My HSA account was transferred, but it seems HSA Bank refuses to tell anyone the earnings on the contributions. The excess contribution form asks *you* to also include what the earnings on that excess contribution was.
You are completely right about the timing of the withdraw and the earnings. Because of this, I moved my whole balance to cash (sold all equity investments which move around daily). I know the interest is paid on the last day of the month, so I am processing the excess contribution withdraw form on the first of the month when I know what the earnings are. Really is such a pain that I shouldn't have to do.
