School speed limit sign: meaning and rules

School speed limit sign: what it means

School speed limit sign: a white vertical rectangle with a yellow-green SCHOOL header, the words SPEED LIMIT 20 and WHEN FLASHING

Drawing: Drivoku, based on MUTCD sign S5-1. Simplified; real signs follow the FHWA Standard Highway Signs specifications.

The School Speed Limit sign sets a lower speed limit near a school. On the WHEN FLASHING version, the lower limit applies while the yellow lights flash.

What does the school speed limit sign mean?

MUTCD Section 7B.05 says a School Speed Limit assembly or School Speed Limit When Flashing sign is used where a reduced school speed limit zone has been set by an engineering study or by law. A School sign is placed before it, and an END SCHOOL SPEED LIMIT or END SCHOOL ZONE sign marks the end.

Quick quiz

What does the sign at the top of this page mean?

The school zone ends here.
A lower speed limit near a school when the lights flash.
A school area, zone or crossing is near.

Show answer

B. A lower speed limit near a school when the lights flash. A reduced school speed limit applies, here while the lights flash (MUTCD Section 7B.05). Source: MUTCD 11th Edition, Part 7, Traffic Control for School Areas: Section 7B.05, FHWA; MUTCD 11th Edition, FHWA

Where will you see it?

At the start of school speed zones, near school entrances and crossings.

What should you do?

Slow down to the school limit while it applies and keep to it until the end sign. Watch for children, crossing guards and buses.

What do people get wrong?

Speeding up again before the end-of-zone sign. The lower limit lasts until the END SCHOOL SPEED LIMIT or END SCHOOL ZONE sign.

Common questions

When does a school speed limit apply?

On a WHEN FLASHING sign, while the lights flash. Other school speed limit assemblies use plaques with times or conditions (MUTCD Section 7B.05).

Where does the school zone end?

At an END SCHOOL SPEED LIMIT or END SCHOOL ZONE sign (Section 7B.05).

Compare with

Want to test someone else? Play a road-sign quiz with friends and family.

Sources

Checked on 3 November 2026 against the MUTCD 11th Edition (FHWA), Section 7B.05.

MUTCD 11th Edition, Part 7, Traffic Control for School Areas: Section 7B.05, FHWA
MUTCD 11th Edition, FHWA. FHWA lists the current version as the 11th Edition with Revision 1, dated December 2025

Sign pictures are our own simplified drawings of the MUTCD designs, which are in the public domain (MUTCD Section 1D.06). Sources and image credits.