The W-2 Form for 2012 reporting must provide tax information from January 1, 2012 – December 31, 2012. The actual form must be distributed to employees by January 31st, 2013. In addition, employers issuing 250 or more W-2 forms must include the cost of health coverage on the W-2. For most plans, the benefit amount reported on the W-2 should include both the portion the employee contributed towards the health insurance premium as well as the portion the employer contributed to the plan.