Trunk A-road

A48 traffic and collisions

The A48 is a trunk A-road of 123.5 miles in England and Wales, from Gloucestershire to Carmarthenshire. This page covers its traffic at 51 DfT count points since 2000 and the collisions police recorded on it.

Last updated
Records analysed
51 count points in 2025
Methodology
View methodology
  • Traffic in 2025 836m vehicle miles
  • Average daily traffic 18,553 vehicles a day, both directions
  • Busiest section 81,977 A4232 to A4161
  • HGV share 3.7% of vehicle miles
  • Traffic since 2019 +3.7% same count points
  • Collisions, 2021 to 2025 569 14.9 per 100m vehicle miles

How busy is the A48?

On an average day in 2025, 18,553 vehicles passed each point on the A48, counting both directions. The busiest section is A4232 to A4161 (Cardiff), with 81,977 a day; the quietest listed is Highfield Rd to roundabout just north of Mead Lane, by Lydney, with 4,710.

Busiest sections, 2025

A4232 to A4161 carries 4.4 times the road’s average flow.

Sections of the A48 with the highest average daily flow, 2025
Section Vehicles a day
A4232 to A4161 Cardiff · 1.7 mi · HGVs 4.0% 81,977
A48M jn29a to A4232 Cardiff · 1.2 mi · HGVs 3.8% 75,787
A469 / A470 to A4119 Cardiff · 1.6 mi · HGVs 0.9% 51,480
A4161 to A469 / A470 Cardiff · 3.2 mi · HGVs 1.6% 48,542
M4 j49 to A476 Carmarthenshire · 3.9 mi · HGVs 5.5% 41,489
A4810 to A4042 Newport · 0.6 mi · HGVs 5.5% 39,758
B4310 to A484 Carmarthenshire · 6.1 mi · HGVs 5.1% 37,964
M4jn28 / A467 to A4042 Maes Glas Newport · 0.7 mi · HGVs 6.7% 33,302
A476 to B4310 Carmarthenshire · 5.5 mi · HGVs 6.3% 32,130
A474 to M4 western spur Neath Port Talbot · 0.8 mi · HGVs 2.3% 31,385

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

Route

Gloucestershire to Carmarthenshire · 123.5 miles

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

A48 traffic and collisions by section

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

Show all 46 sections Tap a column heading to sort
Sections of the A48 in route order, 2025 traffic
#
1A40 to A4151Gloucestershire7.712,9603.2%+7.1%3721.6
2A4151 to Highfield RoadGloucestershire7.66,3913.7%−5.9%1922.3
3Highfield Rd to roundabout just north of Mead Lane, by LydneyGloucestershire2.94,7105.0%4
4Roundabout just north of Mead Lane, by Lydney to EnglandGloucestershire7.610,7015.0%+13.5%3225.0
5England to A466Monmouthshire1.119,5663.3%−5.3%2052.5
6A466 to M4 jn24Monmouthshire, Newport11.76,6752.6%+6.6%3023.0
7M4 Junction 24 to A455Newport1.918,7667.0%+13.9%5
8A455 to A4810Newport1.526,8654.4%+10.1%1013.3
9A4810 to A4042Newport0.639,7585.5%+24.3%2766.9
10A48 to A4042 spurNewport2.529,0226.2%1245.3
11M4jn28 / A467 to A4042 Maes GlasNewport0.733,3026.7%+6.5%8
12Celtic Way to A48MNewport, Cardiff5.116,3881.6%2344.9
13A48M jn29a to A4232Cardiff1.275,7873.8%6
14A4232 to A4161Cardiff1.781,9774.0%−10.6%2410.1
15A4161 to A469 / A470Cardiff3.248,5421.6%1831.8
16A469 / A470 to A4119Cardiff1.651,4800.9%2066.5
17A4119 to A4161Cardiff0.919,7071.1%−5.3%1547.9
18A4161 to A4232 / A4050Cardiff2.519,4770.9%26146.3
19A4232 / A4050 to A4226The Vale of Glamorgan2.916,5844.0%1796.8
20A4226 to A4222 Primrose HillThe Vale of Glamorgan4.313,7754.3%−8.2%1312.4
21A4222 Primrose Hill to A4222 Gibbet's HillThe Vale of Glamorgan1.69,1263.4%+23.7%fewer than 3
22A4222 Gibbet's Hill to A473 HeronstonThe Vale of Glamorgan, Bridgend5.411,7163.0%8
23A473 to B4622Bridgend1.822,4032.5%−4.2%5
24B4622 to A473 LalestonBridgend1.516,2712.9%+2.5%3
25A473 Laleston to A4106Bridgend0.726,1702.2%−5.8%4
26A4106 to A4229Bridgend2.812,2664.7%−6.1%4
27A4229 to M4 jn38Bridgend, Neath Port Talbot4.06,9991.5%−3.1%5
28M4 Junction 38 to A4241Neath Port Talbot0.415,8605.4%−2.9%5
29A4241 to M4 Junction 39Neath Port Talbot0.47,8543.0%−6.0%fewer than 3
30A4107 to M4 J39Neath Port Talbot1.87,7080.4%−12.3%7
31M4 J39 to A4241Neath Port Talbot0.812,6920.6%+20.0%3
32A4241 to M4 J41Neath Port Talbot0.322,0391.9%+5.3%fewer than 3
33M4 J41 to B4286Neath Port Talbot1.77,5430.6%−4.4%7
34B4286 to A474Neath Port Talbot1.230,6241.7%+8.2%fewer than 3
35A474 to M4 western spurNeath Port Talbot0.831,3852.3%+2.4%5
36M4 jn44 to A4217Swansea1.219,1023.1%−15.4%fewer than 3
37A4217 to A4067Swansea0.99,9432.4%−5.2%3
38A4067 to M4 jn46Swansea2.27,7761.5%−4.8%1239.9
39M4 jn46 to M4 jn47Swansea2.17,2041.6%−7.3%3
40M4jn47 to A4240Swansea0.522,5711.8%−6.9%fewer than 3
41A4240 to A48 mergeSwansea3.67,0711.3%5
42A48 merge to A4138Swansea0.47,3021.2%−11.2%fewer than 3
43A4138 to M4 j49Carmarthenshire2.75,7141.3%−6.5%9
44M4 j49 to A476Carmarthenshire3.941,4895.5%+17.1%3011.5
45A476 to B4310Carmarthenshire5.532,1306.3%−1.9%4013.0
46B4310 to A484Carmarthenshire6.137,9645.1%+21.7%277.0

Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the A48 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.

A48 traffic by vehicle type

Cars and taxis make up 79.5% of the vehicle miles on the A48. HGVs account for 3.7%, rising to 7.0% on M4 Junction 24 to A455.

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 A48, by year
Year HGV share
2000 4.9%
2001 4.6%
2002 4.7%
2003 4.4%
2004 4.3%
2005 4.7%
2006 5.0%
2007 4.8%
2008 4.6%
2009 4.2%
2010 4.3%
2011 4.3%
2012 4.2%
2013 4.1%
2014 4.0%
2015 3.9%
2016 3.6%
2017 3.9%
2018 3.8%
2019 3.9%
2020 4.6%
2021 4.3%
2022 4.0%
2023 3.8%
2024 3.8%
2025 3.7%

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

A48 traffic trend

Traffic on the A48 came to 836 million vehicle miles in 2025. At the count points present in both years, it is up 3.7% on 2019, before the pandemic, and up 8.8% on 2015.

Vehicle miles a year

Like for like, traffic is up 19.2% on 2000.

Vehicle miles on the A48 each year, the whole road as it was that year
Year Vehicle miles
2000 723m
2001 710m
2002 756m
2003 750m
2004 779m
2005 777m
2006 782m
2007 799m
2008 792m
2009 778m
2010 763m
2011 762m
2012 746m
2013 745m
2014 773m
2015 800m
2016 784m
2017 784m
2018 803m
2019 790m
2020 592m
2021 670m
2022 742m
2023 776m
2024 801m
2025 836m

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

Average daily flow

Average daily flow along the A48, weighted by link length, by year
Year Vehicles a day
2000 16,281
2001 15,992
2002 16,736
2003 16,598
2004 17,245
2005 17,364
2006 17,474
2007 17,859
2008 17,696
2009 17,379
2010 17,052
2011 17,032
2012 16,660
2013 16,654
2014 17,320
2015 17,928
2016 17,912
2017 17,909
2018 17,914
2019 17,701
2020 13,257
2021 14,982
2022 16,592
2023 17,346
2024 17,923
2025 18,553

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 (76.0% of today’s road for 2019). In 2025, 4 of the 51 count points were counted; DfT estimated the rest from earlier counts and local trends.

A48 collisions

Police recorded 569 collisions with the A48 as the first road from 2021 to 2025, 178 of them fatal or serious. That is 14.9 per 100 million vehicle miles, lower than the 31.5 for all A-roads in Great Britain. On average there were 0.9 a year for each mile of road.

Reported collisions by year

About the same in 2025 as in 2021.

Police-reported collisions on the A48 by year: fatal or serious, and slight
Year SlightFatal or serious
2021 9633
2022 6829
2023 6839
2024 7731
2025 8345

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 A48, 2021 to 2025
Section Per 100m vehicle miles
A4161 to A4232 / A4050 Cardiff · 26 collisions 146.3
A4232 / A4050 to A4226 The Vale of Glamorgan · 17 collisions 96.8
A4810 to A4042 Newport · 27 collisions 66.9
A469 / A470 to A4119 Cardiff · 20 collisions 66.5
England to A466 Monmouthshire · 20 collisions 52.5
A4119 to A4161 Cardiff · 15 collisions 47.9
A48 to A4042 spur Newport · 12 collisions 45.3
Celtic Way to A48M Newport, Cardiff · 23 collisions 44.9

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

A further 94 collisions were recorded at junctions where the A48 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 A48

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

  • Gloucestershire
  • Monmouthshire
  • Newport
  • Cardiff
  • The Vale of Glamorgan
  • Bridgend
  • Neath Port Talbot
  • Swansea
  • Carmarthenshire

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 51 count points in 2025 15 September 2026
Reported collisions Road safety open data (STATS19) Department for Transport
Derived statistics UK Motoring
2021 to 2025 569 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.