They only require one.
The state of Texas requires that you have 2 plates. One in front and one in the rear.
In the state of Texas, drivers are required to have 2 license plates displayed on the car. One license plate should be in the front and the other plate must be displayed in the rear.
There are 120 different license plates available!
IIRC, the state of Ohio requires two number plates to be displayed.
1 or 2
Two
Two plates were required for automobiles and for trucks. I have a 49 F 1 Pickup that has the original license plates on it.
2 plates on tractor 1 plate on trailer
2
The State of Connecticut requires cars registered there display two license plates, one on the front and one on the rear of the vehicle.(See Related Link, below, for more information.)
pine tree state also on license plates its call ed vacationland i guess in summer been there many times in summer from ca.
As many as you pay for.