Trunk A-road
A303 traffic and collisions
The A303 is a trunk A-road of 100.1 miles, from Hampshire to Devon. This page covers its traffic at 34 DfT count points since 2000 and the collisions police recorded on it.
- Traffic in 2025 1.1bn vehicle miles
- Average daily traffic 31,298 vehicles a day, both directions
- Busiest section 60,073 A30 to A3093
- HGV share 6.3% of vehicle miles
- Traffic since 2019 +3.8% same count points
- Collisions, 2021 to 2025 553 10.7 per 100m vehicle miles
How busy is the A303?
On an average day in 2025, 31,298 vehicles passed each point on the A303, counting both directions. The busiest section is A30 to A3093 (Hampshire), with 60,073 a day; the quietest listed is A358 to A30, with 17,029.
Busiest sections, 2025
A30 to A3093 carries 1.9 times the road’s average flow.
| Section | Vehicles a day |
|---|---|
| A30 to A3093 Hampshire · 5.5 mi · HGVs 6.6% | 60,073 |
| A3093 to A3057 Hampshire · 1.6 mi · HGVs 5.5% | 59,809 |
| A303 spur to A343 to A342/A343 roundabout Hampshire · 0.8 mi · HGVs 5.4% | 58,029 |
| A3057 to A303 spur to A343 Hampshire · 1.4 mi · HGVs 5.8% | 56,306 |
| A3088 to A356 Somerset · 1.9 mi · HGVs 5.2% | 46,490 |
| A30/M3 to A30 Hampshire · 5.8 mi · HGVs 5.5% | 42,385 |
| A372 to spur to A37 Somerset · 2.5 mi · HGVs 5.7% | 39,682 |
| A338 to A3028 Wiltshire · 2.8 mi · HGVs 7.3% | 39,206 |
| A356 to A358 Somerset · 8.5 mi · HGVs 6.8% | 36,671 |
| A342/A343 roundabout to A338 Hampshire · 7.2 mi · HGVs 6.8% | 36,238 |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Route
Hampshire to Devon · 100.1 miles
A303 traffic and collisions by section
22 sections between junctions, in route order. Each is the average of its DfT count points, weighted by length. 9 short link roads and spurs (2.3 miles) count in the road’s totals but are not listed.
Show all 22 sections Tap a column heading to sort
| # | |||
|---|---|---|---|
| 1 | A30/M3 to A30Hampshire | 42,385 | 29 |
| 2 | At A30Hampshire | 46,106 | fewer than 3 |
| 3 | A30 to A3093Hampshire | 60,073 | 36 |
| 4 | A3093 to A3057Hampshire | 59,809 | 8 |
| 5 | A3057 to A303 spur to A343Hampshire | 56,306 | 16 |
| 6 | A303 spur to A343 to A342/A343 roundaboutHampshire | 58,029 | 8 |
| 7 | A342/A343 roundabout to A338Hampshire | 36,238 | 44 |
| 8 | A338 to A3028Wiltshire | 39,206 | 13 |
| 9 | A3028 to A345Wiltshire | 32,624 | 20 |
| 10 | A344 to A360Wiltshire | 26,270 | 46 |
| 11 | A360 to A303 spurWiltshire | 25,899 | 55 |
| 12 | A303 spur to A350Wiltshire | 21,752 | 59 |
| 13 | A350 to B3081Wiltshire, Dorset, Somerset | 24,946 | 35 |
| 14 | B3081 to A371Somerset | 28,402 | 6 |
| 15 | A371 to A359Somerset | 24,682 | 15 |
| 16 | At A359Somerset | 26,063 | 3 |
| 17 | A37 to B3151Somerset | 25,167 | 14 |
| 18 | A372 to spur to A37Somerset | 39,682 | 11 |
| 19 | spur to A37 to A3088Somerset | 30,522 | 23 |
| 20 | A3088 to A356Somerset | 46,490 | 17 |
| 21 | A356 to A358Somerset | 36,671 | 34 |
| 22 | A358 to A30Somerset, Devon | 17,029 | 51 |
Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the A303 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.
A303 traffic by vehicle type
Cars and taxis make up 77.3% of the vehicle miles on the A303. HGVs account for 6.3%, rising to 7.4% on spur to A37 to A3088.
Vehicle mix, 2025
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
HGV share of traffic
| Year | HGV share |
|---|---|
| 2000 | 8.5% |
| 2001 | 8.1% |
| 2002 | 8.2% |
| 2003 | 7.8% |
| 2004 | 8.1% |
| 2005 | 7.9% |
| 2006 | 7.9% |
| 2007 | 8.0% |
| 2008 | 7.9% |
| 2009 | 7.3% |
| 2010 | 7.3% |
| 2011 | 7.2% |
| 2012 | 7.3% |
| 2013 | 7.4% |
| 2014 | 7.4% |
| 2015 | 7.6% |
| 2016 | 7.6% |
| 2017 | 7.1% |
| 2018 | 7.2% |
| 2019 | 7.3% |
| 2020 | 8.9% |
| 2021 | 8.5% |
| 2022 | 7.4% |
| 2023 | 7.0% |
| 2024 | 6.9% |
| 2025 | 6.3% |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
A303 traffic trend
Traffic on the A303 came to 1.14 billion vehicle miles in 2025. At the count points present in both years, it is up 3.8% on 2019, before the pandemic, and up 27.0% on 2015.
