While FSA plan years can vary, the vast majority of plans will end on 12/31 and the remainder of the funds will be forfeited to the FSA plan sponsor if they are not spent. However, employers can choose one (or neither) of two regulations: the $500 rollover or the 2.5 month grace period. The $500 rollover allows FSA users to roll over up to $500 into next year's account, while the 2.5 month grace period gives FSA users 2.5 months after the end of their plan year to make purchases and submit claims for reimbursement. So if your plan ends on 12/31, the only way you can still spend 2016 funds is if you have the 2.5 month grace period extension that ends on 3/15. Double check with your benefits administrator to find out when your 2016 funds expire and how long you have to spend or file claims.