Most conversations about parking start at the moment a car stops. The signage, the barrier, the camera, the appeal. Almost none of them start where the driver’s experience actually begins, which is several minutes earlier, at the point they start looking.
That search is the part of parking nobody designs for, and it is the part with an environmental cost attached. A car that is circling is still using energy, still occupying road space, and still adding to the queue behind it. For anyone responsible for a site, that has a practical consequence: how easy your car park is to find and use is not only a customer-experience question, it is an emissions question too.
What the UK evidence actually says
The most widely cited UK-specific figure comes from survey research published by the traffic data firm INRIX in 2017, based on responses from 7,035 drivers across ten UK cities. Drivers surveyed reported spending an average of 44 hours a year searching for parking, with wide variation by city: London drivers averaged 67 hours, Belfast 56, Leeds 47, and Southampton 35 (INRIX, July 2017).
The same research found something that matters to landowners and property managers just as much as the time figure: 40% of drivers surveyed said they had avoided driving to shops because of problems finding parking (INRIX, July 2017). Self-reported avoidance is not the same as measured lost footfall, but it is a signal worth taking seriously: difficulty finding a space may lose you not only the patience of the people who turn up, but some of the people who never set off.
A note on that 44 hours. It is now several years old, it comes from a commercial data provider rather than a public body, and it is a survey-based average across ten cities rather than a national measurement. It is the most substantial UK-specific figure we are aware of, and we use it as an indication of scale rather than a precise national statistic.
The “30% of traffic” claim, and what it actually means
If you read much about this subject you will meet the claim that around 30% of urban traffic is circling for parking. It is worth being careful with it, because it is one of the most consistently misquoted numbers in transport.
The figure comes from the late American academic Donald Shoup, who reviewed sixteen studies conducted between 1927 and 2001 and found that, on average, 30% of the cars in congested downtown traffic were cruising for parking. The qualification matters: those studies were carried out in specific city-centre locations, at specific times, and chosen precisely because kerbside parking there was heavily oversubscribed. Across the studies that measured the share directly, the results ranged from 8% to 74% (Shoup, Cruising for parking, Transport Policy, 2006; see also Transfers Magazine, UCLA Institute of Transportation Studies).
Two things follow. First, none of those underlying studies were carried out in the UK, and the figure is routinely repeated as though it described a British city centre. It does not. Second, the claim has drifted in retelling from a finding about cars in congested city-centre traffic, in places chosen for being heavily oversubscribed, into the much broader and unsupported “30% of city congestion is caused by parking” (Paul Barter, Reinventing Parking).
We mention it because you are likely to meet it, in press coverage, in industry commentary and in reports on parking. The honest position is that circling is a real and well-documented phenomenon, that its scale varies enormously by location, and that we are not aware of a reliable UK-wide figure for it.
Where the emissions question sits
What we can say with confidence is how significant road transport is in the UK’s emissions picture. Domestic transport has been the sector with the highest greenhouse gas emissions in the UK since 2014, accounting for 29% of all UK domestic emissions in 2023. Within that, cars and taxis accounted for 54% of domestic transport emissions (Department for Transport, Transport and environment statistics).
We are deliberately not going to multiply those figures together to produce a headline number for “emissions caused by parking search”. Doing so would require assumptions nobody has properly tested in a UK context, and the result would look far more precise than the underlying evidence supports. What the numbers support is a directional statement, not an arithmetic one: cars are the dominant source of UK transport emissions, and low-speed stop-start driving is generally less efficient than steady running. Reducing avoidable search time is a plausible improvement on those grounds. We are not going to tell you how much difference it makes, because we do not think anyone credibly can.
What cars actually do most of the time
Research for the RAC Foundation found that the average car is parked at home 80% of the time, parked elsewhere 16% of the time, and actually moving only 4% of the time (Bates and Leibling, Spaced Out, RAC Foundation, July 2012). That work dates from 2012 and the underlying travel data is older still, so treat the split as a stable order of magnitude rather than a current measurement.
A car is, overwhelmingly, a parked object. Parking is not a footnote to driving, it is what cars mostly do. That reframes the question for anyone who owns or manages a site: your car park is not overflow infrastructure at the edge of the property. For most of the time your visitors are on your site, it is where their car is.
What this means if you run a site
None of this is an argument for any particular product. It is an argument for the arrangement being deliberate rather than inherited, and the natural moment to make it deliberate is the six months before your current contract ends.
Search time on a specific site is usually a design problem before it is a technology problem. It comes from signage that tells people a car park exists but not whether it has space, from layouts that force a full circuit to discover a row is full, from entrances that are hard to spot at the speed people approach them, and from capacity that works on a Tuesday and fails on a Saturday. Some of that is solved with better wayfinding and marking. Some of it is solved with occupancy monitoring or clearer real-time information. Some of it is not a parking problem at all, and the right answer is to leave it alone.
The point is that these are answerable questions, and answering them well tends to improve several things at once: fewer frustrated visitors, the potential for less circling and less avoidable emission, and a site that feels well-run to the people using it.
If you would like a straight view of how your site performs on this, a free site review is half an hour, and these are the kinds of questions it starts from. No fee, no obligation, and if the answer is that your arrangement is already working, that is what we will tell you.
Sources
- INRIX, UK parking research (press release), 12 July 2017. Survey of 7,035 UK drivers across ten cities. https://inrix.com/press-releases/parking-pain-uk/
- Donald C. Shoup, Cruising for parking, Transport Policy, volume 13, issue 6 (2006), pages 479 to 486. Review of sixteen studies, 1927 to 2001. Non-UK data. https://ideas.repec.org/a/eee/trapol/v13y2006i6p479-486.html
- Hampshire and Shoup, How Much Traffic is Cruising for Parking?, Transfers Magazine, UCLA Institute of Transportation Studies. https://transfersmagazine.org/magazine-article/issue-4/how-much-traffic-is-cruising-for-parking/
- Paul Barter, Is 30% of traffic actually searching for parking?, Reinventing Parking, October 2013. Analysis of how the figure is commonly misused. https://www.reinventingparking.org/2013/10/is-30-of-traffic-actually-searching-for.html
- Department for Transport, Transport and environment statistics: greenhouse gas emissions from transport (2023 data). https://www.gov.uk/government/statistics/transport-and-environment-statistics-2023—2/greenhouse-gas-emissions-from-transport-in-2023
- John Bates and David Leibling, Spaced Out: Perspectives on parking policy, RAC Foundation, July 2012. https://www.racfoundation.org/assets/rac_foundation/content/downloadables/spaced_out-bates_leibling-jul12.pdf
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