Motorway
M621 traffic and collisions
The M621 is a motorway of 10.8 miles, from Kirklees to Leeds. This page covers its traffic at 15 DfT count points since 2000 and the collisions police recorded on it.
- Traffic in 2025 225m vehicle miles
- Average daily traffic 57,171 vehicles a day, both directions
- Busiest section 106,320 J5 to J6
- HGV share 6.0% of vehicle miles
- Traffic since 2019 −6.3% same count points
- Collisions, 2021 to 2025 116 10.5 per 100m vehicle miles
How busy is the M621?
On an average day in 2025, 57,171 vehicles passed each point on the M621, counting both directions. The busiest section is J5 to J6 (Leeds), with 106,320 a day; the quietest listed is SPUR to A62, with 28,948.
Busiest sections, 2025
J5 to J6 carries 1.9 times the road’s average flow.
| Section | Vehicles a day |
|---|---|
| J5 to J6 Leeds · 0.6 mi · HGVs 4.2% | 106,320 |
| J1 to J2 Leeds · 0.7 mi · HGVs 4.5% | 88,055 |
| J2A to J2 Leeds · 1.0 mi · HGVs 7.0% | 80,107 |
| J44 to J43 Leeds · 0.6 mi · HGVs 4.6% | 79,639 |
| M1 to J7 Leeds · 1.2 mi · HGVs 7.4% | 65,435 |
| RD SPLIT to J1 Leeds · 2.5 mi · HGVs 5.9% | 54,877 |
| On M621 (Near Holbeck Moor Road) to Dewsbury Road / M621 Leeds · 0.6 mi · HGVs 6.0% | 54,267 |
| SPUR to A62 Leeds · 0.8 mi · HGVs 5.7% | 28,948 |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Route
Kirklees to Leeds · 10.8 miles
M621 traffic and collisions by section
11 sections between junctions, in route order. Each is the average of its DfT count points, weighted by length. 4 short link roads and spurs (1.8 miles) count in the road’s totals but are not listed.
Sections Tap a column heading to sort
| # | |||
|---|---|---|---|
| 1 | M62 to A62 SPURKirklees | 20,187 | fewer than 3 |
| 2 | SPUR to A62Leeds | 28,948 | fewer than 3 |
| 3 | RD SPLIT to J1Leeds | 54,877 | 16 |
| 4 | J1 to J2Leeds | 88,055 | 16 |
| 5 | J2A to J2Leeds | 80,107 | 26 |
| 6 | On M621 (Near Holbeck Moor Road) to Dewsbury Road / M621Leeds | 54,267 | 3 |
| 7 | J3 to J4Leeds | 77,460 | 6 |
| 8 | J4 to J5Leeds | 85,541 | 15 |
| 9 | J5 to J6Leeds | 106,320 | 7 |
| 10 | J44 to J43Leeds | 79,639 | 5 |
| 11 | M1 to J7Leeds | 65,435 | 6 |
Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the M621 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.
M621 traffic by vehicle type
Cars and taxis make up 76.7% of the vehicle miles on the M621. HGVs account for 6.0%, rising to 7.4% on M1 to J7.
Vehicle mix, 2025
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
HGV share of traffic
| Year | HGV share |
|---|---|
| 2000 | 7.1% |
| 2001 | 6.9% |
| 2002 | 6.8% |
| 2003 | 6.6% |
| 2004 | 6.6% |
| 2005 | 6.4% |
| 2006 | 6.5% |
| 2007 | 6.5% |
| 2008 | 6.5% |
| 2009 | 5.8% |
| 2010 | 5.4% |
| 2011 | 5.3% |
| 2012 | 5.4% |
| 2013 | 5.9% |
| 2014 | 5.8% |
| 2015 | 6.1% |
| 2016 | 6.0% |
| 2017 | 5.6% |
| 2018 | 5.8% |
| 2019 | 6.2% |
| 2020 | 7.8% |
| 2021 | 7.3% |
| 2022 | 6.3% |
| 2023 | 6.5% |
| 2024 | 6.3% |
| 2025 | 6.0% |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
M621 traffic trend
Traffic on the M621 came to 225 million vehicle miles in 2025. At the count points present in both years, it is down 6.3% on 2019, before the pandemic, and up 8.1% on 2015.
