Oops.

Step 1: Get the employer to stop VA W/H and, if you're lucky, you might get them to start DC W/H.  But if they have no DC nexus they're likely not required to (they can, however, register and choose to withhold as a courtesy to the employee.)  Then you'll only have 2 1/2 months of this problem next year.

Step 2: You'll file a VA 763-S (on paper) and attach the W-2 showing withholding.  If you file now they MIGHT have the refund in time to turn it over to DC (along with more tax to cover the higher tax rate).

Rick