what is the national speed limit on a single carriageway

In the UK, the national speed limit on a single carriageway for standard cars and motorcycles is 60 mph (96 km/h), unless signs say otherwise.

Core rule: single carriageway national limit

• For cars, motorcycles, car-derived vans and dual-purpose vehicles , the national speed limit on a single carriageway is 60 mph.

• A single carriageway is a road where traffic in both directions is not separated by a physical central reservation.

• This 60 mph is a maximum , not a target; you must drive slower if conditions make 60 unsafe.

When the limit is lower

Some vehicles have lower national speed limits on single carriageways:

• Cars and motorcycles towing a trailer or caravan: 50 mph
• Most vans (not car‑derived): 50 mph
• Buses, coaches and minibuses : 50 mph
• Many goods vehicles (HGVs, depending on weight and country in the UK): typically 40–50 mph

Always check your vehicle class (for example, in the V5C logbook) to confirm which row of the national speed limit table applies.

Signs, streetlights and exceptions

• If there are lower posted limits (20, 30, 40 or 50 zones), those override the national limit, even on what looks like a single carriageway.

• In built‑up areas with street lighting, the default limit is usually 30 mph (or 20 mph in many parts of Wales), not 60 mph.

• Temporary signs (roadworks, school zones, variable limits) always take priority over the general national limit.

Quick forum-style takeaway

On a standard UK single carriageway with the “national speed limit” sign and no lower posted limit, a normal car or motorcycle can go up to 60 mph , but many larger or towing vehicles are capped at 50 mph or less and everyone must slow down when conditions demand it.

Information gathered from public forums or data available on the internet and portrayed here.