The Complete Guide to UK Speed Limits
UK speed limits are set by law. The defaults are 30 mph in lit areas, 60 mph on single carriageways, and 70 mph on motorways and dual carriageways — unless signs show otherwise. Lower limits apply when towing a caravan or trailer.
Speed limits in the UK are not complicated, but they are frequently misunderstood — particularly where default limits apply without signage, or where different rules apply to different vehicle types. This guide covers everything a car driver needs to know.
What are the speed limits in the UK?
UK speed limits are set under the Road Traffic Regulation Act 1984. The most important thing to understand is that limits are set by road type and environment — and many roads carry a default limit that applies even when no signs are posted.
| Road type | Default limit | How it is indicated |
|---|---|---|
| Built-up area (street lighting present) | 30 mph | Street lighting — no signs required |
| Single carriageway outside built-up area | 60 mph | National speed limit sign (white circle, diagonal stripe) |
| Dual carriageway | 70 mph | National speed limit sign |
| Motorway | 70 mph | National speed limit sign, or digital gantry signs |
Local authorities may set lower limits — 20 mph zones are increasingly common in towns and cities, and 40 or 50 mph limits are often applied on faster A-roads passing through semi-rural areas. These are always indicated by signs.
How do you know what speed limit you're on?
The limit is shown by a sign at the point where it begins. After the entry sign, repeater signs on both sides of the road confirm the limit continues.
- 30 mph in a lit area: no signs required if street lighting is present with posts no more than 200 metres apart. If lighting is present and no repeater signs are visible, 30 mph applies.
- National speed limit: the white circular sign with a diagonal black line means the national limit applies for that road type (60 on a single carriageway, 70 on a dual or motorway). It does not mean 70 on all roads.
- Posted limits: a number in a red circle (e.g. 40, 50, 20) indicates a limit that overrides the default for that road.
💡 Key point: A road with street lighting but no posted signs defaults to 30 mph — not 60 mph. Many drivers are surprised to receive a NIP on a lit road they believed was a 60 mph route.
Why do speed limits change on the same road?
A single A-road can move through multiple speed limit zones as it passes through towns, villages, school areas, and rural stretches. Each zone change is signposted, but transitions are easy to miss — especially on familiar routes where drivers navigate from memory rather than observation.
This is one of the most common causes of unintentional speeding. Read more: why drivers speed without realising.
Do speed limits differ for different vehicles?
Yes. The standard limits above apply to cars, motorcycles, and light goods vehicles up to 3.5 tonnes unladen. Different — and almost always lower — limits apply to larger vehicles, and to cars when towing.
Speed limits when towing a caravan or trailer
If you are towing with a car, the following limits replace the standard national limits. The 30 mph limit in built-up areas is the same.
| Vehicle type | Built-up area | Single carriageway | Dual carriageway | Motorway |
|---|---|---|---|---|
| Car / motorcycle | 30 mph | 60 mph | 70 mph | 70 mph |
| Car towing caravan or trailer | 30 mph | 50 mph | 60 mph | 60 mph |
| Goods vehicle ≤7.5 tonnes | 30 mph | 50 mph | 60 mph | 70 mph |
| Goods vehicle >7.5 tonnes | 30 mph | 50 mph | 60 mph | 60 mph |
| Minibus (9–16 passengers) | 30 mph | 50 mph | 60 mph | 70 mph |
⚠️ Note: Speed Angel is designed for car drivers. The limits above for goods vehicles and minibuses are provided for general awareness. The app does not detect vehicle type or automatically apply towing limits — if you are towing, you are responsible for observing the lower limits that apply.
What happens if you exceed the speed limit?
Speeding is a criminal offence in the UK under the Road Traffic Regulation Act 1984. The consequences range from a fixed penalty notice to a court appearance and potential disqualification.
