Motorway
M275 traffic and collisions
The M275 is a motorway of 2.7 miles, in Portsmouth. This page covers its traffic at 5 DfT count points since 2000 and the collisions police recorded on it.
- Traffic in 2025 70m vehicle miles
- Average daily traffic 71,021 vehicles a day, both directions
- Busiest section 86,395 start of principal section to M275 split
- HGV share 2.1% of vehicle miles
- Traffic since 2019 +1.2% same count points
How busy is the M275?
On an average day in 2025, 71,021 vehicles passed each point on the M275, counting both directions. The busiest section is start of principal section to M275 split (Portsmouth), with 86,395 a day; the quietest listed is M27 to end of Principal section, with 86,395.
Busiest sections, 2025
start of principal section to M275 split carries 1.2 times the road’s average flow.
| Section | Vehicles a day |
|---|---|
| start of principal section to M275 split Portsmouth · 0.5 mi · HGVs 2.2% | 86,395 |
| M27 to end of Principal section Portsmouth · 1.2 mi · HGVs 2.2% | 86,395 |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Route
In Portsmouth · 2.7 miles
M275 traffic and collisions by section
4 sections between junctions, in route order. Each is the average of its DfT count points, weighted by length. 1 short link roads and spurs (0.4 miles) count in the road’s totals but are not listed.
Sections Tap a column heading to sort
| # | |||
|---|---|---|---|
| 1 | M275 to M27Portsmouth | 43,198 | – |
| 2 | start of principal section to M275 splitPortsmouth | 86,395 | – |
| 3 | M27 to end of Principal sectionPortsmouth | 86,395 | – |
| 4 | A3 to A3 / A2047Portsmouth | 51,631 | – |
Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the M275 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.
M275 traffic by vehicle type
Cars and taxis make up 84.6% of the vehicle miles on the M275. HGVs account for 2.1%.
Vehicle mix, 2025
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
HGV share of traffic
| Year | HGV share |
|---|---|
| 2000 | 3.1% |
| 2001 | 3.2% |
| 2002 | 3.0% |
| 2003 | 2.9% |
| 2004 | 3.1% |
| 2005 | 3.0% |
| 2006 | 3.0% |
| 2007 | 2.9% |
| 2008 | 2.6% |
| 2009 | 2.4% |
| 2010 | 2.6% |
| 2011 | 2.5% |
| 2012 | 2.8% |
| 2013 | 2.7% |
| 2014 | 3.3% |
| 2015 | 3.4% |
| 2016 | 2.8% |
| 2017 | 2.4% |
| 2018 | 2.5% |
| 2019 | 2.3% |
| 2020 | 2.5% |
| 2021 | 2.4% |
| 2022 | 2.2% |
| 2023 | 2.2% |
| 2024 | 2.4% |
| 2025 | 2.1% |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
M275 traffic trend
Traffic on the M275 came to 70 million vehicle miles in 2025. At the count points present in both years, it is up 1.2% on 2019, before the pandemic, and up 5.5% on 2015.
Vehicle miles a year
Like for like, traffic is up 1.2% on 2000.
| Year | Vehicle miles |
|---|---|
| 2000 | 69m |
| 2001 | 65m |
| 2002 | 67m |
| 2003 | 66m |
| 2004 | 68m |
| 2005 | 68m |
| 2006 | 70m |
| 2007 | 71m |
| 2008 | 64m |
| 2009 | 64m |
| 2010 | 70m |
| 2011 | 71m |
| 2012 | 70m |
| 2013 | 72m |
| 2014 | 68m |
| 2015 | 69m |
| 2016 | 79m |
| 2017 | 71m |
| 2018 | 70m |
| 2019 | 71m |
| 2020 | 58m |
| 2021 | 65m |
| 2022 | 68m |
| 2023 | 69m |
| 2024 | 60m |
| 2025 | 70m |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Average daily flow
| Year | Vehicles a day |
|---|---|
| 2000 | 67,222 |
| 2001 | 63,971 |
| 2002 | 65,593 |
| 2003 | 64,517 |
| 2004 | 66,095 |
| 2005 | 66,211 |
| 2006 | 68,832 |
| 2007 | 69,520 |
| 2008 | 62,754 |
| 2009 | 62,246 |
| 2010 | 68,186 |
| 2011 | 69,262 |
| 2012 | 68,874 |
| 2013 | 70,017 |
| 2014 | 66,515 |
| 2015 | 67,253 |
| 2016 | 77,001 |
| 2017 | 69,295 |
| 2018 | 68,789 |
| 2019 | 69,306 |
| 2020 | 57,096 |
| 2021 | 63,212 |
| 2022 | 69,065 |
| 2023 | 70,237 |
| 2024 | 60,655 |
| 2025 | 71,021 |
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, 2 of the 5 count points were counted; DfT estimated the rest from earlier counts and local trends.
M275 collisions
Police recorded fewer than 3 collisions with the M275 as the first road from 2021 to 2025, fewer than 3 of them fatal or serious.
Reported collisions by year
| Year | Collisions | Fatal or serious |
|---|---|---|
| 2021 | fewer than 3 | 0 |
| 2022 | 8 | fewer than 3 |
| 2023 | 14 | 0 |
| 2024 | 5 | 0 |
| 2025 | 4 | 0 |
Source:DfT STATS19,UK Motoring analysis 2021 to 2025 Updated
A further 4 collisions were recorded at junctions where the M275 was the second road; they are not in the figures above. Fatal or serious uses DfT’s adjusted serious figures. 66.7% of the collisions could be placed on a section. How we count collisions
Council areas on the M275
In route order. Each is the highway authority DfT files the count points under.
- Portsmouth
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 | 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 | 33 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.