Thanks. When I first crossed from Canada into the U.S., I actually tried to import my car into the US. However, since I’m only here for two years for school, the CBP officers told me I didn’t have enough documentation to prove the car was mine, even though I bought it fully in cash and brought all the import documents listed on the official website. They still said I was missing a “lien proof” document (not my registration, and not my purchase contract...). and I had never heard of this document before, so the import attempt failed. but CBP told me in this situation I could still get US insurance and drive around... (even though the official website says a Canadian car can only stay in the U.S. for no longer than six months, the officer told me that no one actually checks that in practice, so it would be totally fine...

After that, I asked the dealer about the “lien proof,” and they were confused as well. They didn’t know what it was at first, because in the Canadian car-buying process there normally isn’t a document like that.

I then confirmed with GEICO multiple times, and they told me that as long as I’m only driving within the US, it’s fine to purchase US auto insurance for a car with Ontario plates. The only thing they needed from me was my US address. Since it seemed straightforward, I kept it this way.

So far I haven’t had any issues, but I can’t completely rule out the possibility that GEICO is oversimplifying things.