If you are not replacing your vehicle within 30 days, the plate must be turned in. Keep your registration as proof of having the plate to avoid a new license fee ($200+), but when you do get a new vehicle, you will have a tag replacement charge (about $40) the same as when you get a new plate for a vehicle you already have registered.
It can be mailed, it dropped off with the tax collector's office, or transferred to another vehicle.
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