Vehicle miles a year
Like for like, traffic is up 16.6% on 2000.
| Year | Vehicle miles |
|---|---|
| 2000 | 174m |
| 2001 | 178m |
| 2002 | 187m |
| 2003 | 185m |
| 2004 | 194m |
| 2005 | 195m |
| 2006 | 195m |
| 2007 | 196m |
| 2008 | 201m |
| 2009 | 203m |
| 2010 | 199m |
| 2011 | 202m |
| 2012 | 202m |
| 2013 | 195m |
| 2014 | 200m |
| 2015 | 211m |
| 2016 | 219m |
| 2017 | 249m |
| 2018 | 247m |
| 2019 | 246m |
| 2020 | 179m |
| 2021 | 211m |
| 2022 | 233m |
| 2023 | 224m |
| 2024 | 213m |
| 2025 | 225m |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Average daily flow
| Year | Vehicles a day |
|---|---|
| 2000 | 45,953 |
| 2001 | 46,866 |
| 2002 | 49,193 |
| 2003 | 48,851 |
| 2004 | 51,094 |
| 2005 | 51,281 |
| 2006 | 51,383 |
| 2007 | 51,689 |
| 2008 | 52,913 |
| 2009 | 53,375 |
| 2010 | 52,498 |
| 2011 | 53,243 |
| 2012 | 53,083 |
| 2013 | 51,305 |
| 2014 | 52,680 |
| 2015 | 55,443 |
| 2016 | 57,779 |
| 2017 | 63,107 |
| 2018 | 62,582 |
| 2019 | 62,287 |
| 2020 | 45,505 |
| 2021 | 53,394 |
| 2022 | 58,636 |
| 2023 | 56,357 |
| 2024 | 53,962 |
| 2025 | 57,171 |
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 (81.5% of today’s road for 2019). In 2025, 8 of the 15 count points were counted; DfT estimated the rest from earlier counts and local trends.
M621 collisions
Police recorded 116 collisions with the M621 as the first road from 2021 to 2025, fewer than 3 of them fatal or serious. That is 10.5 per 100 million vehicle miles, higher than the 4.9 for all motorways in Great Britain. On average there were 2.2 a year for each mile of road.
Reported collisions by year
Up 20.8% from 2021 to 2025.
| Year | Collisions |
|---|---|
| 2021 | 24 |
| 2022 | 31 |
| 2023 | 19 |
| 2024 | 13 |
| 2025 | 29 |
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 |
|---|---|
| J2A to J2 Leeds · 26 collisions | 44.9 |
| J1 to J2 Leeds · 16 collisions | 17.5 |
| RD SPLIT to J1 Leeds · 16 collisions | 6.2 |
Source:DfT STATS19,UK Motoring analysis 2021 to 2025 Updated
A further 27 collisions were recorded at junctions where the M621 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 M621
In route order. Each is the highway authority DfT files the count points under.
- Kirklees
- Leeds
Planned closures on the M621 in England
National Highways has 17 planned closures on the M621 between 16 September 2026 and 30 September 2026, all of them starting in that period. 14 close a carriageway rather than a lane or slip road, and 17 start between 7pm and 6am.
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Carriageway M621 clockwise Jct 27 exit slip road closure
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Carriageway M621 clockwise Jct 2 exit slip road closure
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Carriageway M621 clockwise Jct 2 entry slip road closure
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Carriageway M621 clockwise Jct 3 exit slip road closure
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Carriageway M621 anticlockwise Jct 1 exit slip road closure
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Carriageway M621 anticlockwise Jct 2 entry slip road closure
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Carriageway M621 anticlockwise Jct 3 exit slip road closure
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Carriageway M621 clockwise Jct 7 exit slip road closure
9 more planned closures in this period are not shown.
Planned closures only: National Highways can cancel or change them, and closures caused by incidents are not shown. Council roads in England are not covered. Roadworks and closures across the UK
Source:National Highways 2026-09-16 to 2026-09-30 Updated
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 | 15 count points in 2025 | 15 September 2026 |
| Reported collisions | Road safety open data (STATS19) Department for Transport Derived statistics UK Motoring | 2021 to 2025 | 116 reported collisions | 15 September 2026 |
| Planned closures | Transport Data Feeds (DATEX II) National Highways | 2026-09-16 to 2026-09-30 | 2,304 planned closure schemes | 16 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.
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