Trunk A-road

A3100 traffic and collisions

The A3100 is a trunk A-road of 9.2 miles, in Surrey. This page covers its traffic at 12 DfT count points since 2000 and the collisions police recorded on it.

Last updated
Records analysed
12 count points in 2025
Methodology
View methodology
  • Traffic in 2025 50m vehicle miles
  • Average daily traffic 14,779 vehicles a day, both directions
  • Busiest section 19,826 A3100 London Rd to A3
  • HGV share 0.9% of vehicle miles
  • Traffic since 2019 −5.8% same count points
  • Collisions, 2021 to 2025 124 51.4 per 100m vehicle miles

How busy is the A3100?

On an average day in 2025, 14,779 vehicles passed each point on the A3100, counting both directions. The busiest section is A3100 London Rd to A3 (Surrey), with 19,826 a day; the quietest listed is A25 to A246, with 10,419.

Busiest sections, 2025

A3100 London Rd to A3 carries 1.3 times the road’s average flow.

Sections of the A3100 with the highest average daily flow, 2025
Section Vehicles a day
A3100 London Rd to A3 Surrey · 0.5 mi · HGVs 0.5% 19,826
Primrose Ridge to Wey Court Surrey · 2.2 mi · HGVs 0.8% 17,628
A248 to Wey Court, Godalming Surrey · 1.4 mi · HGVs 1.0% 16,578
Primrose Ridge, Godalming to A286 Surrey · 0.5 mi · HGVs 0.8% 16,041
A3100 Clay Lane to A25 Surrey · 0.9 mi · HGVs 0.9% 15,593
Sandy Lane, Guildford to A248 Surrey · 1.2 mi · HGVs 1.1% 13,086
Sandy Lane to A31/A281 Surrey · 0.7 mi · HGVs 1.4% 12,933
A25 to A246 Surrey · 0.8 mi · HGVs 0.6% 10,419

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

Route

In Surrey · 9.2 miles

Surrey
Schematic route: each line joins the junctions at the ends of a DfT count point link.

A3100 traffic and collisions by section

11 sections between junctions, in route order. Each is the average of its DfT count points, weighted by length. 1 short link roads and spurs (0.2 miles) count in the road’s totals but are not listed.

Sections Tap a column heading to sort
Sections of the A3100 in route order, 2025 traffic
#
1A3100 London Rd to A3Surrey0.519,8260.5%−6.8%5
2A3100 Clay Lane to A25Surrey0.915,5930.9%−6.2%2184.6
3A25 to A246Surrey0.810,4190.6%−0.3%1284.4
4High St to York RdSurrey0.27,5110.5%−6.2%10
5Chertsey St to A25Surrey0.26,5320.6%−6.9%3
6Sandy Lane to A31/A281Surrey0.712,9331.4%−6.2%1062.5
7Sandy Lane, Guildford to A248Surrey1.213,0861.1%+3.5%6
8A248 to Wey Court, GodalmingSurrey1.416,5781.0%−0.8%1947.9
9Primrose Ridge to Wey CourtSurrey2.217,6280.8%−10.9%2737.7
10Primrose Ridge, Godalming to A286Surrey0.516,0410.8%−10.9%4
11A286 to A283Surrey0.410,0172.4%−6.6%5

Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the A3100 as the first road, placed on the nearest section by their recorded position; rates (per 100 million vehicle miles) are shown for sections of half a mile or more with 10 or more.

A3100 traffic by vehicle type

Cars and taxis make up 86.6% of the vehicle miles on the A3100. HGVs account for 0.9%.

Vehicle mix, 2025

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

HGV share of traffic

HGVs as a share of vehicle miles on the A3100, by year
Year HGV share
2000 1.9%
2001 2.0%
2002 2.1%
2003 2.3%
2004 2.4%
2005 2.0%
2006 1.7%
2007 1.9%
2008 1.6%
2009 1.3%
2010 1.2%
2011 1.3%
2012 1.3%
2013 1.3%
2014 1.2%
2015 1.2%
2016 1.1%
2017 1.1%
2018 1.2%
2019 1.1%
2020 1.3%
2021 1.3%
2022 1.2%
2023 1.1%
2024 1.0%
2025 0.9%

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

A3100 traffic trend

Traffic on the A3100 came to 49.6 million vehicle miles in 2025. At the count points present in both years, it is down 5.8% on 2019, before the pandemic, and down 8.0% on 2015.

