The IRS and Treasury Department recently changed the rules for flexible-spending accounts. Now employers have the option to let employees carry over up to $500 remaining in the account from one year to the next. They aren’t required to make the change, but if they do offer the carryover, they can no longer provide a grace period until March 15 to use the money in the account. If your employer still offers a grace period until March 15, now is the sweet spot when you can get maximum coverage from your FSA for large, uninsured medical expenses (such as dental work or laser eye surgery). You can use any money left over from last year, as well as the full amount you plan to contribute for 2014, even though you haven’t actually had the money deducted from your paychecks yet.