As of January 2013, most employers must report the aggregate annual cost of employer-provided coverage for each employee on the Form W-2. The W-2 reporting requirement is informational only and it does not require taxation on any health plan coverage. Reporting is required for most employer-sponsored health coverage, including group medical coverage. Small Employer Exception: Until further guidance is issued, the W-2 reporting requirement does not apply to employers required to file fewer than 250 Form W-2s in the prior calendar year. To learn more about the requirements, as well as exclusions, visit irs.gov/aca.