A-road
A418 traffic and collisions
The A418 is an A-road of 23.8 miles, from Central Bedfordshire to Oxfordshire. This page covers its traffic at 12 DfT count points since 2000 and the collisions police recorded on it.
- Traffic in 2025 161m vehicle miles
- Average daily traffic 18,515 vehicles a day, both directions
- Busiest section 25,508 Coldharbour Way, Aylesbury to A4129
- HGV share 4.1% of vehicle miles
- Traffic since 2019 −2.2% same count points
- Collisions, 2021 to 2025 126 17.3 per 100m vehicle miles
How busy is the A418?
On an average day in 2025, 18,515 vehicles passed each point on the A418, counting both directions. The busiest section is Coldharbour Way, Aylesbury to A4129 (Buckinghamshire, Oxfordshire), with 25,508 a day; the quietest listed is A329 to A40, with 11,601.
Busiest sections, 2025
Coldharbour Way, Aylesbury to A4129 carries 1.4 times the road’s average flow.
| Section | Vehicles a day |
|---|---|
| Coldharbour Way, Aylesbury to A4129 Buckinghamshire, Oxfordshire · 7.9 mi · HGVs 2.3% | 25,508 |
| Coldharbour Way to A41(T) Buckinghamshire · 1.2 mi · HGVs 2.5% | 23,003 |
| A4129 to A329 Oxfordshire, Buckinghamshire · 1.3 mi · HGVs 6.5% | 17,568 |
| A40 to M40 Oxfordshire · 0.6 mi · HGVs 6.0% | 15,683 |
| A505 to Rowsham Rd, Aylesbury Central Bedfordshire, Buckinghamshire · 8.0 mi · HGVs 6.5% | 14,453 |
| A41 / A413 to A4157 Buckinghamshire · 0.6 mi · HGVs 1.8% | 14,450 |
| A329 to A40 Oxfordshire · 3.8 mi · HGVs 6.3% | 11,601 |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Route
Central Bedfordshire to Oxfordshire · 23.8 miles
A418 traffic and collisions by section
8 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
| # | |||
|---|---|---|---|
| 1 | A505 to Rowsham Rd, AylesburyCentral Bedfordshire, Buckinghamshire | 14,453 | 24 |
| 2 | A41 / A413 to A4157Buckinghamshire | 14,450 | 15 |
| 3 | A41W to A41 / A418Buckinghamshire | 27,293 | fewer than 3 |
| 4 | Coldharbour Way to A41(T)Buckinghamshire | 23,003 | 15 |
| 5 | Coldharbour Way, Aylesbury to A4129Buckinghamshire, Oxfordshire | 25,508 | 45 |
| 6 | A4129 to A329Oxfordshire, Buckinghamshire | 17,568 | fewer than 3 |
| 7 | A329 to A40Oxfordshire | 11,601 | 9 |
| 8 | A40 to M40Oxfordshire | 15,683 | 14 |
Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the A418 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.
A418 traffic by vehicle type
Cars and taxis make up 79.1% of the vehicle miles on the A418. HGVs account for 4.1%, rising to 6.5% on A505 to Rowsham Rd, Aylesbury.
Vehicle mix, 2025
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
HGV share of traffic
| Year | HGV share |
|---|---|
| 2000 | 5.3% |
| 2001 | 4.6% |
| 2002 | 5.7% |
| 2003 | 5.4% |
| 2004 | 5.3% |
| 2005 | 5.1% |
| 2006 | 4.4% |
| 2007 | 4.6% |
| 2008 | 4.0% |
| 2009 | 3.8% |
| 2010 | 3.7% |
| 2011 | 3.7% |
| 2012 | 3.9% |
| 2013 | 3.9% |
| 2014 | 3.8% |
| 2015 | 3.9% |
| 2016 | 3.8% |
| 2017 | 4.0% |
| 2018 | 4.1% |
| 2019 | 4.0% |
| 2020 | 4.8% |
| 2021 | 4.8% |
| 2022 | 4.6% |
| 2023 | 4.5% |
| 2024 | 4.4% |
| 2025 | 4.1% |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
A418 traffic trend
Traffic on the A418 came to 161 million vehicle miles in 2025. At the count points present in both years, it is down 2.2% on 2019, before the pandemic, and down 6.6% on 2015.
