A-road

A343 traffic and collisions

The A343 is an A-road of 27.4 miles, from West Berkshire to Wiltshire. This page covers its traffic at 11 DfT count points since 2000 and the collisions police recorded on it.

Last updated
Records analysed
11 count points in 2025
Methodology
View methodology
  • Traffic in 2025 81m vehicle miles
  • Average daily traffic 8,132 vehicles a day, both directions
  • Busiest section 14,557 A303/A342 roundabout to A3057
  • HGV share 1.9% of vehicle miles
  • Traffic since 2019 −0.7% same count points
  • Collisions, 2021 to 2025 98 25.4 per 100m vehicle miles

How busy is the A343?

On an average day in 2025, 8,132 vehicles passed each point on the A343, counting both directions. The busiest section is A303/A342 roundabout to A3057 (Hampshire), with 14,557 a day; the quietest listed is B3048 to Saxon Way, Andover, with 5,011.

Busiest sections, 2025

A303/A342 roundabout to A3057 carries 1.8 times the road’s average flow.

Sections of the A343 with the highest average daily flow, 2025
Section Vehicles a day
A303/A342 roundabout to A3057 Hampshire · 2.2 mi · HGVs 0.9% 14,557
Garden Close Lane to A339 West Berkshire · 2.2 mi · HGVs 0.6% 13,023
A3057/A3093 to Saxon Way Hampshire · 1.1 mi · HGVs 1.1% 12,880
B3084 to A303 Hampshire · 5.3 mi · HGVs 3.7% 10,081
Garden Close Lane, Newbury to A34 West Berkshire, Hampshire · 0.8 mi · HGVs 0.8% 9,283
B3084 to A30 Hampshire, Wiltshire · 2.8 mi · HGVs 3.1% 7,261
A34 to B3048 Hampshire · 8.8 mi · HGVs 1.4% 5,018
B3048 to Saxon Way, Andover Hampshire · 3.9 mi · HGVs 1.5% 5,011

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

Route

West Berkshire to Wiltshire · 27.4 miles

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

A343 traffic and collisions by section

9 sections between junctions, in route order. Each is the average of its DfT count points, weighted by length.

Sections Tap a column heading to sort
Sections of the A343 in route order, 2025 traffic
#
1Garden Close Lane to A339West Berkshire2.213,0230.6%−0.7%1632.5
2Garden Close Lane, Newbury to A34West Berkshire, Hampshire0.89,2830.8%−5.2%0
3A34 to B3048Hampshire8.85,0181.4%−2.2%2128.1
4B3048 to Saxon Way, AndoverHampshire3.95,0111.5%+6.5%7
5A3057/A3093 to Saxon WayHampshire1.112,8801.1%−5.5%1455.9
6A303/A342 roundabout to A3057Hampshire2.214,5570.9%+13.4%1424.8
7B3084 to A303Hampshire5.310,0813.7%−6.7%2021.3
8B3084 Romsey Rd to B3084 Wallop RdHampshire0.310,2841.9%+2.2%0
9B3084 to A30Hampshire, Wiltshire2.87,2613.1%−1.3%6

Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the A343 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.

A343 traffic by vehicle type

Cars and taxis make up 80.4% of the vehicle miles on the A343. HGVs account for 1.9%, rising to 3.7% on B3084 to A303.

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 A343, by year
Year HGV share
2000 4.6%
2001 3.6%
2002 3.5%
2003 3.7%
2004 3.8%
2005 3.5%
2006 3.4%
2007 3.3%
2008 3.4%
2009 3.1%
2010 3.2%
2011 3.2%
2012 3.3%
2013 3.3%
2014 3.2%
2015 3.1%
2016 3.1%
2017 2.5%
2018 2.4%
2019 2.3%
2020 2.6%
2021 2.4%
2022 2.3%
2023 2.1%
2024 2.0%
2025 1.9%

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

A343 traffic trend

Traffic on the A343 came to 81.3 million vehicle miles in 2025. At the count points present in both years, it is down 0.7% on 2019, before the pandemic, and up 6.2% on 2015.

Vehicle miles a year

Like for like, traffic is up 0.6% on 2000.

Vehicle miles on the A343 each year, the whole road as it was that year
Year Vehicle miles
2000 76m
2001 72m
2002 72m
2003 74m
2004 75m
2005 73m
2006 73m
2007 75m
2008 73m
2009 73m
2010 72m
2011 73m
2012 71m
2013 71m
2014 73m
2015 73m
2016 73m
2017 76m
2018 79m
2019 82m
2020 63m
2021 71m
2022 76m
2023 78m
2024 80m
2025 81m

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

Average daily flow

Average daily flow along the A343, weighted by link length, by year
Year Vehicles a day
2000 7,770
2001 7,351
2002 7,419
2003 7,565
2004 7,727
2005 7,505
2006 7,509
2007 7,722
2008 7,451
2009 7,450
2010 7,400
2011 7,459
2012 7,299
2013 7,244
2014 7,437
2015 7,468
2016 7,490
2017 7,754
2018 7,972
2019 8,186
2020 6,247
2021 7,046
2022 7,582
2023 7,817
2024 7,990
2025 8,132

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, 2 of the 11 count points were counted; DfT estimated the rest from earlier counts and local trends.

A343 collisions

Police recorded 98 collisions with the A343 as the first road from 2021 to 2025, fewer than 3 of them fatal or serious. That is 25.4 per 100 million vehicle miles, lower than the 31.5 for all A-roads in Great Britain. On average there were 0.7 a year for each mile of road.

Reported collisions by year

Up 84.6% from 2021 to 2025.

Police-reported collisions on the A343 by year
Year Collisions
2021 13
2022 20
2023 22
2024 19
2025 24

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 A343, 2021 to 2025
Section Per 100m vehicle miles
A3057/A3093 to Saxon Way Hampshire · 14 collisions 55.9
Garden Close Lane to A339 West Berkshire · 16 collisions 32.5
A34 to B3048 Hampshire · 21 collisions 28.1
A303/A342 roundabout to A3057 Hampshire · 14 collisions 24.8
B3084 to A303 Hampshire · 20 collisions 21.3

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

A further 19 collisions were recorded at junctions where the A343 was the second road; they are not in the figures above. Fatal or serious uses DfT’s adjusted serious figures. 100.0% of the collisions could be placed on a section. How we count collisions

Council areas on the A343

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

  • West Berkshire
  • Hampshire
  • Wiltshire

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 11 count points in 2025 15 September 2026
Reported collisions Road safety open data (STATS19) Department for Transport
Derived statistics UK Motoring
2021 to 2025 98 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.