Speed Limit sign
What does it mean?
A SPEED LIMIT sign displays the maximum posted speed for the traffic to which it applies. Conditions can require a lower speed, so the number is not a target that must be maintained in rain, darkness or congestion.
What to do when you see it
- Read the actual posted number and any vehicle or time restrictions.
- Reduce speed when visibility, traction or traffic makes the posted maximum unsafe.
- Check for a new limit as the road environment changes.
How to recognize it
- Upright white rectangle with a black border.
- SPEED LIMIT above a large black number.
- The example shows 50; other posted limits vary.
On the road
The white sign shows 50, but heavy rain reduces how far you can see. Choose a lower speed that gives you time and distance to respond.
Don’t confuse it with
Advisory speed plaque
A yellow advisory-speed plaque accompanies a warning; the white SPEED LIMIT sign states a regulatory maximum.
U.S. Route sign
A route shield's number identifies the highway, not its speed limit.
Put the meaning into practice
The related quiz includes this sign and other study questions. State practice can also cover local rules; it is not an official DMV exam.
Common U.S. sign recognition, reviewed October 3, 2026. Actual sign values, additional plaques and local rules can change how you should respond.