Speed limits and road signs

Speed limits

Speed limits can be an emotive subject. Excessive speed is one of the main causes of road casualties in Britain. Many people want lower speeds where they live, but some drivers still travel too fast for the conditions.

We are committed to reducing the number of people killed and injured on Oxfordshire’s roads and improving conditions for all road users, including vulnerable road users such as pedestrians and cyclists. Appropriate speed limits can help us achieve this.

The Department for Transport (DfT) sets speed limits on the national highway network in Oxfordshire, including the M40, A34 and A43. It also sets the ‘default’ speed limits that apply to most roads: 70mph on dual carriageways, 60mph on single carriageways and 30mph where street lighting is provided. The DfT also issues general advice on setting speed limits on other roads.

We are responsible for setting the limits on all other roads in the county.

How speed limits are introduced

A Traffic Regulation Order is needed to set a speed limit that differs from the default limit. This includes 30mph limits where there is no street lighting and limits above 30mph where street lighting is provided. Before making a Traffic Regulation Order, we consult widely to understand whether the proposed limit has overall support from the local community and key stakeholders.

Once a speed limit is approved, signs must be provided to show where the limit starts and ends. In most cases, additional ‘repeater’ signs are also required within the speed limit area.

Reviews

Speed limits are regularly reviewed to take account of changes in road use and the surrounding environment. This often happens as part of approved development, or through the County Council’s wider policies, including the Local Transport and Connectivity Plan and the Vision Zero road safety targets.

The 20mph Transformation Programme is now largely complete. In response to requests from parish and town councils, it has introduced 20mph speed limits in nearly 300 communities across the county.

Under the Vision Zero programme, we are also carrying out a comprehensive review of speed limits on the rural A and B road network, including some busier unnumbered roads. Any changes approved following public consultation are expected to be implemented in 2027.

Appropriate speed limits

• 20mph limits are the norm for towns and villages.
• 30mph limits may be appropriate on some town and village roads away from areas with higher pedestrian and cycle use.
• 40mph and 50mph limits are mainly used on lower-standard rural roads and on the edges of towns and villages where there are separate footways, cycle tracks and crossings.

Requesting a speed limit change

If you would like to request a change to the speed limit, please contact your town or parish council. They may already have requested a change or be able to make one on your behalf. You can also contact Highway Enquiries, and we will assess the request.

Vehicle Activated Signs and Speed Indication Devices

Vehicle Activated Signs (VAS) and Speed Indication Devices (SIDs) are electronic signs that either display the speed limit, show the speed of an approaching vehicle, or warn drivers of an approaching hazard. They are not enforcement devices, but they can help improve compliance with speed limits and raise awareness of hazards. 

Many parish and town councils have funded their own VAS and SIDs, with the County Council’s Traffic and Road Safety Team providing advice on their location and power supply.