The FAQ below explains how to enter your W-2 box 12 information in TurboTax. Because box 12 can have multiple entries (12a, 12b, 12c, 12d), you may need to click +Add another row under the box 12 area to open additional fields. (Click the screenshot below to enlarge it for reference.)
How do I fill out the Box 12 information from my W-2? https://ttlc.intuit.com/replies/4785646
