A-road
A4054 traffic and collisions
The A4054 is an A-road of 26.2 miles, from Cardiff to Merthyr Tydfil. This page covers its traffic at 24 DfT count points since 2000 and the collisions police recorded on it.
- Traffic in 2025 60m vehicle miles
- Average daily traffic 6,299 vehicles a day, both directions
- Busiest section 11,668 A4060 to A4102
- HGV share 1.2% of vehicle miles
- Traffic since 2019 −5.5% same count points
- Collisions, 2021 to 2025 68 23.8 per 100m vehicle miles
How busy is the A4054?
On an average day in 2025, 6,299 vehicles passed each point on the A4054, counting both directions. The busiest section is A4060 to A4102 (Merthyr Tydfil), with 11,668 a day; the quietest listed is A465 to A470, with 848.
Busiest sections, 2025
A4060 to A4102 carries 1.9 times the road’s average flow.
| Section | Vehicles a day |
|---|---|
| A4060 to A4102 Merthyr Tydfil · 1.3 mi · HGVs 1.2% | 11,668 |
| B4285 Bridge St, Troedyrhiw to A4060 Merthyr Tydfil · 1.2 mi · HGVs 1.0% | 10,787 |
| A470 roundabout to A4054 Common Rd Rhondda Cynon Taf · 1.1 mi · HGVs 0.5% | 7,627 |
| A4102 W to A465 Merthyr Tydfil · 1.4 mi · HGVs 0.9% | 7,415 |
| A472 to Commercial Terrace, Treharris Merthyr Tydfil · 1.1 mi · HGVs 1.3% | 7,257 |
| A4054 Common Rd to Jones St, Gilfynydd Rhondda Cynon Taf · 1.5 mi · HGVs 1.0% | 7,149 |
| A470 roundabout Upper Boat to A470 roundabout Glyntaff Rhondda Cynon Taf · 2.2 mi · HGVs 1.1% | 7,041 |
| A4119 to Pantmawr Rd Cardiff · 1.9 mi · HGVs 0.6% | 6,797 |
| Pantmawr Rd to M4 Cardiff · 0.8 mi · HGVs 0.6% | 6,525 |
| A470 to A465 Cardiff, Rhondda Cynon Taf · 1.9 mi · HGVs 0.8% | 6,091 |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Route
Cardiff to Merthyr Tydfil · 26.2 miles
A4054 traffic and collisions by section
19 sections between junctions, in route order. Each is the average of its DfT count points, weighted by length. 3 short link roads and spurs (0.7 miles) count in the road’s totals but are not listed.
Show all 19 sections Tap a column heading to sort
| # | |||
|---|---|---|---|
| 1 | A4119 to Pantmawr RdCardiff | 6,797 | 7 |
| 2 | Pantmawr Rd to M4Cardiff | 6,525 | 3 |
| 3 | M4/A470 roundabout to B4262 roundaboutCardiff | 2,913 | 0 |
| 4 | A470 to A465Cardiff, Rhondda Cynon Taf | 6,091 | 6 |
| 5 | Cardiff Road roundabout to A470Rhondda Cynon Taf | 5,690 | 11 |
| 6 | A470 roundabout Upper Boat to A470 roundabout GlyntaffRhondda Cynon Taf | 7,041 | 6 |
| 7 | A470 roundabout to A4054 Common RdRhondda Cynon Taf | 7,627 | fewer than 3 |
| 8 | A4054 Common Rd to Jones St, GilfynyddRhondda Cynon Taf | 7,149 | fewer than 3 |
| 9 | Jones St, Gilfynydd to A4054 spur to A470SRhondda Cynon Taf | 4,078 | fewer than 3 |
| 10 | A4054 spur to A470S to A472Rhondda Cynon Taf, Merthyr Tydfil | 5,522 | 3 |
| 11 | A472 to Commercial Terrace, TreharrisMerthyr Tydfil | 7,257 | fewer than 3 |
| 12 | Commercial Terrace, Treharris to B4285 Bridge St, TroedyrhiwMerthyr Tydfil | 3,779 | 3 |
| 13 | B4285 Bridge St, Troedyrhiw to A4060Merthyr Tydfil | 10,787 | fewer than 3 |
| 14 | A4060 to A4102Merthyr Tydfil | 11,668 | 0 |
| 15 | A4102 (S) to AVENUE DE CLICHYMerthyr Tydfil | 16,254 | fewer than 3 |
| 16 | AVENUE DE CLICHYMerthyr Tydfil | 7,018 | 6 |
| 17 | A4102 (N)Merthyr Tydfil | 5,774 | fewer than 3 |
| 18 | A4102 W to A465Merthyr Tydfil | 7,415 | 8 |
| 19 | A465 to A470Merthyr Tydfil | 848 | 0 |
Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the A4054 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.
