What is the national speed limit for a car on a dual carriageway?
The national speed limit for a car on a dual carriageway is 70 mph, unless signs show a lower speed limit. A dual carriageway is identified by a central reservation separating traffic travelling in opposite directions. It is the central reservation—not the number of lanes—that makes it a dual carriageway.
Remember that 70 mph is the maximum speed limit, not a target. You must drive at a speed that is safe for the conditions. Heavy traffic, poor visibility, rain, ice or other hazards may mean that a much lower speed is appropriate.
Quick Self-Test
You are driving a car on a dual carriageway displaying the national speed limit sign. What is the maximum speed limit?
A) 50 mph
B) 60 mph
C) 70 mph
D) 80 mph