Vehicle miles a year
Like for like, traffic is down 5.3% on 2000.
| Year | Vehicle miles |
|---|---|
| 2000 | 144m |
| 2001 | 147m |
| 2002 | 151m |
| 2003 | 144m |
| 2004 | 154m |
| 2005 | 155m |
| 2006 | 155m |
| 2007 | 154m |
| 2008 | 152m |
| 2009 | 150m |
| 2010 | 145m |
| 2011 | 145m |
| 2012 | 144m |
| 2013 | 144m |
| 2014 | 148m |
| 2015 | 153m |
| 2016 | 160m |
| 2017 | 150m |
| 2018 | 151m |
| 2019 | 153m |
| 2020 | 116m |
| 2021 | 130m |
| 2022 | 143m |
| 2023 | 146m |
| 2024 | 148m |
| 2025 | 161m |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Average daily flow
| Year | Vehicles a day |
|---|---|
| 2000 | 16,976 |
| 2001 | 17,290 |
| 2002 | 17,767 |
| 2003 | 16,925 |
| 2004 | 18,111 |
| 2005 | 17,923 |
| 2006 | 17,970 |
| 2007 | 17,821 |
| 2008 | 17,824 |
| 2009 | 17,609 |
| 2010 | 16,988 |
| 2011 | 17,000 |
| 2012 | 16,975 |
| 2013 | 16,947 |
| 2014 | 17,448 |
| 2015 | 17,979 |
| 2016 | 18,839 |
| 2017 | 18,059 |
| 2018 | 18,085 |
| 2019 | 18,108 |
| 2020 | 13,712 |
| 2021 | 15,366 |
| 2022 | 16,082 |
| 2023 | 16,474 |
| 2024 | 16,678 |
| 2025 | 18,515 |
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 (29.8% of today’s road for 2019). In 2025, 4 of the 12 count points were counted; DfT estimated the rest from earlier counts and local trends.
A418 collisions
Police recorded 126 collisions with the A418 as the first road from 2021 to 2025, 37 of them fatal or serious, including 3 fatal. That is 17.3 per 100 million vehicle miles, lower than the 31.5 for all A-roads in Great Britain. On average there were 1.1 a year for each mile of road.
Reported collisions by year
Down 14.3% from 2021 to 2025.
| Year | Slight | Fatal or serious |
|---|---|---|
| 2021 | 21 | 7 |
| 2022 | 13 | 8 |
| 2023 | 21 | 13 |
| 2024 | 13 | 6 |
| 2025 | 20 | 4 |
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 |
|---|---|
| Coldharbour Way to A41(T) Buckinghamshire · 15 collisions | 148.9 |
| A41 / A413 to A4157 Buckinghamshire · 15 collisions | 93.3 |
| A40 to M40 Oxfordshire · 14 collisions | 84.7 |
| Coldharbour Way, Aylesbury to A4129 Buckinghamshire, Oxfordshire · 45 collisions | 56.5 |
| A505 to Rowsham Rd, Aylesbury Central Bedfordshire, Buckinghamshire · 24 collisions | 51.2 |
Source:DfT STATS19,UK Motoring analysis 2021 to 2025 Updated
A further 17 collisions were recorded at junctions where the A418 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 A418
In route order. Each is the highway authority DfT files the count points under.
- Central Bedfordshire
- Buckinghamshire
- Oxfordshire
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 | 12 count points in 2025 | 15 September 2026 |
| Reported collisions | Road safety open data (STATS19) Department for Transport Derived statistics UK Motoring | 2021 to 2025 | 126 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.