The A9 dualling project is an ongoing infrastructure project in Scotland to upgrade the A9 between Perth and Inverness from a single carriageway to a dual carriageway. A dual carriageway allows drivers to overtake safely, as they do not have to meet oncoming traffic; and the crash barriers on the central reservation greatly reduce the frequency of head-on collisions. As most of the A9 is currently a single carriageway, drivers may have to overtake heavy goods vehicles (HGVs) and other slow-moving vehicles as they are limited to , lower than the speed limit for cars and motorcycles. The A9 has been dubbed Scotland's most dangerous road. In 2022, there were 17 fatalities, its highest level in 20 years before falling to four in 2023.
The project was announced in 2011 in response to the safety concerns with overtaking and head-on collisions. Construction started in 2015 starting with a section between Kincraig and Dalraddy (near Aviemore) followed by the Luncarty to Pass of Birnam in 2019. This project was originally due to finish in 2025, but has since been delayed to 2035. , two out of eleven sections have been completed, totalling 11 miles (17 km), leaving 77 miles (124 km) to be upgraded. The sections between Tomatin and Moy, as well as between Tay Crossing and Ballinluig are under construction as of November 2025. Both sections are due to be finished in 2028.
History Early upgrades The 110 mile (176 km) section of the A9 between Perth and Inverness was substantially rebuilt between 1972 and 1986. The rebuilt road follows essentially the same route as before except where it bypasses towns and villages instead of running through their centres. At the time of the rebuild, traffic levels were low enough to not warrant a dual carriageway, although provision was given should it be needed. Parts of the road were upgraded to dual carriageway where there are steep gradients or where traffic flows are expected to be high.
The most significant alteration of the A9 route was the realignment of the route north from Inverness, crossing the Moray Firth via the Kessock Bridge, cutting through the Black Isle and back across the Cromarty Firth. This shortened the route by , bypassing Beauly, Muir of Ord and Dingwall. Construction of the Kessock Bridge began in 1976, and was completed in 1982.
Between Perth and Inverness, the road has been dubbed Killer A9, because of accidents and fatalities where dual-carriageway sections merge into a single carriageway; the principal cause is that motorists drive at excessive speeds to overtake lines of slower-moving vehicles before the dual carriageway ends. Dangerous overtaking manoeuvres on long single-carriageway stretches of the road are also common causes of accidents.
Early announcement Since 2007, the Scottish Government has given serious consideration to converting the entire Perth–Inverness section to dual carriageway with more grade separated junctions, with the initial estimated cost at £600 million. In late 2008, the Scottish Government's transport plan for the next 20 years was announced. It brought forward planned improvements to the A9 to try to stimulate the economy and protect jobs. This included a commitment to full dualling of the road between Perth and Inverness. Work costing a total of £8.5 million was undertaken at Moy, Carrbridge and Bankfoot. Northbound overtaking lanes were created and the carriageway was reconstructed at both Moy and Carrbridge. Junction improvements were also made at Moy and at the Ballinluig junction, south of Pitlochry.
Speed cameras and speed limits
In July 2013, the Scottish Government announced a plan to install average speed cameras on the A9 between Perth and Inverness. This was undertaken with an aim to reduce accidents and fatalities on the road, and was the second permanent average speed camera scheme in Scotland. Simultaneously, an increased speed limit for heavy goods vehicles (HGVs) from to was also announced to help mitigate driver frustration. Both became operational in October 2014. However, the 40 mph single carriageway speed limit remains on other single carriageways of Scotland. This was before the single carriageway speed limit for HGVs was increased in England and Wales from 40 to 50mph in 2015. The HGV speed limit for dual carriageways in Scotland remains at 50 mph.
After the Scottish Government proposal to reduce the national speed limit on single carriageways from 60 to 50 mph was rejected, there are proposals to increase the HGV speed limits. This would put it in line with England and Wales, where the single carriageway speed limit will be raised from 40 to 50 mph, and the dual carriageway speed limit from 50 to 60 mph.