Vehicle miles a year
Like for like, traffic is up 38.4% on 2000.
| Year | Vehicle miles |
|---|---|
| 2000 | 799m |
| 2001 | 855m |
| 2002 | 865m |
| 2003 | 858m |
| 2004 | 852m |
| 2005 | 855m |
| 2006 | 882m |
| 2007 | 878m |
| 2008 | 879m |
| 2009 | 871m |
| 2010 | 852m |
| 2011 | 855m |
| 2012 | 863m |
| 2013 | 862m |
| 2014 | 859m |
| 2015 | 889m |
| 2016 | 930m |
| 2017 | 1.0bn |
| 2018 | 1.0bn |
| 2019 | 1.1bn |
| 2020 | 769m |
| 2021 | 928m |
| 2022 | 1.0bn |
| 2023 | 1.0bn |
| 2024 | 1.0bn |
| 2025 | 1.1bn |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Average daily flow
| Year | Vehicles a day |
|---|---|
| 2000 | 22,538 |
| 2001 | 24,136 |
| 2002 | 24,393 |
| 2003 | 24,201 |
| 2004 | 24,044 |
| 2005 | 24,121 |
| 2006 | 24,898 |
| 2007 | 24,783 |
| 2008 | 24,800 |
| 2009 | 24,563 |
| 2010 | 24,049 |
| 2011 | 24,110 |
| 2012 | 24,350 |
| 2013 | 24,324 |
| 2014 | 24,225 |
| 2015 | 25,083 |
| 2016 | 26,229 |
| 2017 | 28,891 |
| 2018 | 28,957 |
| 2019 | 30,485 |
| 2020 | 21,545 |
| 2021 | 25,993 |
| 2022 | 27,940 |
| 2023 | 29,084 |
| 2024 | 28,877 |
| 2025 | 31,298 |
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 (84.0% of today’s road for 2019). In 2025, 12 of the 34 count points were counted; DfT estimated the rest from earlier counts and local trends.
A303 collisions
Police recorded 553 collisions with the A303 as the first road from 2021 to 2025, 160 of them fatal or serious, including 28 fatal. That is 10.7 per 100 million vehicle miles, lower than the 31.5 for all A-roads in Great Britain. On average there were 1.1 a year for each mile of road.
Reported collisions by year
Up 22.2% from 2021 to 2025.
| Year | Slight | Fatal or serious |
|---|---|---|
| 2021 | 70 | 29 |
| 2022 | 85 | 33 |
| 2023 | 77 | 30 |
| 2024 | 77 | 31 |
| 2025 | 84 | 37 |
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.
| Section | Per 100m vehicle miles |
|---|---|
| A37 to B3151 Somerset · 14 collisions | 34.6 |
| A30 to A3093 Hampshire · 36 collisions | 29.9 |
| A344 to A360 Wiltshire · 46 collisions | 27.1 |
| A360 to A303 spur Wiltshire · 55 collisions | 20.5 |
| A303 spur to A350 Wiltshire · 59 collisions | 20.0 |
| A358 to A30 Somerset, Devon · 51 collisions | 17.8 |
| A3028 to A345 Wiltshire · 20 collisions | 16.3 |
| spur to A37 to A3088 Somerset · 23 collisions | 14.0 |
Source:DfT STATS19,UK Motoring analysis 2021 to 2025 Updated
A further 44 collisions were recorded at junctions where the A303 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 A303
In route order. Each is the highway authority DfT files the count points under.
- Hampshire
- Wiltshire
- Dorset
- Somerset
- Devon
Planned closures on the A303 in England
National Highways has 17 planned closures on the A303 between 16 September 2026 and 30 September 2026, all of them starting in that period. 9 close a carriageway rather than a lane or slip road, and 17 start between 7pm and 6am.
-
Lane or slip A303 eastbound Willoughby Hedge to A350 Jct lane 2 closure
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Lane or slip A303 eastbound Willoughby Hedge to A350 Jct lane 2 closure
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Lane or slip Eastbound lane 2 closure
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Carriageway A303 eastbound Parkhouse Cross to Thruxton Village carriageway closure
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Carriageway A303 both directions A350 Jct to Deptford carriageway closure
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Lane or slip A303 eastbound Willoughby Hedge to A350 Jct lane 2 closure
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Carriageway A303 eastbound Parkhouse Cross to Thruxton Village carriageway closure
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Carriageway A303 both directions A350 Jct to Deptford carriageway closure
9 more planned closures in this period are not shown.
Planned closures only: National Highways can cancel or change them, and closures caused by incidents are not shown. Council roads in England are not covered. Roadworks and closures across the UK
Source:National Highways 2026-09-16 to 2026-09-30 Updated
Data sources and methodology
| 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 | 34 count points in 2025 | 15 September 2026 |
| Reported collisions | Road safety open data (STATS19) Department for Transport Derived statistics UK Motoring | 2021 to 2025 | 553 reported collisions | 15 September 2026 |
| Planned closures | Transport Data Feeds (DATEX II) National Highways | 2026-09-16 to 2026-09-30 | 2,304 planned closure schemes | 16 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.
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