- Fixed Penalty Notice (FPN): £100 fine and 3 penalty points — offered for most first-time or moderately over-limit offences
- Speed awareness course: offered instead of points if you have not attended one in the past 3 years and were not excessively over the limit
- Court summons: for speeds significantly above the limit (typically 50%+ over) — fines up to £1,000 on most roads (£2,500 on motorways), 4–6 points, or disqualification
- New drivers: 6 points within 2 years of passing your test results in automatic revocation — you must retake both theory and practical tests
For more detail on enforcement and how fines are calculated: how to avoid a speeding fine.
Why drivers speed unintentionally — and how to avoid it
Most speeding on UK roads is not deliberate. Research and accident data consistently point to the same root causes: speed limit transitions that happen faster than a driver notices, speed creep on motorways where the effort of maintaining speed is imperceptible, and the natural tendency to over-estimate how slowly you are travelling after time at higher speeds.
Speedometers also systematically over-read — most show 2–5 mph more than your actual speed. If your dial shows 34 mph, you are likely travelling at 30–32 mph actual. Speed cameras use their own calibrated equipment, not your vehicle's instruments. GPS apps give a useful reference but are subject to signal conditions — neither is a certified measurement, and neither is a legal defence against a speeding allegation.
GPS-based speed measurement is accurate in a way a mechanical speedometer is not. Speed cameras, and speed limit apps, use GPS-derived speed.
Read more: the psychology of unintentional speeding.
Tools that support speed limit awareness
GPS navigation devices (sat navs) often display a speed limit indicator, though coverage and accuracy vary. Dedicated speed limit awareness apps tend to offer more precise, heading-aware data.
Tools designed for speed limit compliance — rather than camera avoidance — work differently from camera warning systems. Instead of alerting only near known enforcement points, they provide continuous real-time feedback on the current posted limit, regardless of camera locations. This supports consistent compliance rather than situational compliance.
For an analysis of camera detectors specifically, see: speed camera detectors: do they really help?
Speed Angel is a speed limit awareness app for Android, designed specifically for UK roads. It displays the legal limit for the road you are on and alerts you the moment your GPS speed exceeds it — with a configurable tolerance and alert style. It runs in the background alongside any navigation app.
Frequently asked questions
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Both — it depends on the road type. The national speed limit is 70 mph on motorways and dual carriageways, and 60 mph on single-carriageway roads outside built-up areas. The national speed limit sign (white circle with a diagonal black stripe) means the appropriate national limit applies for the road you are on — it does not always mean 70 mph.
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When towing, cars are limited to 50 mph on single carriageways and 60 mph on dual carriageways and motorways. The 30 mph limit in built-up areas is unchanged. These lower limits apply even where a higher limit is posted — posted limits set the maximum, and towing rules apply a further restriction below that.
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Yes. Speed limits can change multiple times on the same road, particularly on A-roads that pass through towns and villages. The current limit is shown by a sign at the point of change and by repeater signs along the zone. In the absence of repeater signs on a lit road, assume 30 mph applies.
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A fixed penalty notice (FPN) is the standard penalty for most speeding offences: a £100 fine and 3 penalty points on your licence. You may be offered a speed awareness course as an alternative if you have not attended one in the past 3 years. More serious speeding is referred to court where fines can reach £1,000 (or £2,500 on motorways) and disqualification is possible.
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Yes. Speed limit awareness apps are entirely legal. They use GPS and publicly available road data to display the current posted limit and alert drivers when they exceed it. They do not emit or detect radar signals. They are a legitimate driving aid, similar in concept to a GPS navigation device showing speed limit data.
Know your limit on every road
Speed Angel shows the current posted speed limit in real time and alerts you the moment you exceed it — across UK roads. Free 14-day trial on Android, no restrictions.
▶ Download Speed Angel FreeDisclaimer: This guide is for general information only. Speed limits and enforcement rules are subject to change. Always observe posted signs, which take precedence over any database or app. Speed Angel is a driving awareness aid — it does not replace your legal obligation to observe the speed limit.