IANAL but having been in that situation, I think I can answer. I'm assuming you would be under a TN status. It depends partly on the timeline. Finding a new job

IANAL but having been in that situation, I think I can answer. I'm assuming you would be under a TN status. It depends partly on the timeline. Finding a new job is relatively easy (depending on your experience and the market) and you can file for an I129 (Change of Status I think) to get a new TN status or change of employer but the main thing to remember is to file this prior to you receiving your last pay check. It will also require for you to show your last two pay stubs with your demand to show that you've actually worked at your first place of employment but it's relatively simple. However, going back to the border is much quicker and you get a decision on the spot compared to filing the I129 which takes 15 days and costs ~1500$ (compared to a new status application at the border, 50$). If the new job doesn't work out (layoff/fired/quit/etc..) you are supposed to leave on your last day of work. There's no "grace period". If you want to stay you need to apply for a change of status to a B-2 in order to wrap up US affairs which will give you up to 6 months. Let's say you find a new job within a month, I doubt you will actually have issues but you do need to leave the country and come back.