@dmertz, Hmm, when I change the Box 12 Code D amount on the 2019 W-2 to exclude the 414(h) contributions and only include the ~19k 401(k) contributions (won't file that way, just testing to see what happens if I do get a corrected W-2), the amount of federal tax due stays the same. Is this to be expected? Maybe one of the top-line boxes on the W-2 is also incorrect?
