"Q-39. When must a distribution from an HSA be taken to pay or reimburse, on a tax-free basis, qualified medical expenses incurred in the current year?
A-39. An account beneficiary may defer to later taxable years distributions from HSAs to pay or reimburse qualified medical expenses incurred in the current year as long as the expenses were incurred after the HSA was established. Similarly, a distribution from an HSA in the current year can be used to pay or reimburse expenses incurred in any prior year as long as the expenses were incurred after the HSA was established. Thus, there is no time limit on when the distribution must occur. However, to be excludable from the account beneficiary’s gross income, he or she must keep records sufficient to later show that the distributions were exclusively to pay or reimburse qualified medical expenses, that the qualified medical expenses have not been previously paid or reimbursed from another source and that the medical expenses have not been taken as an itemized deduction in any prior taxable year. See Notice 2004-2, Q&A 31 and also Notice 2004-25, for transition relief in calendar year 2004 for reimbursement of medical expenses incurred before opening an HSA."