Yep, Jerry is correct.

Although there are a few insurances that do not allow the 80% rule, most do, and this allows six doses saved up every month. Do that for five months and you have your month of emergency meds saved up.

They allow this on even controlled substances, and the law allows this as well, and if it is written in the law then you should have no problem if people ask you about it.

It is the cheapest way to do it (just two extra copays in a year!), unless it's one of those 4 dollar meds, then just get an extra prescription from your doc or just get the refill and tell them you are paying cash. Don't try the extra refill on a controlled substance, though, it raises red flags. For that, stick with the 80% rule, i.e. 24 days must pass in a 30 day supply.

The mail order option is actually not that great because you only have the extra meds for a couple of months, then you still have to wait the alloted time before you get more.