A-road

A5151 traffic and collisions

The A5151 is an A-road of 8.4 miles, from Flintshire to Denbighshire. This page covers its traffic at 5 DfT count points since 2000 and the collisions police recorded on it.

Last updated
Records analysed
5 count points in 2025
Methodology
View methodology
  • Traffic in 2025 18m vehicle miles
  • Average daily traffic 5,854 vehicles a day, both directions
  • Busiest section 7,003 A55 to A5026
  • HGV share 1.9% of vehicle miles
  • Traffic since 2019 −4.1% same count points
  • Collisions, 2021 to 2025 10 4 fatal or serious

How busy is the A5151?

On an average day in 2025, 5,854 vehicles passed each point on the A5151, counting both directions. The busiest section is A55 to A5026 (Flintshire), with 7,003 a day; the quietest listed is Dyserth Rd, Rhuddlan to B5119 Waterfall Road (Ffordd-y-Rhaeadr), with 4,323.

Busiest sections, 2025

A55 to A5026 carries 1.2 times the road’s average flow.

Sections of the A5151 with the highest average daily flow, 2025
Section Vehicles a day
A55 to A5026 Flintshire · 0.8 mi · HGVs 1.9% 7,003
A5026 to B5119 Flintshire, Denbighshire · 5.4 mi · HGVs 2.3% 6,272
Dyserth Rd, Rhuddlan to B5119 Waterfall Road (Ffordd-y-Rhaeadr) Denbighshire · 1.8 mi · HGVs 0.9% 4,323

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

Route

Flintshire to Denbighshire · 8.4 miles

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

A5151 traffic and collisions by section

4 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 A5151 in route order, 2025 traffic
#
1A55 to A5026Flintshire0.87,0031.9%+21.9%fewer than 3
2A5026 to B5119Flintshire, Denbighshire5.46,2722.3%−6.6%6
3Dyserth Rd, Rhuddlan to B5119 Waterfall Road (Ffordd-y-Rhaeadr)Denbighshire1.84,3230.9%−6.9%fewer than 3
4A547 to Dyserth RdDenbighshire0.44,7980.9%−6.9%0

Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the A5151 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.

A5151 traffic by vehicle type

Cars and taxis make up 80.5% of the vehicle miles on the A5151. HGVs account for 1.9%.

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 A5151, by year
Year HGV share
2000 2.4%
2001 2.4%
2002 2.7%
2003 2.5%
2004 2.3%
2005 2.2%
2006 2.2%
2007 2.3%
2008 1.9%
2009 1.7%
2010 1.8%
2011 1.8%
2012 1.9%
2013 1.8%
2014 1.8%
2015 1.8%
2016 1.8%
2017 1.8%
2018 1.9%
2019 1.9%
2020 2.3%
2021 2.2%
2022 2.1%
2023 2.0%
2024 2.0%
2025 1.9%

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

A5151 traffic trend

Traffic on the A5151 came to 17.9 million vehicle miles in 2025. At the count points present in both years, it is down 4.1% on 2019, before the pandemic, and down 2.8% on 2015.

Vehicle miles a year

Like for like, traffic is up 7.4% on 2000.

Vehicle miles on the A5151 each year, the whole road as it was that year
Year Vehicle miles
2000 17m
2001 17m
2002 17m
2003 18m
2004 17m
2005 18m
2006 18m
2007 18m
2008 20m
2009 19m
2010 19m
2011 19m
2012 19m
2013 18m
2014 18m
2015 19m
2016 18m
2017 19m
2018 19m
2019 19m
2020 14m
2021 16m
2022 17m
2023 17m
2024 17m
2025 18m

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

Average daily flow

Average daily flow along the A5151, weighted by link length, by year
Year Vehicles a day
2000 5,452
2001 5,488
2002 5,572
2003 5,899
2004 5,676
2005 5,708
2006 5,883
2007 5,892
2008 6,431
2009 6,135
2010 6,060
2011 6,151
2012 6,098
2013 5,868
2014 5,956
2015 6,024
2016 5,767
2017 6,075
2018 6,090
2019 6,102
2020 4,581
2021 5,046
2022 5,445
2023 5,566
2024 5,637
2025 5,854

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, 1 of the 5 count points were counted; DfT estimated the rest from earlier counts and local trends.

A5151 collisions

Police recorded 10 collisions with the A5151 as the first road from 2021 to 2025, 4 of them fatal or serious.

Reported collisions by year

Police-reported collisions on the A5151 by year
Year Collisions Fatal or serious
2021 3 0
2022 fewer than 3 0
2023 3 fewer than 3
2024 fewer than 3 fewer than 3
2025 0 0

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

A further 3 collisions were recorded at junctions where the A5151 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 A5151

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

  • Flintshire
  • Denbighshire

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 5 count points in 2025 15 September 2026
Reported collisions Road safety open data (STATS19) Department for Transport
Derived statistics UK Motoring
2021 to 2025 10 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.