My experiment in which I am both scientist and subject (uhoh) has got off to a somewhat rocky start.
I elected an additional employee contribution, and both employer and employee contributions show up on my twice-monthly pay slips, but until today (yes, 45 days into the year) not a single dollar of that actually arrived in my HSA bank account, so no funds were yet available from which to pay expenses. So, now, finally there's funds in there and I could start to pay bills.
Now I have additional stuff to figure out -- which is to say: What can I pay from my HSA? I know what kind of expenses, but what about when they are incurred? The IRS publication I read makes it sound like I can have a qualifying distribution from the account for expenses incurred since the date the HSA was established, which I read as meaning the funds didn't have to be in the HSA when I went to the doctor in order for me to be allowed to use them to pay the doctor's bill. There's a catch, however. Due to frustrating delays related to ... I'm not sure what ... I wasn't able to open my HSA until late January, and it sure reads to me like the date the account was established is what matters, not the date I was eligible to contribute to an HSA (i.e. January 1st, the first day of coverage under the HDHP). This would be unfortunate, since we did have some expenses in early January. :/ I'm not much looking forward to trying to get straight answers from either our finance people at my company (this is more specialized detail than I honestly think they can be expected to know), the benefits people my company uses, or the HSA bank.
So far this experiment has not been a terrible failure, but it's not been by any stretch of the imagination a resounding success.