Flexible spending accounts are an IRS regulated benefit. IRS Publication 502 outlines the federal regulations for Flexible Spending Accounts
Visit the IRS Web site for additional information on the federal guidelines for Flexible Spending Accounts.
IRS Guidelines for Distributions from an FSA
Generally, distributions from a health FSA must be paid only to reimburse you for qualified medical expenses you incurred during the period of coverage. You must be able to receive the maximum amount of reimbursement (the amount you have elected to contribute for the year) at any time during the coverage period, regardless of the amount you have actually contributed. The maximum amount you can receive tax free is the total amount you elected to contribute to the health FSA for the year.