A4054 traffic by vehicle type
Cars and taxis make up 79.9% of the vehicle miles on the A4054. HGVs account for 1.2%, rising to 3.7% on Jones St, Gilfynydd to A4054 spur to A470S.
Vehicle mix, 2025
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
HGV share of traffic
| Year | HGV share |
|---|---|
| 2000 | 2.9% |
| 2001 | 2.5% |
| 2002 | 2.2% |
| 2003 | 2.3% |
| 2004 | 2.4% |
| 2005 | 2.2% |
| 2006 | 2.1% |
| 2007 | 2.0% |
| 2008 | 1.9% |
| 2009 | 1.7% |
| 2010 | 1.6% |
| 2011 | 1.4% |
| 2012 | 1.5% |
| 2013 | 1.5% |
| 2014 | 1.5% |
| 2015 | 1.3% |
| 2016 | 1.3% |
| 2017 | 1.2% |
| 2018 | 1.2% |
| 2019 | 1.2% |
| 2020 | 1.4% |
| 2021 | 1.3% |
| 2022 | 1.3% |
| 2023 | 1.3% |
| 2024 | 1.2% |
| 2025 | 1.2% |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
A4054 traffic trend
Traffic on the A4054 came to 60.2 million vehicle miles in 2025. At the count points present in both years, it is down 5.5% on 2019, before the pandemic, and down 4.0% on 2015.
Vehicle miles a year
Like for like, traffic is about the same as in 2000.
| Year | Vehicle miles |
|---|---|
| 2000 | 60m |
| 2001 | 58m |
| 2002 | 60m |
| 2003 | 60m |
| 2004 | 60m |
| 2005 | 61m |
| 2006 | 61m |
| 2007 | 61m |
| 2008 | 60m |
| 2009 | 60m |
| 2010 | 62m |
| 2011 | 62m |
| 2012 | 61m |
| 2013 | 61m |
| 2014 | 62m |
| 2015 | 60m |
| 2016 | 61m |
| 2017 | 62m |
| 2018 | 63m |
| 2019 | 63m |
| 2020 | 48m |
| 2021 | 53m |
| 2022 | 57m |
| 2023 | 58m |
| 2024 | 59m |
| 2025 | 60m |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Average daily flow
| Year | Vehicles a day |
|---|---|
| 2000 | 6,489 |
| 2001 | 6,292 |
| 2002 | 6,470 |
| 2003 | 6,481 |
| 2004 | 6,559 |
| 2005 | 6,662 |
| 2006 | 6,598 |
| 2007 | 6,648 |
| 2008 | 6,496 |
| 2009 | 6,567 |
| 2010 | 6,749 |
| 2011 | 6,753 |
| 2012 | 6,659 |
| 2013 | 6,588 |
| 2014 | 6,690 |
| 2015 | 6,563 |
| 2016 | 6,612 |
| 2017 | 6,763 |
| 2018 | 6,745 |
| 2019 | 6,733 |
| 2020 | 5,164 |
| 2021 | 5,678 |
| 2022 | 6,090 |
| 2023 | 6,203 |
| 2024 | 6,295 |
| 2025 | 6,299 |
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 24 count points were counted; DfT estimated the rest from earlier counts and local trends.
A4054 collisions
Police recorded 68 collisions with the A4054 as the first road from 2021 to 2025, 15 of them fatal or serious. That is 23.8 per 100 million vehicle miles, lower than the 31.5 for all A-roads in Great Britain. On average there were 0.5 a year for each mile of road.
Reported collisions by year
Down 33.3% from 2021 to 2025.
| Year | Collisions |
|---|---|
| 2021 | 12 |
| 2022 | 18 |
| 2023 | 14 |
| 2024 | 16 |
| 2025 | 8 |
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 |
|---|---|
| Cardiff Road roundabout to A470 Rhondda Cynon Taf · 11 collisions | 72.9 |
Source:DfT STATS19,UK Motoring analysis 2021 to 2025 Updated
A further 26 collisions were recorded at junctions where the A4054 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 A4054
In route order. Each is the highway authority DfT files the count points under.
- Cardiff
- Rhondda Cynon Taf
- Merthyr Tydfil
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 | 24 count points in 2025 | 15 September 2026 |
| Reported collisions | Road safety open data (STATS19) Department for Transport Derived statistics UK Motoring | 2021 to 2025 | 68 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.