Glasgow 20mph Citywide Speed Limit - Frequently Asked Questions

The speed limit on the majority of Glasgow streets is set to be lowered to 20mph.

The proposed changes, which follow an in-depth analysis of the city's road network, supports the Scottish Government's National Strategy for 20mph which will see the rollout of this safer speed limit in built up areas across Scotland.

With 340km of streets including Glasgow city centre already assigned a 20mph limit, a wider lowering of vehicle speeds is expected to make our roads safer and encourage more walking, wheeling and cycling in quieter and less congested neighbourhoods.

Why 20mph?

Quite simply, slower is safer.

The evidence shows that if you hit a pedestrian at 30mph, they are seven times more likely to die than at 20mph. 

In 2020, the council approved plans that would see a mandatory 20mph speed limit become the standard for all residential streets, the city centre, other main shopping areas or where there are high levels of walking, wheeling or cycling. Other streets in the city would generally remain at 30mph.

The move to a reduced 20mph speed limit on residential roads is a key component of the council's  Road Safety Plan (PDF) [14MB] (opens new window) which sets a target of zero fatalities or serious injuries on city roads by 2030. It also ties in with Glasgow's Transport Strategy which supports road safety and active travel, as well as creating people-friendly public spaces and transport decarbonisation.

Where will the 20mph speed limit apply?

Following an individual analysis of 5,740 Glasgow streets with a 20mph or 30mph speed limit, it is proposed that:

• 3,868 streets currently assigned a 30mph speed limit should be reduced to 20mph.
• 1,400 streets currently assigned a 20mph speed limit should all remain at 20mph.
• 472 streets currently assigned a 30mph speed limit should remain at 30mph.

All other streets assigned a 40mph speed limit or above will be unaffected.

An interactive mapping tool which highlights the existing and proposed speed limits across the city is available by clicking on this weblink.

How were streets identified for 20mph?

The analysis of streets with a 20mph or 30mph speed limit was based on guidance and criteria produced by Transport Scotland. This guidance looks at various factors including whether there are schools, shops, community facilities or health settings in the vicinity which would suggest a greater level of vulnerable road users will likely be present.

Have all 30mph roads changed to 20mph?

The rollout of lower 20mph speed limits focuses on built up areas. There are however routes within the city that lend themselves to remaining at 30mph where reasonable and practicable.

Based on an assessment to national guidelines, 472 streets currently assigned a 30mph speed limit are proposed to remain at 30mph.

An interactive mapping tool which highlights the proposed speed limits across the city is available by clicking on this weblink.

Will speed cushions be installed on 20mph streets?

Almost all streets lowered to a 20mph speed limit will not require physical calming measures. This is because revised legislation and guidance means that widespread restrictions can be introduced without the construction of measures such as speed cushions.

On those roads where evidence suggests wider speed management measures would be beneficial, these will be introduced, however most streets will adopt a signage and road markings approach like we have in our city centre, and as used widely by other councils.

When will the wider 20mph speed limits be introduced?

The implementation of 20mph speed limits in Glasgow will be phased in on a zonal basis - each requiring the promotion of a Speed Limit Order. This follows a statutory process which generally takes 12 to 18 months to complete and includes a formal consultation phase.

The extent of the zone areas and a delivery timetable will be finalised following completion of the technical design work. This will look at signage requirements and any additional speed restriction measures that might be necessary.

How will I know I am entering/exiting a 20mph speed limit area?

	A sign as shown on each side of the road will mark the start of the zone.
	A sign as shown on each side of the road will mark the end of the zone.

Will journeys take longer?

An evaluation by the Department for Transport into the effectiveness of sign only 20mph limits shows that journey times are estimated to have increased by 3% in residential areas and 5% in city centre areas, based on the observed change in median speed (from GPS journey speed data). This adds less than half a minute to a two-mile trip and less than a minute to a five-mile trip.

It is anticipated that any adverse impacts would be minimal. Most roads suitable for 20 mph will exclude strategic routes, and the roads affected will typically be the start or the end of most journeys, and not affecting the main part of the trip. 

Will air quality be affected?

Imperial College, London found that 20mph limited areas were pollution neutral.

Slower vehicles and quieter streets will also encourage more walking, wheeling and cycling, because people feel safer. This will mean fewer car journeys which will contribute to ongoing improvements to the city's air quality.

How can 20mph speed limits encourage more active travel?

Vehicle speeds are one of the key reasons why people do not walk, wheel or cycle.

By increasing the perception of feeling safe, people become more comfortable travelling actively. A wider, lowering of the speed limit to 20mph therefore has the potential to encourage more walking, wheeling and cycling and fewer car journeys.

What are the safety benefits from lowering speeds?

Slower is safer. If you hit someone at 30mph, they're seven times more likely to die than at 20mph.

There are many other reasons why lowering the speed limit from 30mph to 20mph is beneficial - these include:

• A reduction in the severity of, and total number of road collisions.
• Creating safer spaces for all road users to enjoy.
• Encouraging a change in the way we travel for those shorter, everyday journeys to promote healthier lifestyles.
• Improving our communities, by lowering vehicle speeds in the places we live and visit.

How will 20mph speed limits by enforced?

Enforcement of speed limits on all roads is a matter for Police Scotland.

It is hoped that people will understand and appreciate the benefits that driving at a lower speed can offer and so will make a positive decision to keep to the new limit.

Police Scotland is supportive of improved road safety across the city and is working with the council to achieve this.

Will the new 20mph speed limits be permanent?

The new, lower 20mph speed limits will be made permanent following the consultation and promotion of the new Speed Limit Orders.

Once implemented, and with a consideration of local needs, we will monitor and assess their effectiveness to determine whether the speed limit should remain at 20mph.