Trunk A-road
A21 traffic and collisions
The A21 is a trunk A-road of 53.9 miles, from Lewisham to East Sussex. This page covers its traffic at 32 DfT count points since 2000 and the collisions police recorded on it.
- Traffic in 2025 514m vehicle miles
- Average daily traffic 26,143 vehicles a day, both directions
- Busiest section 49,184 B245 R/About to A26
- HGV share 3.8% of vehicle miles
- Traffic since 2019 −5.3% same count points
- Collisions, 2021 to 2025 1,150 45.5 per 100m vehicle miles
How busy is the A21?
On an average day in 2025, 26,143 vehicles passed each point on the A21, counting both directions. The busiest section is B245 R/About to A26 (Kent), with 49,184 a day; the quietest listed is A259 Carlisle Parade/Denmark Place to A2102 London Rd, with 12,089.
Busiest sections, 2025
B245 R/About to A26 carries 1.9 times the road’s average flow.
| Section | Vehicles a day |
|---|---|
| B245 R/About to A26 Kent · 5.1 mi · HGVs 4.4% | 49,184 |
| A225 to A25 Kent · 4.2 mi · HGVs 4.3% | 47,323 |
| A2014 to A228 Kent · 2.9 mi · HGVs 3.0% | 44,648 |
| A26 to A2014 Kent · 0.7 mi · HGVs 4.4% | 31,638 |
| A228 to B2162 Kent · 5.3 mi · HGVs 4.1% | 27,450 |
| A223 to M25 Bromley · 2.3 mi · HGVs 3.9% | 27,429 |
| A2101 St Helens Road to A2100 Junction Road East Sussex · 1.2 mi · HGVs 1.0% | 24,439 |
| A232 to B2158 Farnborough Hill Bromley · 1.7 mi · HGVs 4.7% | 23,255 |
| B2158 Farnborough Hill to A223 Bromley · 0.6 mi · HGVs 4.7% | 21,162 |
| B2162 to B2169 Kent · 1.6 mi · HGVs 4.2% | 20,639 |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Route
Lewisham to East Sussex · 53.9 miles
A21 traffic and collisions by section
29 sections between junctions, in route order. Each is the average of its DfT count points, weighted by length. 1 short link roads and spurs (0.2 miles) count in the road’s totals but are not listed.
Show all 29 sections Tap a column heading to sort
| # | |||
|---|---|---|---|
| 1 | A205 to A20Lewisham | 20,489 | 259 |
| 2 | At A21Lewisham | 22,530 | 15 |
| 3 | A205 to A2218Lewisham | 20,618 | 128 |
| 4 | A2218 to A2015Lewisham | 30,805 | 14 |
| 5 | A2015 to A2212Lewisham, Bromley | 18,969 | 102 |
| 6 | A2212 to A222Bromley | 26,350 | 24 |
| 7 | A222 to A233Bromley | 19,655 | 66 |
| 8 | A233 to A232Bromley | 16,725 | 31 |
| 9 | A232 to B2158 Farnborough HillBromley | 23,255 | 23 |
| 10 | B2158 Farnborough Hill to A223Bromley | 21,162 | 8 |
| 11 | A223 to M25Bromley | 27,429 | 28 |
| 12 | A225 to A25Kent | 47,323 | 45 |
| 13 | B245 R/About to A26Kent | 49,184 | 37 |
| 14 | A26 to A2014Kent | 31,638 | 4 |
| 15 | A2014 Pembury Road to A2014 Vauxhall LaneKent | 40,183 | fewer than 3 |
| 16 | A2014 to A228Kent | 44,648 | 23 |
| 17 | A228 to B2162Kent | 27,450 | 63 |
| 18 | B2162 to B2169Kent | 20,639 | 11 |
| 19 | B2169 to B2079Kent | 16,859 | 30 |
| 20 | B2079 to A268Kent, East Sussex | 19,815 | 6 |
| 21 | B2099 to B2087East Sussex | 14,491 | 23 |
| 22 | A2290 to A265East Sussex | 18,599 | 6 |
| 23 | A265 to A2100East Sussex | 16,437 | 33 |
| 24 | A2100 to B2089East Sussex | 13,318 | 12 |
| 25 | B2089 to B2244East Sussex | 13,471 | 24 |
| 26 | B2244 to A28East Sussex | 18,274 | 43 |
| 27 | A2101 St Helens Road to A2100 Junction RoadEast Sussex | 24,439 | 29 |
| 28 | A2102 London Road to A2101 St Helen's RoadEast Sussex | 12,914 | 24 |
| 29 | A259 Carlisle Parade/Denmark Place to A2102 London RdEast Sussex | 12,089 | 37 |
Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the A21 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.
A21 traffic by vehicle type
Cars and taxis make up 75.2% of the vehicle miles on the A21. HGVs account for 3.8%, rising to 6.2% on A2290 to A265.
