What are the consequences if an HSA account holder receives a distribution by mistake, but repays the distribution to the HSA?
If there is good evidence that amounts were distributed from the HSA because of a mistake, you may repay the distribution no later than the April 15th following the first year that you became aware of the error. In this situation, the distribution is not subject to income tax or the 10% additional tax and the repayment is subject to excise tax on excess contributions.
