20 mph: A survey of GB attitudes and behaviours

  • Published: Bristol Social Marketing Centre & University of West England, 2013
  • Authors: Tapp, A., Nancarrow, C.
  • Date Added: 05 May 2017
  • Last Update: 05 May 2017
  • Format: html


The survey had the following objectives. The authors needed to understand:

  • levels of support and opposition to 20mph speed limits.
  • the reasons for support or opposition.
  • the extent to which drivers will or will not comply with 20mph limits.
  • the effect of other motorists on respondents’ own behaviour.
  • attitudes to driving and speed limits, and how these might affect behaviour.
  • behaviour change: identifying influencers, levels of active citizenship.


Fieldwork was contracted to YouGov, a large UK provider of social and market research. The total sample size was 3,074 GB adults. The effective sample size, i.e. the sample size that is permissible for statistical tests after weighting procedures, was 2947. There were also boosters in some cities and towns with 20mph and a control set of equivalent cities and towns, reported separately.

Fieldwork was undertaken between 09/07/2013 - 22/07/2013. The survey was carried out online. One reason for opting for an online access panel was that the absence of an interviewer is thought to reduce socially desirable responding. In other words, elicit a more honest answer.

Key Findings:

  • Levels of support for 20mph. 65% of respondents’ support 20mph limits in residential areas, and 31% oppose. There is slightly more net support, at 72%, for 20mph limits on busy streets/shopping areas than the 65% for residential streets.

  • Reasons for support or opposition. When asked for reasons to support 20mph limits, perhaps not surprisingly road safety and children’s safety are where the public’s collective priority currently lies. Other reasons - such as encouraging a healthier way of life, improving traffic flows, reducing congestion - achieved much lower support. When asked for their agreement with reasons to oppose 20mph limits, a cluster of around half the population agreed that 20mph limits will be ignored, not enforced or are pointless. In summary, there seems to be a widespread feeling amongst many that 20mph limits, worthwhile in theory, would not work in practice. 39% of people also believe that 20mph limits will make journey times longer and 36% thought they would increase congestion.

  • Supporter and Opponent Profiles. Supporters of 20mph limits are more likely to be female, aged 35 or over, white, Lab/Lib-Dem/Green voters, and low-mileage drivers. In contrast, (picking out factors of particular probable importance) opponents of 20mph limits are more inclined to be high mileage driving males, drivers of commercial vehicles, and from the 16-34 age band.

  • Prevalence of 20mph limits. Currently, a fifth (20%) of the GB sample say they live on a road that has a 20mph speed limit.

  • How will people drive if 20mph limits arrive? A majority of drivers, 64%, agree that they ‘will be careful to observe new 20 mph limits wherever they are’. However, a large minority (31%) say 'If a 20mph speed limit is introduced, I may not stick to it.

  • The effect of lack of enforcement on speed limit compliance. A majority, 57%, of respondents hope the police will enforce 20mph limits but there is little belief that this will happen. A larger majority, 71%, agree that people will ignore 20mph limits because they don’t see themselves getting caught by the police. There is therefore a widespread belief that the police will not effectively enforce the limits, and that, in consequence ‘other people’ will ignore 20mph limits.

  • The effect of ‘other motorists’ on speed limit compliance. People mostly think speed limits should be obeyed, (73% agree that breaking speed limits is not acceptable in most circumstances) but there is less collective certainty that they will be obeyed (71% agreed that If 20mph limits were introduced most drivers would not stick to them). In other words the strong collective moral norm (breaking speed limits is not acceptable) is not supported by the descriptive norm (other drivers won’t obey the new limits) ...so the danger is that the reaction may very well be “no one else is, so why should I bother sticking to them”.

  • Cycling, walking and 20mph Limits. The majority of the public agree that encouraging walking (82%) and cycling (55%) for short journeys is a good idea. However, support was less marked amongst opponents of 20mph speed limits. A significant minority also agree that if traffic were slower they would walk more (20%) or cycle more (25%). Again, opponents are much less likely to agree to either.


20mph limits, Speed limit compliance, Supporter and opponent profiles.