Typically yes. You'll need to show proof of insurance even for temporary tags.
State laws differ. However, most states do require you to have car insurance on a registered vehicle, even if you just bought it and have only paper or temporary plates on it.
There are some states that require you to show proof of car insurance when you title and register a car, and thus get your paper or real license plates (tags).
In other states, you do not have to show actual proof of auto insurance when you get your paper or permanent plates, but you are expected to have at least the state required liability coverages on the vehicle.
In many states, when you sign your registration and license plate paperwork, you attest to the fact that the car is insured and will remain covered by car insurance for the whole registration period.
If you are getting the paper plate from a dealer, it will depend upon state laws first and guidelines of the dealership second. If the law does not require that you show proof of insurance, the rules of the dealership may require you to show proof of insurance to drive the car off the lot with the paper plates.
Since states procedures for this differ greatly, we would recommend that you check with your state's Department of Motor Vehicles to find out your state's process is for obtaining paper plates and if you must have car insurance already in place to get this type of tag for your vehicle.
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