How does the IRS expect HSA "receipts for medical expenses" to look in praxis?

For me this was the easiest when I had a debit card from the HSA. I generally keep three items related for each visit.

1. The paperwork from the doctors office. It gives the medical codes and basic notes from the visit. It lists the procedures done, and any tests ordered.

2. The Explanation of Benefits (EOB) from the insurance company. It boils down the visit to how much it was, how much they paid, and what I was responsible for.

3. Periodically I download statements from the HSA debit card. I then match each line on the statement to the EOB and doctors paperwork. The statement lists the name provider, I have to match it to the specific visit.

A spreadsheet helps.

Over time the paperwork from the doctors office has changed from a carbon copy to a computer printout. Sometimes the doctors office has a patient portal so I can get everything in electronic form.

I never pay a doctors bill at the time of service unless the final amount of the bill is known. So I will pay a co-pay at the office at the end of a visit. I will pay for my prescription when I pick it up, or via the website. Otherwise I let them bill me, after the EOB has been issued. I always use the HSA website to send the funds to the provider instead of passing the funds though me.

This year things are changing because I no longer have HSA funds. I still do the first two parts. I have to now be consistent over which credit card I use to pay the bill, so I don't have to look in too many accounts to match the transaction. I also realize that the tracking is not as important for me since the recent tax law changes and the lack of HSA funds means the tracking for IRS purposes isn't relevant any more.

I have not personally been audited for HSA distributions, so this is just my understanding of the rules.

The IRS really only cares about three things:

1. Was the expense a Qualified Medical Expense (QME)?
2. How much was paid out-of-pocket?
3. Does the distribution from the HSA match the cost of the QME?

As you alluded to, a short credit card receipt from a doctor's office would satisfy #2, but not so much #1. On the other hand, an EOB or bill would satisfy #1 but not #2, since you won't have proof of how much you actually paid. So if you have both:

• a credit card paper chit with amount and date, proofing that I paid that doctor on that day, and
• a printout from the insurance website with what the doctor billed them, and what my share of the deductible is

... that would be enough to satisfy both #1 and #2. Requirement #3 would only be an issue if the amount you paid out-of-pocket did not match the actual amount billed by the doctor.

If you overpaid the doctor $1.73 and don't bother getting a refund, then just reimburse yourself from the HSA for $1.73 less than what you actually paid. That way the amount on the EOB/bill and the amount taken from the HSA match. For example:

You pay the doctor $150. Insurance later comes back and says the cost is $148 dollars. You never pursue a refund, so you simply reimburse yourself for $148 from the HSA and eat the $2 difference.

If you underpay the doctor and they don't bother billing you for the balance, then simply reimburse from the HSA what you actually paid. For example:

You pay the doctor $95. Insurance comes back and says you owe $98. The doctor never sends you a bill, so you reimburse $95 from the HSA.

You can makes things easier for yourself by immediately reimbursing yourself for smaller expenses ($10-$20 prescriptions), and only letting the larger expenses ($500 dental work) "ride" until years down the line. This will cutdown on paperwork and arguably lower the chance of an IRS audit, since you take some distribution over time, and not just all at once.