Yes, if an employer contributes amounts to an employee’s HSA that exceed the maximum annual contribution allowed in Code Sec. 223(b) due to an error, the employer may correct the error. For 2008, the contribution limits are $2,900 for self-only coverage and $5,800 for family coverage.
In this case, at the employer’s option, the employer may request that the financial institution holding the HSA funds return the excess amounts to the employer. Alternatively, if the employer does not recover the amounts, then the amounts must be included as gross income and wages on the employee’s Form W-2 for the year during which the employer made contributions.
If, however, amounts contributed are less than or equal to the maximum annual contribution allowed in Code Sec. 223(b), the employer may not recoup any amount from the employee’s HSA.
Source: IRS Notice 2008-59, Q&A-24, June 25, 2008.