Forget about a letter from your employer, etc. There could be a lot of reasons why your refund was higher than usual. Quite often a joint return can result in more tax than 2 single returns. (The so called marriage penalty.) Given the current uncertainties and the fact that you might fall on hard economic times I would suggest you use Married 1 and your spouse do the same. Any over withholding is not available until you file your return next year and you might be better off with the money in your pocket. No need to contact your employer other than to request to change your withholding. They should send you a new From W-4 to fill out. Remember if you lower your withholding you might get a smaller or no refund next year - might even owe - so if your take home pay is increased stash the difference if things are OK with you or spend it if you need it.
