A-road

A484 traffic and collisions

The A484 is an A-road of 57.2 miles, from Swansea to Ceredigion. This page covers its traffic at 17 DfT count points since 2000 and the collisions police recorded on it.

Last updated
Records analysed
17 count points in 2025
Methodology
View methodology
  • Traffic in 2025 145m vehicle miles
  • Average daily traffic 6,933 vehicles a day, both directions
  • Busiest section 24,438 A483 to A4240
  • HGV share 2.6% of vehicle miles
  • Traffic since 2019 −3.3% same count points
  • Collisions, 2021 to 2025 183 26.5 per 100m vehicle miles

How busy is the A484?

On an average day in 2025, 6,933 vehicles passed each point on the A484, counting both directions. The busiest section is A483 to A4240 (Swansea), with 24,438 a day; the quietest listed is B4333 to A486, with 1,795.

Busiest sections, 2025

A483 to A4240 carries 3.5 times the road’s average flow.

Sections of the A484 with the highest average daily flow, 2025
Section Vehicles a day
A483 to A4240 Swansea · 3.9 mi · HGVs 2.4% 24,438
A4138 to A476 Carmarthenshire · 1.2 mi · HGVs 0.9% 20,279
A4240 to A4138 Swansea, Carmarthenshire · 2.8 mi · HGVs 2.1% 12,614
A4242 to A4243 Carmarthenshire · 1.2 mi · HGVs 0.6% 12,551
A476 to Maesyrhaf, Pwll Carmarthenshire · 2.2 mi · HGVs 0.9% 12,550
B4309 to A48 Carmarthenshire · 2.2 mi · HGVs 2.6% 11,666
Maesyrhaf, Pwll to B4308 Monksford St Carmarthenshire · 6.8 mi · HGVs 2.8% 5,358
B4308 Monksford St to B4309 Carmarthenshire · 6.9 mi · HGVs 2.1% 5,147
A485 to B4333 Carmarthenshire · 6.3 mi · HGVs 5.3% 4,237
A475E to A487 Carmarthenshire, Ceredigion · 9.9 mi · HGVs 3.6% 4,226

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

Route

Swansea to Ceredigion · 57.2 miles

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

A484 traffic and collisions by section

15 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 A484 in route order, 2025 traffic
#
1A483 to A4240Swansea3.924,4382.4%+5.2%127.4
2A4240 to A4138Swansea, Carmarthenshire2.812,6142.1%−8.0%2743.6
3A4138 to A476Carmarthenshire1.220,2790.9%−14.1%6
4A476 to A4124Carmarthenshire0.215,8771.6%−13.7%5
5A476 to Maesyrhaf, PwllCarmarthenshire2.212,5500.9%−4.2%2755.8
6Maesyrhaf, Pwll to B4308 Monksford StCarmarthenshire6.85,3582.8%−6.3%2031.3
7B4308 Monksford St to B4309Carmarthenshire6.95,1472.1%−7.6%2234.9
8B4309 to A48Carmarthenshire2.211,6662.6%+3.4%7
9A40 to A4242Carmarthenshire0.216,2710.6%+4.2%fewer than 3
10A4242 to A4243Carmarthenshire1.212,5510.6%−5.5%7
11A485 to B4333Carmarthenshire6.34,2375.3%13133.4
12B4333 to A486Carmarthenshire6.91,7955.0%−5.4%6
13A486 to A475WCarmarthenshire6.22,1003.9%−4.5%6
14A475W to A475ECarmarthenshire0.33,2044.7%−7.5%fewer than 3
15A475E to A487Carmarthenshire, Ceredigion9.94,2263.6%−4.6%1419.1

Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the A484 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.

A484 traffic by vehicle type

Cars and taxis make up 80.0% of the vehicle miles on the A484. HGVs account for 2.6%, rising to 5.3% on A485 to B4333.

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 A484, by year
Year HGV share
2000 3.7%
2001 3.3%
2002 3.1%
2003 3.1%
2004 3.1%
2005 3.2%
2006 3.2%
2007 3.1%
2008 3.4%
2009 3.3%
2010 3.3%
2011 3.2%
2012 3.2%
2013 2.8%
2014 2.6%
2015 2.6%
2016 2.6%
2017 2.6%
2018 2.6%
2019 2.6%
2020 3.1%
2021 2.9%
2022 2.8%
2023 2.7%
2024 2.6%
2025 2.6%

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

A484 traffic trend

Traffic on the A484 came to 145 million vehicle miles in 2025. At the count points present in both years, it is down 3.3% on 2019, before the pandemic, and up 1.0% on 2015.

Vehicle miles a year

Like for like, traffic is up 12.6% on 2000.

Vehicle miles on the A484 each year, the whole road as it was that year
Year Vehicle miles
2000 125m
2001 124m
2002 129m
2003 136m
2004 132m
2005 134m
2006 158m
2007 159m
2008 141m
2009 140m
2010 138m
2011 138m
2012 137m
2013 137m
2014 138m
2015 141m
2016 146m
2017 148m
2018 149m
2019 150m
2020 114m
2021 127m
2022 137m
2023 141m
2024 142m
2025 145m

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

Average daily flow

Average daily flow along the A484, weighted by link length, by year
Year Vehicles a day
2000 6,098
2001 6,064
2002 6,314
2003 6,650
2004 6,450
2005 6,558
2006 7,706
2007 7,780
2008 6,907
2009 6,849
2010 6,755
2011 6,759
2012 6,682
2013 6,689
2014 6,751
2015 6,907
2016 7,147
2017 7,231
2018 7,222
2019 7,168
2020 5,431
2021 6,052
2022 6,524
2023 6,700
2024 6,780
2025 6,933

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 (89.0% of today’s road for 2019). In 2025, 3 of the 17 count points were counted; DfT estimated the rest from earlier counts and local trends.

A484 collisions

Police recorded 183 collisions with the A484 as the first road from 2021 to 2025, 63 of them fatal or serious. That is 26.5 per 100 million vehicle miles, lower than the 31.5 for all A-roads in Great Britain. On average there were 0.6 a year for each mile of road.

Reported collisions by year

Down 10.9% from 2021 to 2025.

Police-reported collisions on the A484 by year: fatal or serious, and slight
Year SlightFatal or serious
2021 3115
2022 2310
2023 2213
2024 208
2025 2417

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 A484, 2021 to 2025
Section Per 100m vehicle miles
A485 to B4333 Carmarthenshire · 13 collisions 133.4
A476 to Maesyrhaf, Pwll Carmarthenshire · 27 collisions 55.8
A4240 to A4138 Swansea, Carmarthenshire · 27 collisions 43.6
B4308 Monksford St to B4309 Carmarthenshire · 22 collisions 34.9
Maesyrhaf, Pwll to B4308 Monksford St Carmarthenshire · 20 collisions 31.3
A475E to A487 Carmarthenshire, Ceredigion · 14 collisions 19.1
A483 to A4240 Swansea · 12 collisions 7.4

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

A further 20 collisions were recorded at junctions where the A484 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 A484

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

  • Swansea
  • Carmarthenshire
  • Ceredigion

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 17 count points in 2025 15 September 2026
Reported collisions Road safety open data (STATS19) Department for Transport
Derived statistics UK Motoring
2021 to 2025 183 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.