That shouldn't really pose a
problem; or at least not one that will prevent you from filing your tax
return. Please allow me to explain.
The only truly meaningful
elements on a W-2 for income tax filing purposes are your employer's
federal EIN (Employer's ID number), your own Social Security Number (SSN),
and your actual wage data. If there was a mistake made with any of these
items, then that would definitely be something that requires attention.
However, with respect to the state
number ID issue, it won't really matter what you input in Box 15 Employer ID,
as long as the software will accept it (explained below). Simply try
leaving the space entirely blank at first. If there is any issue with Box
15 that prevents e-filing your return with a blank Box 15, and it absolutely
requires some value in the software, then either try using your Federal EIN
here (i.e., enter it over again in the State ID field), or enter a clearly "fictitious" value such as 12345 67890 (with
a space in the middle, or not).
If the TurboTax program asks you for
a state ID number in a specific format, such as needing exactly 9-digits and
ending in XYZ, for instance, then just enter a value that conforms to
that format . . . such as 123456XYZ. This will enable you to bypass the
issue and file your return. In other words, try to be a little creative
here, and just give the software some value (even a made-up one) that it will
accept. You can try several different approaches, until you reach one that works for you.
As you correctly point out in your question, Tennessee does not even tax wage income, so the State ID field on her W-2 is effectively a moot point. As such, this single issue should not
affect the processing of your tax return in any manner, no matter what number you input in the State ID field, as long as you can satisfy the
software with some acceptable input (or none at all).
Thank you for asking this question.
