I am sure it starts on the date of purchase, and I am ok with that. I need the time to prepare a lot at the campground where I keep it. I registered the unit today online with Crossroads. In MD, a warranty starts the earlier of the date of manufacture or the date of purchase. Registering the warranty with the maufacturer establishes that. By the way, I bought an extended warranty from the dealer so I am comfortable burning a few months on the front end.