A-road

A666 traffic and collisions

The A666 is an A-road of 25.9 miles, from Salford to Lancashire. This page covers its traffic at 28 DfT count points since 2000 and the collisions police recorded on it.

Last updated
Records analysed
28 count points in 2025
Methodology
View methodology
  • Traffic in 2025 185m vehicle miles
  • Average daily traffic 19,586 vehicles a day, both directions
  • Busiest section 60,889 M61 to A575
  • HGV share 2.3% of vehicle miles
  • Traffic since 2019 +1.6% same count points
  • Collisions, 2021 to 2025 300 35.7 per 100m vehicle miles

How busy is the A666?

On an average day in 2025, 19,586 vehicles passed each point on the A666, counting both directions. The busiest section is M61 to A575 (Bolton), with 60,889 a day; the quietest listed is Longworth Rd to B6193, with 5,876.

Busiest sections, 2025

M61 to A575 carries 3.1 times the road’s average flow.

Sections of the A666 with the highest average daily flow, 2025
Section Vehicles a day
M61 to A575 Bolton · 1.5 mi · HGVs 2.7% 60,889
A575 to A579 Bolton · 1.4 mi · HGVs 2.3% 59,012
Bradford Street to Folds Road Bolton · 0.5 mi · HGVs 2.0% 44,985
A6099 to A58 Bolton · 0.9 mi · HGVs 1.4% 24,021
A58 to B6472 Bolton · 1.7 mi · HGVs 1.6% 19,064
A6062 to A6078 Blackburn with Darwen · 1.0 mi · HGVs 1.0% 18,127
A6044 to M60 Salford · 1.7 mi · HGVs 2.4% 17,755
M60 to A667 Salford, Bolton · 2.1 mi · HGVs 2.4% 14,754
Watery Lane to M65 slip Blackburn with Darwen · 2.6 mi · HGVs 3.3% 14,634
M65 to A6062 intersection Blackburn with Darwen · 1.2 mi · HGVs 2.1% 13,008

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

Route

Salford to Lancashire · 25.9 miles

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

A666 traffic and collisions by section

24 sections between junctions, in route order. Each is the average of its DfT count points, weighted by length. 1 short link roads and spurs (0.3 miles) count in the road’s totals but are not listed.

Show all 24 sections Tap a column heading to sort
Sections of the A666 in route order, 2025 traffic
#
1A6 to A6044Salford0.415,7744.6%−4.8%4
2A6044 to M60Salford1.717,7552.4%−5.5%2445.0
3M60 to A667Salford, Bolton2.114,7542.4%−3.9%1120.2
4A667 to M61Bolton0.228,0802.5%−4.7%8
5M61 to A6053Bolton0.212,1782.7%+6.8%fewer than 3
6M61 to A575Bolton1.560,8892.7%+6.8%5
7A575 to A579Bolton1.459,0122.3%1033.2
8Bradford Street to Folds RoadBolton0.544,9852.0%−6.9%3
9A676 to A673Bolton0.347,5172.0%+9.7%3
10A673 to A6099Bolton0.433,1411.8%+16.2%5
11A6099 to A58Bolton0.924,0211.4%+22.5%2566.2
12A58 to B6472Bolton1.719,0641.6%+5.5%1426.6
13B6472 to Longworth rdBolton0.78,7972.0%−5.7%4
14Longworth Rd to B6193Bolton, Blackburn with Darwen1.85,8763.4%−6.7%1053.9
15B6391 to Lark StBlackburn with Darwen1.88,1692.9%+7.5%3
16Lark St to Watery LaneBlackburn with Darwen0.19,0682.9%+7.5%0
17Watery Lane to M65 slipBlackburn with Darwen2.614,6343.3%−5.7%5277.3
18M65 to A6062 intersectionBlackburn with Darwen1.213,0082.1%+8.3%25101.0
19A6062 to A6078Blackburn with Darwen1.018,1271.0%+21.1%2589.7
20A666 to Canterbury StreetBlackburn with Darwen0.212,8190.7%−29.6%fewer than 3
21A677 to A6119Blackburn with Darwen1.88,7440.8%−13.9%40134.2
22A6119 to B6245Blackburn with Darwen, Lancashire0.910,6981.3%−5.7%1376.4
23B6245 to Hollies RdLancashire0.67,6471.2%−5.9%4
24Hollies Rd, Wilpshire to A59Lancashire1.66,5281.3%−7.5%3

Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the A666 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.

