Under the Illinois Promissory Note and Bank Holiday Act, banks are permitted to close at noon on each Saturday and all day on Sunday. Banks may also remain closed on the holidays that are specified in the Act, which include the first day of January but not the last day in December. Therefore, you would have to follow the procedures in Section 17(c) for a special closing if you wish to close before noon on Saturday, December 31. These procedures include sending a copy of a board resolution authorizing the closure to the Director of Banking and posting a copy of it in the lobby of the main bank location and any branch locations for at least three weeks prior to the day the bank will be closed.