To use your HSA funds for a humidifier, you must meet the following criteria:
“The IRS considers humidifiers “dual-purpose” items. This means they can serve both general wellness purposes and medical purposes.” Crates Health Recommended Humidifier Options can i buy a humidifier with my hsa
The LMN must be issued before you buy the device; you cannot retroactively apply an LMN to a past purchase for reimbursement. To use your HSA funds for a humidifier,