Regulatory signs
Do Not Pass sign
You may not pass another vehicle here, no matter what the pavement markings show.
- Tall rectangle
- White
- MUTCD R4-1
Shape and background first
Federal designation R4-1 in the MUTCD, the national standard every state signs to. Posted at the exact point a no passing zone begins, usually right where the centerline changes from broken to solid yellow.
What the MUTCD specifies
Designation: R4-1
MUTCD Section 2B.36
Conventional road size: 24 x 30 in
Option: A DO NOT PASS sign may reinforce pavement markings where passing is restricted.
Source: Federal Highway Administration, MUTCD 11th Edition (December 2023), Part 2, Table 2B-1; Section 2B.36, verified 2026-09-26.
What the test wants you to know
The mistake people make
This is the posted regulation, while the yellow pennant shaped No Passing Zone sign is only the advance warning that the zone is coming. If a question shows both signs, the pennant is the one drivers reach first, and this one marks where the restriction actually starts.
The sign people confuse it with
Do Not Pass gets mixed up with No Passing Zone more than any other pairing in this category. Put them side by side and the difference is obvious, which is exactly why it is worth doing once rather than meeting them cold in the exam.
Do Not Pass
You may not pass another vehicle here, no matter what the pavement markings show.
No Passing Zone
The start of a stretch where passing another vehicle is prohibited.
