A-road

A320 traffic and collisions

The A320 is an A-road of 16.5 miles, in Surrey. This page covers its traffic at 18 DfT count points since 2000 and the collisions police recorded on it.

Last updated
Records analysed
18 count points in 2025
Methodology
View methodology
  • Traffic in 2025 114m vehicle miles
  • Average daily traffic 18,861 vehicles a day, both directions
  • Busiest section 33,567 A317 to A319
  • HGV share 2.2% of vehicle miles
  • Traffic since 2019 −5.0% same count points
  • Collisions, 2021 to 2025 292 51.3 per 100m vehicle miles

How busy is the A320?

On an average day in 2025, 18,861 vehicles passed each point on the A320, counting both directions. The busiest section is A317 to A319 (Surrey), with 33,567 a day; the quietest listed is A25 to A246, with 12,893.

Busiest sections, 2025

A317 to A319 carries 1.8 times the road’s average flow.

Sections of the A320 with the highest average daily flow, 2025
Section Vehicles a day
A317 to A319 Surrey · 0.6 mi · HGVs 2.4% 33,567
A319 to A245 Surrey · 2.4 mi · HGVs 2.7% 21,987
At A317 Surrey · 1.5 mi · HGVs 2.6% 20,433
A308 to Norlands Lane Surrey · 1.6 mi · HGVs 1.0% 17,449
A324 to A247 Surrey · 0.7 mi · HGVs 1.5% 17,068
A3 Slip Road, Guildford to A247 Wych Hill Lane Surrey · 4.7 mi · HGVs 2.0% 16,492
Norlands Lane to B375 St Ann's Rd Surrey · 1.2 mi · HGVs 0.8% 15,154
A245 to A3046 Surrey · 1.0 mi · HGVs 1.9% 13,970
A25 to A246 Surrey · 0.6 mi · HGVs 1.7% 12,893

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

Route

In Surrey · 16.5 miles

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

A320 traffic and collisions by section

16 sections between junctions, in route order. Each is the average of its DfT count points, weighted by length. 2 short link roads and spurs (0.8 miles) count in the road’s totals but are not listed.

Show all 16 sections Tap a column heading to sort
Sections of the A320 in route order, 2025 traffic
#
1A308 to Norlands LaneSurrey1.617,4491.0%+13.7%1842.2
2Norlands Lane to B375 St Ann's RdSurrey1.215,1540.8%+8.6%9
3B375 St Ann's Rd to B388Surrey0.216,1751.5%−6.6%fewer than 3
4B388 to A317Surrey0.416,0151.5%−6.6%7
5At A317Surrey1.520,4332.6%−9.9%2138.4
6A317 to A319Surrey0.633,5672.4%−2.8%1234.6
7A319 to A245Surrey2.421,9872.7%−4.3%3336.4
8A245 to A3046Surrey1.013,9701.9%−15.1%1556.8
9A3046 to A324Surrey0.225,6831.8%+0.7%6
10A324 to A247Surrey0.717,0681.5%−1.2%28132.5
11At A247Surrey0.214,9041.5%+5.0%6
12A3 Slip Road, Guildford to A247 Wych Hill LaneSurrey4.716,4922.0%6256.3
13A320 spur roundabout to A3Surrey0.131,4723.1%−15.2%fewer than 3
14A3 to A25Surrey0.131,4723.1%−15.2%4
15A25 to A246Surrey0.612,8931.7%−5.8%17124.3
16A246 to High StSurrey0.23,2461.2%−17.5%fewer than 3

Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the A320 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.

A320 traffic by vehicle type

Cars and taxis make up 83.8% of the vehicle miles on the A320. HGVs account for 2.2%.

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 A320, by year
Year HGV share
2000 3.8%
2001 3.4%
2002 3.4%
2003 3.3%
2004 3.3%
2005 3.2%
2006 3.2%
2007 2.9%
2008 3.0%
2009 2.8%
2010 2.7%
2011 2.8%
2012 2.6%
2013 2.7%
2014 2.6%
2015 2.6%
2016 2.7%
2017 2.7%
2018 2.6%
2019 2.5%
2020 3.0%
2021 2.8%
2022 2.6%
2023 2.4%
2024 2.3%
2025 2.2%

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

A320 traffic trend

Traffic on the A320 came to 114 million vehicle miles in 2025. At the count points present in both years, it is down 5.0% on 2019, before the pandemic, and down 7.4% on 2015.

Vehicle miles a year

Like for like, traffic is down 0.8% on 2000.

Vehicle miles on the A320 each year, the whole road as it was that year
Year Vehicle miles
2000 111m
2001 111m
2002 114m
2003 112m
2004 114m
2005 111m
2006 111m
2007 110m
2008 109m
2009 108m
2010 110m
2011 111m
2012 110m
2013 108m
2014 111m
2015 112m
2016 114m
2017 110m
2018 108m
2019 126m
2020 96m
2021 107m
2022 118m
2023 121m
2024 111m
2025 114m

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

Average daily flow

Average daily flow along the A320, weighted by link length, by year
Year Vehicles a day
2000 19,621
2001 19,591
2002 20,211
2003 19,794
2004 20,142
2005 19,528
2006 19,614
2007 19,418
2008 19,201
2009 19,069
2010 19,419
2011 19,642
2012 19,379
2013 19,013
2014 19,567
2015 19,852
2016 20,215
2017 19,405
2018 18,942
2019 20,226
2020 15,320
2021 17,131
2022 18,499
2023 18,996
2024 18,349
2025 18,861

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 (71.5% of today’s road for 2019). In 2025, 6 of the 18 count points were counted; DfT estimated the rest from earlier counts and local trends.

A320 collisions

Police recorded 292 collisions with the A320 as the first road from 2021 to 2025, 66 of them fatal or serious. That is 51.3 per 100 million vehicle miles, higher than the 31.5 for all A-roads in Great Britain. On average there were 3.5 a year for each mile of road.

Reported collisions by year

Down 17.2% from 2021 to 2025.

Police-reported collisions on the A320 by year: fatal or serious, and slight
Year SlightFatal or serious
2021 4414
2022 4710
2023 5412
2024 4419
2025 3711

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 A320, 2021 to 2025
Section Per 100m vehicle miles
A324 to A247 Surrey · 28 collisions 132.5
A25 to A246 Surrey · 17 collisions 124.3
A245 to A3046 Surrey · 15 collisions 56.8
A3 Slip Road, Guildford to A247 Wych Hill Lane Surrey · 62 collisions 56.3
A308 to Norlands Lane Surrey · 18 collisions 42.2
At A317 Surrey · 21 collisions 38.4
A319 to A245 Surrey · 33 collisions 36.4
A317 to A319 Surrey · 12 collisions 34.6

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

A further 29 collisions were recorded at junctions where the A320 was the second road; they are not in the figures above. Fatal or serious uses DfT’s adjusted serious figures. How we count collisions

Council areas on the A320

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 18 count points in 2025 15 September 2026
Reported collisions Road safety open data (STATS19) Department for Transport
Derived statistics UK Motoring
2021 to 2025 292 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.