RSK–Octavius acquisition: contracting shift and delivery risks for UK project teams
Reviewed by Tom Sullivan
First reported on The Construction Index
30 Second Briefing
RSK has acquired Octavius Infrastructure from Sullivan Street Partners, moving the formerly consultancy-focused group into tier one main contracting across UK rail and highways, with Octavius’ 700 staff retained under chief executive John Dowsett. Octavius reported £322.9m turnover and £8.6m pre-tax profit to 31 March 2025, while RSK turned over £2.24bn but remained loss-making after 11 acquisitions in the year. Current Octavius schemes include Ryde Pier and Waterloo Station roof refurbishments, new stations at Okehampton and Charfield, and the A46 Walsgrave and A140 Long Stratton Bypass upgrades.
Technical Brief
- Octavius originated as the rail and highways division of Geoffrey Osborne before its 2021 carve-out.
- Leadership continuity is explicit: John Dowsett remains CEO, with Matt Smith and Gavin Pritchard heading rail and highways.
- Year-on-year growth is strong, with Octavius turnover rising from £276.7m (2024) to £322.9m (2025).
- Profitability has accelerated, with pre-tax profit increasing from £4.7m to £8.6m over the same period.
- RSK’s group revenue reached £2,241m to 5 April 2025, driven by 11 acquisitions in that year alone.
- Despite scale, RSK recorded a £124.5m pre-tax loss and has remained loss-making since 2017.
Our Take
Within our 32 Infrastructure stories, very few feature a UK contractor like RSK Group combining double‑digit revenue growth with a multi‑year loss‑making profile, which signals an aggressive roll‑up strategy where cash generation from assets such as Octavius is likely critical to stabilising the balance sheet.
Octavius’ £300m‑plus turnover and 700‑strong workforce move RSK into the same competitive space as established tier one players on UK rail and highways frameworks, which could alter bidding dynamics on schemes similar in scale to the A46 Walsgrave and A140 Long Stratton upgrades.
RSK’s 11 acquisitions in a single year stand out in our infrastructure database, suggesting integration risk will be a key execution issue; maintaining Octavius’ recent profitability will likely depend on how quickly RSK can align systems and governance without disrupting live projects such as the Ryde Pier and Colchester link road works.
Prepared by collating external sources, AI-assisted tools, and Geomechanics.io’s proprietary mining database, then reviewed for technical accuracy & edited by our geotechnical team.
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