Code W in Box 12b of W-2 includes the TOTAL amount contributed to an HSA, both by the employer and the employee
That is how the IRS says it should be. Any contribution to an HSA made by an employer on behalf of an employee is not excluded from income and must be added to the AGI of the employee on the employee’s California return.
The employee contribution of the HSA in box 12 reduces the federal income reported on the W-2 in box 1 automatically but the CA income in box in box 16 should be including the employee and employer's box 12 contributions already ... you do not need to add them in again.
