Trunk A-road
A78 traffic and collisions
The A78 is a trunk A-road of 42.5 miles, from Inverclyde to South Ayrshire. This page covers its traffic at 18 DfT count points since 2000 and the collisions police recorded on it.
- Traffic in 2025 231m vehicle miles
- Average daily traffic 14,879 vehicles a day, both directions
- Busiest section 34,226 A738 to A737
- HGV share 3.4% of vehicle miles
- Traffic since 2019 −5.2% same count points
- Collisions, 2021 to 2025 102 9.1 per 100m vehicle miles
How busy is the A78?
On an average day in 2025, 14,879 vehicles passed each point on the A78, counting both directions. The busiest section is A738 to A737 (North Ayrshire), with 34,226 a day; the quietest listed is roundabout at Southannan Sands coal terminal to B7048, with 7,269.
Busiest sections, 2025
A738 to A737 carries 2.3 times the road’s average flow.
| Section | Vehicles a day |
|---|---|
| A738 to A737 North Ayrshire · 2.4 mi · HGVs 4.4% | 34,226 |
| A737 to A71 North Ayrshire · 3.2 mi · HGVs 2.9% | 32,804 |
| A79 to A77 South Ayrshire · 0.8 mi · HGVs 3.6% | 24,012 |
| B746 mid-junction to A79 South Ayrshire · 1.2 mi · HGVs 4.1% | 23,779 |
| A71 to A737 North Ayrshire · 1.2 mi · HGVs 4.5% | 19,938 |
| A759 to B746 mid-junction South Ayrshire · 2.2 mi · HGVs 4.7% | 19,618 |
| B7080 to A759 North Ayrshire · 1.8 mi · HGVs 4.4% | 19,469 |
| B7025 Bath Street to A760 North Ayrshire · 0.8 mi · HGVs 1.6% | 13,588 |
| A770 Inverclyde · 5.2 mi · HGVs 1.2% | 13,334 |
| A738 - Eglinton Road to A738 North Ayrshire · 4.1 mi · HGVs 5.1% | 12,428 |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Route
Inverclyde to South Ayrshire · 42.5 miles
A78 traffic and collisions by section
17 sections between junctions, in route order. Each is the average of its DfT count points, weighted by length.
Show all 17 sections Tap a column heading to sort
| # | |||
|---|---|---|---|
| 1 | A770Inverclyde | 13,334 | 19 |
| 2 | A770 to Routenburn Rd, LargsInverclyde, North Ayrshire | 7,893 | 17 |
| 3 | Routenburn Rd to B7025 Bath StreetNorth Ayrshire | 8,287 | 3 |
| 4 | B7025 Bath Street to A760North Ayrshire | 13,588 | 3 |
| 5 | A760 to roundabout at Southannan Sands coal terminalNorth Ayrshire | 8,794 | 3 |
| 6 | roundabout at Southannan Sands coal terminal to B7048North Ayrshire | 7,269 | 3 |
| 7 | B7048 to B7047 Chapelton RoadNorth Ayrshire | 7,920 | 3 |
| 8 | B7047 Chapelton Road to Road to Ardrossan CastleNorth Ayrshire | 12,413 | 11 |
| 9 | A738 - Eglinton Road to A738North Ayrshire | 12,428 | 5 |
| 10 | A738 to A737North Ayrshire | 34,226 | 11 |
| 11 | A737 to A71North Ayrshire | 32,804 | 10 |
| 12 | A71 to A737North Ayrshire | 19,938 | 0 |
| 13 | B7080 to A759North Ayrshire | 19,469 | fewer than 3 |
| 14 | At A759South Ayrshire | 19,469 | 0 |
| 15 | A759 to B746 mid-junctionSouth Ayrshire | 19,618 | 3 |
| 16 | B746 mid-junction to A79South Ayrshire | 23,779 | 3 |
| 17 | A79 to A77South Ayrshire | 24,012 | 6 |
Vehicles a day is the average daily flow in 2025. “Since 2019” compares the same count points. Collisions are those with the A78 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.
A78 traffic by vehicle type
Cars and taxis make up 80.7% of the vehicle miles on the A78. HGVs account for 3.4%, rising to 6.3% on A760 to roundabout at Southannan Sands coal terminal.
Vehicle mix, 2025
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
HGV share of traffic
| Year | HGV share |
|---|---|
| 2000 | 4.1% |
| 2001 | 4.0% |
| 2002 | 4.7% |
| 2003 | 4.9% |
| 2004 | 5.2% |
| 2005 | 5.3% |
| 2006 | 5.1% |
| 2007 | 4.7% |
| 2008 | 4.7% |
| 2009 | 4.3% |
| 2010 | 4.4% |
| 2011 | 4.3% |
| 2012 | 4.3% |
| 2013 | 4.4% |
| 2014 | 4.2% |
| 2015 | 4.3% |
| 2016 | 4.1% |
| 2017 | 4.0% |
| 2018 | 4.1% |
| 2019 | 4.0% |
| 2020 | 4.5% |
| 2021 | 3.9% |
| 2022 | 3.6% |
| 2023 | 3.5% |
| 2024 | 3.4% |
| 2025 | 3.4% |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
A78 traffic trend
Traffic on the A78 came to 231 million vehicle miles in 2025. At the count points present in both years, it is down 5.2% on 2019, before the pandemic, and down 7.6% on 2015.
