If you have a Health Savings Account (not an FSA), now is the time to check that you have contributed the maximum allowed under IRS regulation. If you have, congrats and go you! If you have not, perhaps consider depositing that Christmas check from your parents as your catch-up contribution.
If you have over-contributed, talk with your finance department about reversing your last deposits in order to get back under the cap. Yes, there is a reversal process - there's usually just a single form - and it can be processed directly by the HSA rather than via payroll.
... This message is brought to you by me doing my HSA math and realizing that I need to divide by twenty-six paychecks, not twenty-four.