Missouri Revised Statutes Title XL. Additional Executive Departments § 643.340. Operation of vehicle without registration, when allowed--vehicle emission inspection, lawful operation beyond registration expiration, when

1. For the purpose of obtaining an emissions inspection only, a vehicle may be lawfully operated over the most direct route between the owner's usual domicile and an inspection station of the owner's choice, notwithstanding that the vehicle does not have a current state registration license.

2. A vehicle may be lawfully operated from an emissions inspection station to another place for the purpose of making repairs and back to the emissions inspection station, notwithstanding that the vehicle does not have a current state registration license.

3. For the purpose of obtaining an emissions inspection only, a vehicle may be lawfully operated for thirty days beyond the vehicle's registration expiration, notwithstanding that the vehicle does not have a current state registration license, if the vehicle is being driven to reset the vehicle's readiness monitors to pass the on-board diagnostic (OBD) emission inspection described in section 643.303. Vehicle operators shall keep a copy of the most recent failing OBD test results with them to present to law enforcement officers while they are operating the vehicle to reset the vehicle's readiness monitors. The late registration penalty fee described in section 301.050 shall still apply if the vehicle is registered after its current registration expires.