Vehicle miles a year
Like for like, traffic is up 8.9% on 2000.
| Year | Vehicle miles |
|---|---|
| 2000 | 221m |
| 2001 | 219m |
| 2002 | 215m |
| 2003 | 219m |
| 2004 | 228m |
| 2005 | 216m |
| 2006 | 245m |
| 2007 | 250m |
| 2008 | 252m |
| 2009 | 249m |
| 2010 | 243m |
| 2011 | 241m |
| 2012 | 237m |
| 2013 | 235m |
| 2014 | 241m |
| 2015 | 244m |
| 2016 | 251m |
| 2017 | 240m |
| 2018 | 241m |
| 2019 | 244m |
| 2020 | 181m |
| 2021 | 213m |
| 2022 | 222m |
| 2023 | 226m |
| 2024 | 224m |
| 2025 | 231m |
Source:DfT,UK Motoring analysis 2000 to 2025 Updated
Average daily flow
| Year | Vehicles a day |
|---|---|
| 2000 | 14,558 |
| 2001 | 14,444 |
| 2002 | 14,855 |
| 2003 | 15,139 |
| 2004 | 15,698 |
| 2005 | 15,912 |
| 2006 | 16,307 |
| 2007 | 16,695 |
| 2008 | 16,763 |
| 2009 | 16,614 |
| 2010 | 16,196 |
| 2011 | 16,060 |
| 2012 | 15,763 |
| 2013 | 15,690 |
| 2014 | 16,057 |
| 2015 | 16,257 |
| 2016 | 16,742 |
| 2017 | 15,928 |
| 2018 | 15,622 |
| 2019 | 15,772 |
| 2020 | 11,650 |
| 2021 | 13,699 |
| 2022 | 14,313 |
| 2023 | 14,561 |
| 2024 | 14,465 |
| 2025 | 14,879 |
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 (87.8% of today’s road for 2019). In 2025, 12 of the 18 count points were counted; DfT estimated the rest from earlier counts and local trends.
A78 collisions
Police recorded 102 collisions with the A78 as the first road from 2021 to 2025, 53 of them fatal or serious. That is 9.1 per 100 million vehicle miles, lower than the 31.5 for all A-roads in Great Britain. On average there were 0.5 a year for each mile of road.
Reported collisions by year
Down 46.2% from 2021 to 2025.
| Year | Slight | Fatal or serious |
|---|---|---|
| 2021 | 15 | 11 |
| 2022 | 11 | 13 |
| 2023 | 9 | 11 |
| 2024 | 7 | 11 |
| 2025 | 7 | 7 |
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 |
|---|---|
| B7047 Chapelton Road to Road to Ardrossan Castle North Ayrshire · 11 collisions | 32.7 |
| A770 Inverclyde · 19 collisions | 14.0 |
| A770 to Routenburn Rd, Largs Inverclyde, North Ayrshire · 17 collisions | 13.0 |
| A738 to A737 North Ayrshire · 11 collisions | 7.6 |
| A737 to A71 North Ayrshire · 10 collisions | 5.5 |
Source:DfT STATS19,UK Motoring analysis 2021 to 2025 Updated
A further 5 collisions were recorded at junctions where the A78 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 A78
In route order. Each is the highway authority DfT files the count points under.
- Inverclyde
- North Ayrshire
- South Ayrshire
Roadworks on the A78 in Scotland
The Scottish Road Works Register lists 34 sets of roadworks on the A78 in Scotland, 0 of them under way. 26 close the road, a lane or a slip road. From the extract of 16 September 2026.
-
A78t Kilwinning Bypass From Pennyburn Roundabout To Eglinton Interchange
-
A78t Greenock Road Largs To Shore Road Skelmorlie
-
A78t Irvine Bypass From Eglinton Interchange To Warrix Interchange
-
A78t Main Road Fairlie To Irvine Road Largs
-
A78t Kilwinning Bypass From Pennyburn Roundabout To Eglinton Interchange
-
A78t Irvine Bypass From Warrix Interchange To Newhouse Interchange
Works in Scotland only, and only where the register records them against the road number. The register publishes one extract a day, so works can start, finish or change after it is taken. Roadworks across Scotland
Source:SRWR Extract of 2026-09-16 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 | 18 count points in 2025 | 15 September 2026 |
| Reported collisions | Road safety open data (STATS19) Department for Transport Derived statistics UK Motoring | 2021 to 2025 | 102 reported collisions | 15 September 2026 |
| Roadworks | Scottish Road Works Register open data Scottish Road Works Commissioner | Extract of 2026-09-16 | 22,074 sets of roadworks recorded in Scotland | 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.