The short answer is no, you're almost certainly not going to face theft charges for an honest luggage mix-up. But the longer answer involves some important legal distinctions that could make the difference between a harmless mistake and actual criminal trouble. What matters most isn't the fact that you took someone else's bag—it's what was going through your head when you grabbed it, and what you do once you realize the error. Theft requires proving you intended to steal, which is nearly impossible when two suitcases look identical, and you genuinely thought you were taking your own property. That said, the law does care about how you handle the situation after discovering your mistake, and that's where things can potentially get complicated if you're not careful about making things right.