AI companies took a record 44% of UK smaller-business equity value in 2025, from a market that shrank 4% to GBP12.3bn, the British Business Bank (BBB), the UK government's development bank, reported on 2 July 2026 1. AI investment rose 48% over the year while every other sector contracted in both share and cash. The top 10 fundraisings absorbed 23% of all investment, the highest concentration since 2020, and seed deals fell 27%.
The BBB's chief investment officer, Leandros Kalisperas, said the concentration into AI reflects both the scale of the opportunity and the challenges across the wider market 2. The tracker measures the value of equity raised, not the number of companies funded, so a record share can sit on top of fewer names taking larger cheques.
A 48% rise in AI money against a 4% fall in the total meant growth-stage rounds pulled capital up and out of everything beneath them. The same barbell shape carried PhysicsX to a $300m round at a $2.4bn valuation in June . Fewer companies, larger cheques, one sector.