Vehicle mix, 2025
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
HGV share of traffic
| Year | HGV share |
|---|---|
| 2000 | 4.9% |
| 2001 | 4.7% |
| 2002 | 4.6% |
| 2003 | 4.5% |
| 2004 | 4.6% |
| 2005 | 4.6% |
| 2006 | 4.4% |
| 2007 | 4.5% |
| 2008 | 4.4% |
| 2009 | 4.2% |
| 2010 | 4.2% |
| 2011 | 4.2% |
| 2012 | 4.3% |
| 2013 | 4.4% |
| 2014 | 4.4% |
| 2015 | 4.3% |
| 2016 | 4.4% |
| 2017 | 4.2% |
| 2018 | 4.0% |
| 2019 | 3.8% |
| 2020 | 4.4% |
| 2021 | 4.1% |
| 2022 | 3.7% |
| 2023 | 3.7% |
| 2024 | 3.7% |
| 2025 | 3.8% |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
A21 traffic trend
Traffic on the A21 came to 514 million vehicle miles in 2025. At the count points present in both years, it is down 5.3% on 2019, before the pandemic, and up 6.1% on 2015.
Vehicle miles a year
Like for like, traffic is up 6.0% on 2000.
| Year | Vehicle miles |
|---|---|
| 2000 | 472m |
| 2001 | 491m |
| 2002 | 495m |
| 2003 | 508m |
| 2004 | 509m |
| 2005 | 509m |
| 2006 | 485m |
| 2007 | 496m |
| 2008 | 479m |
| 2009 | 476m |
| 2010 | 477m |
| 2011 | 481m |
| 2012 | 464m |
| 2013 | 448m |
| 2014 | 462m |
| 2015 | 483m |
| 2016 | 497m |
| 2017 | 507m |
| 2018 | 525m |
| 2019 | 541m |
| 2020 | 421m |
| 2021 | 471m |
| 2022 | 520m |
| 2023 | 513m |
| 2024 | 513m |
| 2025 | 514m |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Average daily flow
| Year | Vehicles a day |
|---|---|
| 2000 | 24,300 |
| 2001 | 25,298 |
| 2002 | 25,483 |
| 2003 | 26,164 |
| 2004 | 26,223 |
| 2005 | 26,220 |
| 2006 | 24,857 |
| 2007 | 25,467 |
| 2008 | 24,595 |
| 2009 | 24,427 |
| 2010 | 24,479 |
| 2011 | 24,678 |
| 2012 | 23,813 |
| 2013 | 23,002 |
| 2014 | 23,723 |
| 2015 | 24,760 |
| 2016 | 25,504 |
| 2017 | 26,005 |
| 2018 | 26,874 |
| 2019 | 27,559 |
| 2020 | 21,452 |
| 2021 | 23,927 |
| 2022 | 26,438 |
| 2023 | 26,049 |
| 2024 | 26,066 |
| 2025 | 26,143 |
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, 11 of the 32 count points were counted; DfT estimated the rest from earlier counts and local trends.
A21 collisions
Police recorded 1,150 collisions with the A21 as the first road from 2021 to 2025, 257 of them fatal or serious. That is 45.5 per 100 million vehicle miles, higher than the 31.5 for all A-roads in Great Britain. On average there were 4.3 a year for each mile of road.
Reported collisions by year
Down 13.3% from 2021 to 2025.
| Year | Slight | Fatal or serious |
|---|---|---|
| 2021 | 189 | 44 |
| 2022 | 203 | 54 |
| 2023 | 183 | 52 |
| 2024 | 172 | 51 |
| 2025 | 146 | 56 |
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 |
|---|---|
| A205 to A20 Lewisham · 259 collisions | 497.3 |
| A205 to A2218 Lewisham · 128 collisions | 269.3 |
| A2015 to A2212 Lewisham, Bromley · 102 collisions | 168.1 |
| A2102 London Road to A2101 St Helen's Road East Sussex · 24 collisions | 150.2 |
| A259 Carlisle Parade/Denmark Place to A2102 London Rd East Sussex · 37 collisions | 114.4 |
| A233 to A232 Bromley · 31 collisions | 101.4 |
| A222 to A233 Bromley · 66 collisions | 84.1 |
| A2100 to B2089 East Sussex · 12 collisions | 56.5 |
Source:DfT STATS19,UK Motoring analysis 2021 to 2025 Updated
A further 133 collisions were recorded at junctions where the A21 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 A21
In route order. Each is the highway authority DfT files the count points under.
- Lewisham
- Bromley
- Kent
- East Sussex
Planned closures on the A21 in England
National Highways has 25 planned closures on the A21 between 16 September 2026 and 30 September 2026, all of them starting in that period. 17 close a carriageway rather than a lane or slip road, and 25 start between 7pm and 6am.
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Carriageway A21 both directions Johns Cross roundabout to Northbridge Street roundabout carriageway closure
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Carriageway A21 both directions Johns Cross roundabout to Northbridge Street roundabout carriageway closure
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Carriageway A21 Southbound Chipstead Westbound exit slip road closure
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Carriageway A21 both directions Johns Cross roundabout to Northbridge Street roundabout carriageway closure
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Carriageway A21 northbound Westerham Road west exit slip road closure
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Carriageway A21 both directions Johns Cross roundabout to Northbridge Street roundabout carriageway closure
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Carriageway A21 both directions Kippings Cross to Forstal Farm carriageway closurea
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Carriageway A21 northbound Westerham Road west exit slip road closure
17 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 | 32 count points in 2025 | 15 September 2026 |
| Reported collisions | Road safety open data (STATS19) Department for Transport Derived statistics UK Motoring | 2021 to 2025 | 1,150 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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