Perhaps I have already found the answer, but be better safe than sorry.
I bought an airplane ticket to my home country (in Europe) and only now I realized that my H1b visa expires 2 days after my return ticket back to the US. Will I be admitted back in US without any problems? Will this affect my i-94 duration of stay somehow?
Also, my green card case has been current for a year, but I haven't filed i-485. Plan to do this once I return.
A US visa is for entry to the US, and is thus usable any day up to, and including, the day it expires.
For H1b, you will generally be admitted until the expiration of your H1b petition (unless your passport expires sooner in which case that will limit how long you are admitted until). So the question is, when does your H1b petition expire?
An H1b visa is usually issued until the expiration of the H1b petition you had when you applied for the visa. So the day your visa expires is probably also the day your original H1b petition expires. If your H1b petition hasn't been extended, then you can only be admitted for 2 days, in which case I am not sure whether the offer will let you in. If your H1b petition has already been extended, then you will be admitted until the date when your new petition expires; and the expiration date of your visa is not a problem at all.
