Employees who are participating in a HSA must file a Form 8889 along with their 1040. Form 8889 must be filed for any year that an individual makes or receives HSA contributions or any year that they take a HSA distribution.
Employers will report any contribution it made to the HSA on the W-2 on box 12. In addition, individuals should receive a Form 5498-SA from the HSA trustee that reports total contributions made during the year and the value of the HSA at year end. If any distributions were taken during the year, the trustee will also send a Form 1099-SA to the individual reporting total distributions made for the year. These three forms will be used to complete Form 8889.