You didn't name the state, but since you mentioned 14 characters and ending in WTH, is it Utah? If not, what state?
If it's Utah, it's supposed to be the Employer/Payer's withholding ID number.
I'd first check with your employer to be sure they put the right number there in your W-2, Box 15.
If it's Utah, tell your employer it's looking for a 14-character Employer/Payer's withholding ID number with no hyphens and ending in WTH (i.e., 11 characters plus the WTH).
Also be aware that there has been a quirky glitch for several Utah filers, however, which may or may not be related. Several Utah filers in this forum have said they had to use lower case for the wth part instead of capital letters in order to avoid the error.
