The State of UK Traffic Noise, 2026

The headline picture

In 2025, the busiest single traffic-count location in Britain — on the M25 in Hillingdon, west London — recorded over 212,000 motor vehicles a day. Nationally, traffic at matched count points rose 1.5% on 2024, but is roughly flat against 2019, before the pandemic. HGVs make up 5.1% of traffic nationally, but on some freight corridors near major ports, nearly half of all vehicles are HGVs — the vehicle type that matters most for noise.

This is AcoustaPLOT's first annual read of the UK's official road traffic count data, built to give property buyers, journalists and local campaigners a genuine, sourced answer to "where is traffic noise actually worst" — rather than a guess.

The busiest roads in Britain

Motorways dominate, as you'd expect. The single busiest count point in the country in 2025 sat on the M25 in Hillingdon, at over 212,000 vehicles a day — closely followed by other M25 points in Surrey and Buckinghamshire, and Manchester's M60 in Salford, all above 190,000.

Averaged across every count point on each road, the M25 is Britain's busiest motorway overall (an average of roughly 133,000 vehicles a day across its 51 counted points in 2025), ahead of Manchester's M60 orbital (around 125,000) and the M1 (around 98,000). The M56, M27, M62, M6, M4 and M5 all averaged comfortably above 85,000 vehicles a day at their counted points.

Which regions carry the most traffic

By average traffic per count point, London tops the regional table (around 21,800 vehicles a day per point in 2025), followed by the South East (around 20,900) and the North West (around 20,000). At the other end, Scotland and Wales have the lowest average traffic per point (around 12,500 and 13,200 respectively) — but that isn't the whole story: Scotland's count points cover by far the longest combined road length of any region in the dataset, reflecting its more dispersed, rural road network rather than genuinely quiet roads everywhere.

That distinction matters for anyone reading a regional "average" figure: a low average per point can mean either lighter traffic, or simply a network with proportionally more minor rural roads pulling the average down. We'd caution against reading it as a simple noise-exposure league table without that context.

Local authorities where traffic is heaviest

Among local authorities with at least 10 count points, Slough has the highest average traffic per point in 2025 (around 41,500 vehicles a day), just ahead of Newport (around 41,200) and the London boroughs of Havering (around 37,500) and Redbridge (around 33,700). Bury, Tower Hamlets, Hillingdon, Portsmouth, Solihull and Warrington all follow close behind — a mix of motorway-orbital boroughs, port/logistics towns and dense outer-London authorities, rather than any single obvious pattern.

The quietest places, by the same measure

At the other end of the same local-authority ranking, the pattern flips almost entirely to remote and island authorities. Comhairle nan Eilean Siar (the Outer Hebrides) has the lowest average traffic per count point of any local authority with at least 10 points in 2025, at around 1,700 vehicles a day, followed by Orkney (around 2,200) and Shetland (around 2,800). Argyll & Bute, the Scottish Borders, Powys, Highland and Ceredigion — all large, sparsely populated rural or island authorities — round out the quietest eight of the 206 local authorities with enough count points to average meaningfully.

That isn't a surprising result, but it's a useful sanity check on the numbers above: the quietest authorities by this measure aren't quiet suburbs, they're places where the road network itself is thin and rural. It's exactly the same caveat as the regional figures earlier — a low average can mean genuinely light traffic, or it can mean a network of mostly minor roads pulling the average down, and telling the two apart matters more than the ranking itself.

How a typical suburban A-road compares

Not every property near a classified road sits near a motorway or a regional trunk route, so it's worth putting an ordinary A-road into the same context. Among the 16,667 A-road count points recorded in 2025, the median daily flow is around 13,700 vehicles and the mean — pulled upward by the busiest routes — is around 17,700; a wide range sits either side of both.

A count point carrying around 16,000 vehicles a day sits close to the middle of that distribution, at roughly the 60th percentile nationally: busier than the typical A-road, but far from exceptional, and nowhere near the HGV-heavy freight corridors or motorway-adjacent points discussed above. It's the kind of figure this dataset is best at putting into context — a number that can sound significant taken on its own reads quite differently once it's placed against the roughly 16,700 other A-road count points measured the same way, in the same year.

The HGV angle: why volume alone understates the noise problem

Total vehicle volume is only part of the noise story. HGVs generate substantially more noise per vehicle than cars — from engine and exhaust noise, tyre roar and braking — and that difference is most audible at night and on gradients, which is exactly why we track the HGV share separately, not just the headline traffic figure.

Nationally, HGVs made up 5.1% of all motor vehicles at count points in 2025, a slight fall from 5.5% in 2019 on the same matched set of points. But that national average hides real local extremes. The A160 and M180 corridor around the Humber ports in North and North East Lincolnshire — the road network serving Immingham, one of the UK's largest freight ports — had count points where HGVs made up 25–49% of all traffic in 2025, roughly five to ten times the national share. Similar HGV-heavy patterns show up around the A403/A4 near the Severn crossings and Bristol, and on the A74(M) at the Scotland–England border. For anyone assessing noise near these routes, the HGV share is arguably a more useful figure than total vehicle count alone.

Has traffic noise gone up or down since the last count?

Comparing the same count points year to year (rather than all points counted in each year, which changes from year to year) gives the fairest read of genuine change. On that basis, average traffic in 2025 was 1.5% higher than in 2024. Against 2019 — the last full year before the pandemic — 2025 traffic at matched points is about 1% lower, essentially flat over six years, after a sharp real dip during the pandemic itself (matched points fell around 23% between 2019 and 2020) and a gradual recovery since.

In short: nationally, road traffic — and by extension, traffic noise exposure — has not materially worsened since before the pandemic, though it has fully recovered from its 2020 low and is trending very slightly upward year-on-year again.

How we use this at AcoustaPLOT

This national dataset is one of the inputs behind every AcoustaPLOT property report: where Defra's strategic noise maps don't cover a road, we calculate an estimated noise level from this same DfT traffic data, combined with Ordnance Survey terrain data, rather than leaving a property unassessed. Seeing the national patterns — which roads, regions and vehicle mixes carry the most traffic — is also what tells us where that gap-filling approach matters most.

Methodology

This analysis uses the Department for Transport's road traffic count statistics (the AADF — Annual Average Daily Flow — dataset), the same official source behind the UK's national traffic statistics. Our copy covers 600,551 records across 46,754 distinct count points nationally, for every year from 2000 to 2025.

A "count point" is a specific, geolocated point on a road link where the DfT records or estimates daily traffic by vehicle type. Not every count point is physically counted every year: in 2025, of the 22,334 count-point records in our copy of the data, 7,950 (36%) were direct counts and the remaining 14,384 (64%) were estimated by DfT from previous counts and local growth patterns, as is standard for this dataset. We have treated all figures as the DfT publishes them and have not smoothed, filled or extrapolated beyond that.

Coverage is also uneven by road type: major roads (A-roads and motorways) are counted far more densely than minor roads, so figures here — including the regional and local-authority averages — describe the counted road network, not every street in the country. Year-on-year and regional totals summed across all points in a given year are not directly comparable, because the set of points counted changes each year; where we compare change over time, we have used only count points present in both years being compared, as noted above. All figures are drawn directly from the dataset as published; we have not rounded up or extrapolated beyond what it shows.