Wow, I would say you are lucky in ND.  In MN I brought in our taxes on a Monday morning that was suppose to have been postmarked the Saturday before that. They threw my envelope in with a few  hundred others that had come in over the weekend and I got a huge penalty. Mine went into the bank the same day as all the rest but it cost us big time. I think my penalty was  a few hundred dollars. I was a little upset.