called flexible spending arrangements, allow people to use tax-free contributions from their paychecks for specific expenses. There are several types of FSAs, but the most common are health FSAs, which participants can use to pay for medical and dental costs that aren't covered by insurance.
With an FSA, you'll decide how much you want to contribute (up to the cap) at the beginning of the year, and your employer will deduct a portion of it from every paycheck.
FSAs must follow a "use it or lose it" system where unused funds at the end of the year are forfeited. Employees do get up to a 2.5-month grace period (that is, until March 15th of the following year) to spend FSA funds.