A666 traffic by vehicle type

Cars and taxis make up 82.7% of the vehicle miles on the A666. HGVs account for 2.3%, rising to 3.4% on Longworth Rd to B6193.

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 A666, by year
Year HGV share
2000 4.0%
2001 3.9%
2002 4.0%
2003 3.8%
2004 4.0%
2005 4.0%
2006 4.1%
2007 3.9%
2008 4.2%
2009 3.8%
2010 4.1%
2011 3.7%
2012 3.5%
2013 3.6%
2014 3.6%
2015 3.4%
2016 3.3%
2017 3.3%
2018 2.8%
2019 2.5%
2020 2.9%
2021 2.9%
2022 2.6%
2023 2.4%
2024 2.4%
2025 2.3%

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

A666 traffic trend

Traffic on the A666 came to 185 million vehicle miles in 2025. At the count points present in both years, it is up 1.6% on 2019, before the pandemic, and down 1.3% on 2015.

Vehicle miles a year

Like for like, traffic is down 2.5% on 2000.

Vehicle miles on the A666 each year, the whole road as it was that year
Year Vehicle miles
2000 180m
2001 183m
2002 187m
2003 188m
2004 197m
2005 193m
2006 188m
2007 190m
2008 186m
2009 185m
2010 180m
2011 178m
2012 176m
2013 175m
2014 179m
2015 177m
2016 173m
2017 175m
2018 172m
2019 177m
2020 140m
2021 153m
2022 164m
2023 168m
2024 170m
2025 185m

Source:DfT,UK Motoring analysis 2000 to 2025 Updated

Average daily flow

Average daily flow along the A666, weighted by link length, by year
Year Vehicles a day
2000 18,882
2001 19,182
2002 19,828
2003 19,983
2004 20,867
2005 20,252
2006 20,300
2007 20,545
2008 20,180
2009 20,074
2010 19,451
2011 19,243
2012 19,104
2013 18,999
2014 19,329
2015 19,153
2016 18,767
2017 18,971
2018 18,518
2019 18,895
2020 14,998
2021 16,360
2022 17,556
2023 17,988
2024 18,235
2025 19,586

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, 7 of the 28 count points were counted; DfT estimated the rest from earlier counts and local trends.

A666 collisions

Police recorded 300 collisions with the A666 as the first road from 2021 to 2025, 98 of them fatal or serious, including 6 fatal. That is 35.7 per 100 million vehicle miles, higher than the 31.5 for all A-roads in Great Britain. On average there were 2.3 a year for each mile of road.

Reported collisions by year

Up 5.8% from 2021 to 2025.

Police-reported collisions on the A666 by year: fatal or serious, and slight
Year SlightFatal or serious
2021 3517
2022 4416
2023 3920
2024 4925
2025 3520

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 A666, 2021 to 2025
Section Per 100m vehicle miles
A677 to A6119 Blackburn with Darwen · 40 collisions 134.2
M65 to A6062 intersection Blackburn with Darwen · 25 collisions 101.0
A6062 to A6078 Blackburn with Darwen · 25 collisions 89.7
Watery Lane to M65 slip Blackburn with Darwen · 52 collisions 77.3
A6119 to B6245 Blackburn with Darwen, Lancashire · 13 collisions 76.4
A6099 to A58 Bolton · 25 collisions 66.2
Longworth Rd to B6193 Bolton, Blackburn with Darwen · 10 collisions 53.9
A6044 to M60 Salford · 24 collisions 45.0

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

A further 70 collisions were recorded at junctions where the A666 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 A666

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

  • Salford
  • Bolton
  • Blackburn with Darwen
  • Lancashire

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 28 count points in 2025 15 September 2026
Reported collisions Road safety open data (STATS19) Department for Transport
Derived statistics UK Motoring
2021 to 2025 300 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.