Speed Limit sign

What to do

Do not go faster than the posted number, and drive slower when traffic, weather, road or visibility conditions call for it.

Treat the posted number as the most you may drive in good conditions and slow down further for rain, traffic, darkness or pedestrians.

The number shown in the image is a placeholder example.

Where it's used

Section 2B.21 says Speed Limit signs show limits set by state law or established as speed zones from an engineering study, and the numbers must be in multiples of 5 mph. They should be placed at points where the limit changes and repeated beyond major intersections. Common companions are the Minimum Speed Limit (R2-4P), Night Speed Limit (R2-3P), TRUCK and WORK ZONE plaques, CITYWIDE/NEIGHBORHOOD plaques with UNLESS OTHERWISE POSTED, and a REDUCED SPEED LIMIT AHEAD (W3-5) sign before a lower zone.

Don't confuse it with

• Advisory Speed plaque: The yellow Advisory Speed plaque recommends a safe speed for a curve or hazard, while the white Speed Limit sign sets the legal maximum.
• Reduced Speed Limit Ahead: REDUCED SPEED LIMIT AHEAD is a yellow warning that a lower limit begins ahead; the white Speed Limit sign marks where the limit actually applies.
• Combined Maximum and Minimum Speed Limits: The combined sign also shows a legal minimum speed, whereas the standard Speed Limit sign shows only the maximum.