“
This modification permits § 125 cafeteria plans to be amended to
allow up to $500 of unused amounts remaining at the end of a plan year in a
health FSA to be paid or reimbursed to plan participants for qualified medical
expenses incurred during the following plan year, provided that the plan does
not also incorporate the grace period rule.”
http://www.irs.gov/pub/irs-drop/n-13-71.pdf