The A9 Safety Group claim that the speed cameras have had a "positive influence" on road users, with the number of drivers breaking the speed limit by over decreasing by 97%. Improvements to safety include at least a 40% reduction in fatalities, and this has been attributed, at least in part, to a reduction in speeding, from 1 in 3 vehicles to just 1 in 15. The average speed cameras may be removed after the A9 dualling project is complete. The increased HGV speed limit has led to improved driver behaviour and reduced road deaths and serious injuries by 31% as drivers are less likely to perform dangerous overtaking. It also improves fuel efficiency. +A9 speed limit Perth–Inverness (mph)Cars/motorcycles6070Cars towing trailers5060HGVs5050Buses/coaches5050
Road safety statistics The A9 has been dubbed the most dangerous road in Scotland. In 2022, despite the installation of average speed cameras, 17 people died on the A9, of whom 13 were on the stretch between Perth and Inverness, where much of the route is single carriageway. It also included the deaths of three Americans visiting Scotland in August 2022, where the crash happened in the Highlands. This was the highest number of fatalities in a one-year period over the past 20 years. However, other recent years had few fatalities; there was one death per year between 2019 and 2021, and four deaths in 2023. This FOI (freedom of information) request was posted on 14 May 2024, responded 5 June 2024 before being published on 1 July 2024. Data for 2023 is provisional as of time of posting. Between 2010 and 2022, there were a total of 72 fatalities on the A9 between Perth and Inverness, working out at an average of 5.5 deaths per year. The "A9 Dual Action Group" was established to bring attention to the statistics. It submitted a petition to the Scottish Parliament in December 2022, calling on the Scottish Government to follow through on its 2011 commitment to convert the remaining of single carriageway into dual carriageway by 2025. In 2023, the Scottish National Party (SNP) stated that the dualling of the road would not be complete by 2025.
The annual average daily traffic (AADT) of the A9 varies between Perth and Inverness from 8,500 around Pitlochry, 22,500 around Perth and 37,000 around Inverness.Statistics – Safety/Speed Limits – A9Road Retrieved 10 September 2024
Construction Announcement In November 2011, the Scottish Government announced that it would upgrade the entire road between Perth and Inverness to a dual carriageway by 2025. The design contract was split into three lots with Lot 1 (Glengarry to Dalraddy) awarded to a CH2M / Fairhurst joint venture in April 2014. Lot 2 (Pass of Birnam to Glengarry) was awarded to Jacobs in August 2014 and Lot 3 was awarded to an Atkins / Mouchel joint venture in December 2014. The contract for a preliminary section (outwith Lots 1 to 3) of the £3 billion project was awarded in June 2015. Then transport minister Keith Brown stated that the A9 dualling project would be "the biggest transport project in Scotland's history". Preliminary work started in 2014 in preparation of main construction work.
Completed sections
Work began on the first 5-mile (8 km) section between Kincraig and Dalraddy (located just south of Aviemore) in September 2015. The first section was scheduled to open in the summer of 2017, but due to technical problems, this section suffered a slight delay and completed in September 2017 at a cost of £35 million. It is an isolated stretch of dual carriageway (i.e., this section is not an extension of an existing dual carriageway or something that fills the gap, as was done for the second and third section down below). Since Kincraig to Dalraddy was upgraded, a 2+1 road section (also known as WS2+1) was removed due to CD 109 requirements of the Design Manual for Roads and Bridges (DMRB) requiring a minimum of a 2 km section of single carriageway between the dual carriageway and the WS2+1 section.. The information for readers is located at para 6.4 "Where a roundabout does not provide a direct interface between a WS2+1 road and a dual carriageway, a 2km section of single carriageway shall be provided between the WS2+1 layout and the dual carriageway section".
The second section of the project was the 6-mile (10 km) section between Luncarty and Pass of Birnam, the first section of what was single carriageway north of Perth. After the £96 million contract was awarded to Balfour Beatty in August 2018, construction works began in February 2019. Between September 2017 and February 2019 there were no works in relation with the dualling programme. This section was scheduled to finish in early 2021. Like the Kincraig to Dalraddy section, it experienced a slight delay meaning that this section was finished in August 2021 with off-carriageway works to finish by 2022. After the completion of the first two sections, 11 miles (18 km) of single carriageway had been converted to dual carriageway.
Proposed and under construction sections Between August 2021 and October 2024, no sections of the A9 were upgraded or under construction. The project will be delivered via a hybrid approach, utilising both 'design and build' (D&B) and 'mutual investment model' (MIM), a type of public-private partnership, contracts.
The third section to be upgraded is between Tomatin and Moy, also 6 miles long. This is the northernmost section of single carriageway for the scheme. In November 2023, Transport Minister Fiona Hyslop announced three contractors had been shortlisted for this scheme: John Graham Construction Ltd, Sacyr UK Ltd and Balfour Beatty Civil Engineering Ltd. The £150 million contract was awarded to Balfour Beatty in July 2024. Some preparation works to this section include trees being cut down and a new railway bridge on the Highland Main Line, which were done in 2021 and 2022, ahead of the main construction work. The new railway bridge is also wide enough should the Highland Main Line be doubled in the future. It was initially projected that this section would be upgraded by the end of 2027. Delays due to Belfour Beatty needing to assess the "impact of weather and environmental restrictions around working in rivers and streams" have pushed the completion date to early 2028. Preparatory works on this section began in October 2024, and major construction started in May 2025. The section's cost rose to £308 million from £254 million in July 2024 and before that, £197 million.