Vehicle miles a year

Like for like, traffic is down 13.2% on 2000.

Vehicle miles on the A3100 each year, the whole road as it was that year
Year Vehicle miles
2000 59m
2001 58m
2002 59m
2003 58m
2004 59m
2005 58m
2006 57m
2007 57m
2008 54m
2009 54m
2010 54m
2011 54m
2012 54m
2013 53m
2014 54m
2015 54m
2016 55m
2017 53m
2018 53m
2019 53m
2020 40m
2021 44m
2022 48m
2023 49m
2024 50m
2025 50m

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

Average daily flow

Average daily flow along the A3100, weighted by link length, by year
Year Vehicles a day
2000 15,950
2001 15,630
2002 15,870
2003 15,834
2004 15,959
2005 15,853
2006 15,439
2007 15,313
2008 14,569
2009 14,755
2010 14,526
2011 14,672
2012 14,535
2013 14,346
2014 14,758
2015 15,218
2016 14,818
2017 14,804
2018 14,775
2019 15,693
2020 12,012
2021 13,212
2022 14,341
2023 14,598
2024 14,971
2025 14,779

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

The chart counts the whole road as it was each year, so new or renumbered stretches move it. The percentage changes compare only count points present in both years. In 2025, 1 of the 12 count points were counted; DfT estimated the rest from earlier counts and local trends.

A3100 collisions

Police recorded 124 collisions with the A3100 as the first road from 2021 to 2025, 22 of them fatal or serious. That is 51.4 per 100 million vehicle miles, higher than the 31.5 for all A-roads in Great Britain. On average there were 2.7 a year for each mile of road.

Reported collisions by year

About the same in 2025 as in 2021.

Police-reported collisions on the A3100 by year: fatal or serious, and slight
Year SlightFatal or serious
2021 213
2022 333
2023 206
2024 113
2025 177

Source:DfT STATS19,UK Motoring analysis 2021 to 2025 Updated

Sections with the highest collision rates

Per 100 million vehicle miles, 2021 to 2025. Sections of half a mile or more with 10 or more collisions.

Collisions per 100 million vehicle miles by section of the A3100, 2021 to 2025
Section Per 100m vehicle miles
A3100 Clay Lane to A25 Surrey · 21 collisions 84.6
A25 to A246 Surrey · 12 collisions 84.4
Sandy Lane to A31/A281 Surrey · 10 collisions 62.5
A248 to Wey Court, Godalming Surrey · 19 collisions 47.9
Primrose Ridge to Wey Court Surrey · 27 collisions 37.7

Source:DfT STATS19,UK Motoring analysis 2021 to 2025 Updated

A further 19 collisions were recorded at junctions where the A3100 was the second road; they are not in the figures above. Fatal or serious uses DfT’s adjusted serious figures. 98.4% of the collisions could be placed on a section. How we count collisions

Council areas on the A3100

In route order. Each is the highway authority DfT files the count points under.

  • Surrey

Data sources and methodology

Datasets used on this page
Figures Source Period Records Updated
Traffic counts and vehicle mix Road traffic statistics (AADF by count point) Department for Transport
Derived statistics UK Motoring
2000 to 2025 12 count points in 2025 15 September 2026
Reported collisions Road safety open data (STATS19) Department for Transport
Derived statistics UK Motoring
2021 to 2025 124 reported collisions 15 September 2026
  • Annual average daily flow (AADF) is the average number of vehicles passing a point on a typical day of the year, both directions combined.
  • Vehicle miles are AADF multiplied by link length and 365, summed over every count point link on the road.
  • Sections join count point links between junctions, using the link lines in DfT’s major road database.
  • STATS19 covers personal injury collisions reported to the police. Damage-only collisions are not included, and not every injury collision is reported.
  • Serious and slight figures are DfT’s adjusted estimates, which allow for police forces moving to injury-based reporting.
  • Counts of one or two collisions below Great Britain level are shown as “fewer than 3”.

Contains public sector information licensed under the Open Government Licence v3.0.