Each entry on your W-2 for Box 12 will show a code and an
amount. The amount listed with Code W beside it indicates Health
Savings Account (HSA) contributions. It may be shown in any of the lines for Box 12.
The designation for 12 A, 12 B, 12 C, and 12 D are there to
allow 4 different codes and amounts to be reported in Box 12.
To learn more about the W-2 Box 12 codes, see the
information below.
https://ttlc.intuit.com/replies/3300234
