Minimum speed limit of 30 miles per hour

Speed limit signs

Minimum speed limit of 30 miles per hour

30 mph minimum speed limit – you must not go slower than 30 mph (unless conditions make it unsafe). This sign is common in tunnels and certain motorway slip roads. In the theory test it tests your understanding of minimum speed limits and the need to maintain speed. Always keep to at least 30 mph unless it is unsafe to do so.

Shape
Circular
Background
Blue
Border
White
Text type
Number (Other)
Diagram reference
672.0

Where you'll see this sign

Tunnels and certain motorway slip roads.

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