Employer contributions to your Health Savings Account are reported on Form W-2 Wage and Tax Statement, Box 12 with a code "W." An amount entered here will flow to Line 7, Column C of California Schedule CA. The amount is then added to the income total on Line 16 of California Form 540.
To enter employer contributions for California:
Per the California Instructions for Schedule CA (540):
Employer health savings account (HSA) contribution. Enter the amount of any employer HSA contribution from federal Form W-2, Wage and Tax Statement, box 12, code W on line 1, column C.
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