Does the co-signer have to be on the registration and title?

Yes, a co-signer typically needs to be listed on the registration and title of the vehicle to ensure that they have a legal interest in the ownership and can be held responsible for any obligations associated with the vehicle. This is particularly important when financing a vehicle, as the lender may require both the primary borrower and the co-signer to be on the title. However, specific requirements can vary by state, so it's advisable to check local regulations.