Your FSA gives you the opportunity to pay for unreimbursed medical expenses with pre-tax dollars.
While the IRS and your employer may set minimums and maximums for your FSA contribution, you ultimately decide what you are comfortable contributing within those limits.
Your employer may make contributions to your FSA as well or even match your contributions — it all depends on the plan rules set in place.
With your FSA, all your funds for the year are available to you as soon as the plan year begins. You don’t have to wait for funds to build up.