Home / Blog / Research
GalimAI Research - Contagion

Carillion’s collapse and the subcontractor insolvency wave: a GalimAI data study

By GalimAI · Updated 7 June 2026 · 10 min read

When Carillion was liquidated in January 2018 it was not just one big failure — it was a detonation that ran down the supply chain. The most instructive part is how a single insolvency forced hundreds of smaller, otherwise-viable companies under. GalimAI’s data is built to see exactly this kind of linked exposure: who is connected to whom, and where one company’s strain becomes another’s.

£7bn
owed when Carillion collapsed, vs £29m cash
30,000
suppliers and subcontractors exposed
780
construction insolvencies in Q1 2018, +20% YoY
How GalimAI sees this. This study is built on GalimAI’s own data. GalimAI joins Companies House, HM Land Registry and The Gazette into a single live map of the UK property market — 463,022 property-owning companies and more than 1,000,000 owners across England and Wales, each company linked to its named directors, its full filing and charge history, what it owns, how it is financed, and the distress signals around it: insolvency and winding-up notices, mortgage charges and bridging exposure, and dissolution activity. Carillion is the clearest case of contagion: one collapse cascading into hundreds of subcontractor insolvencies — the linked exposure GalimAI’s company-and-director map is designed to reveal. The public figures in this study set the scene; the GalimAI figures are what only our data can show.

What GalimAI’s own data reveals

A failure like Carillion does its damage through connections. GalimAI maps 463,022 property-owning companies and ties each to its named directors, its charges and its distress markers — the raw material for seeing how strain travels. The companies that failed in 2018 were rarely the weakest on paper; they were the ones over-exposed to a single counterparty that stopped paying.

That is what makes the GalimAI map useful beyond a headcount. Our analyses of stacked distress signals, accelerating dissolutions and the regional distress map turn linked, second-order risk into something visible — the kind of concentration that turns one big insolvency into many small ones.

What happened: the Carillion collapse, in plain terms

Carillion entered compulsory liquidation on 15 January 2018 owing close to £7bn against just £29m of cash. As a major government contractor it sat at the top of a vast supply chain — more than 30,000 suppliers and subcontractors were exposed to its failure.

The contagion was immediate. Construction insolvencies in the first quarter of 2018 jumped to around 780, up a fifth on the same period in 2017, with specialist subcontractors hit hardest. Total construction insolvencies for 2018 rose about 13% to 2,954, with analysts attributing much of the spike to Carillion’s fallout.

The public backdrop

IndicatorFigureNote
Debt at collapse~£7bnAgainst ~£29m cash
Suppliers exposed30,000+Top of a deep supply chain
Q1 2018 construction insolvencies~780 (+20% YoY)Subcontractors worst hit
2018 total2,954 (+13%)Fallout attributed to Carillion

The lesson is concentration risk: a company’s health depends on who it depends on. GalimAI’s map is where that dependency becomes legible — the directors, charges and signals that show where a counterparty failure would land.

The most plausible mechanism

The channel is counterparty exposure. When a large payer stops paying, subcontractors carrying that work lose receivables they cannot replace, and thin margins turn into insolvency within months. The tight timing — a visible Q1 2018 spike immediately after a January collapse — is the signature of contagion rather than coincidence. We read it as a strong, well-evidenced correlation with a clear mechanism, while noting that many affected firms were already thinly capitalised.

Correlation, not proof. A supplier’s failure after a client collapse reflects its own capitalisation and concentration as well as the trigger event. We set out the timing, the figures and the most plausible mechanism, but a single policy or event rarely explains an outcome on its own. This is general information, not legal, financial or tax advice; figures are current for 2026 and change over time.

Sources

The proprietary figures in this study (the 463,022 companies, 1,000,000+ owners and the distress signals) are GalimAI first-party data. The public background figures are drawn from:

Frequently asked questions

What did Carillion's collapse do to subcontractors?

It triggered a wave of failures down its supply chain. Construction insolvencies in Q1 2018 rose about 20% year on year to roughly 780, with specialist subcontractors hardest hit, and the 2018 total rose 13% to 2,954.

How big was Carillion's failure?

Carillion was liquidated in January 2018 owing close to £7bn against about £29m of cash, with more than 30,000 suppliers and subcontractors exposed.

What does GalimAI's data add?

GalimAI maps 463,022 property-owning companies linked to their directors, charges and distress signals - the connections through which a single failure spreads. That turns second-order, supply-chain risk into something you can see in advance.

Did Carillion cause the 2018 insolvency spike?

The timing and counterparty mechanism line up tightly - a Q1 spike immediately after a January collapse - making it a strong, well-evidenced correlation. Many affected firms were also thinly capitalised, so it was rarely the only factor.

Map supply-chain exposure in GalimAI

GalimAI links 463,022 property-owning companies to their directors, charges and distress signals - the supply-chain strain a single failure spreads. Search free.

Search the portal free More research