Money
UK industries became less dominated by big firms between 2010 and 2025, ONS data shows
AI-generated illustration
The top five firms in an average UK industry now take a smaller share of sales than in 2010. New ONS statistics put the weighted five-firm share at 0.38 in 2025, down from 0.45.
0.45 to 0.38Average five-firm concentration ratio, sales-weighted, UK non-financial business economy, 2010 to 2025
The facts
- 1Industry concentration asks how much of an industry's sales go to a few big firms. One measure adds up the share held by the five largest.
- 2The ONS built the new figures from business records it already held, so it did not need to collect new data from firms.
- 3Weighting industries by their sales, the average five-firm share fell from 0.45 to 0.38. The biggest drop came between 2014 and 2017.
- 4The ONS says concentration cannot show by itself how competitive an industry is. Production technology and firms serving different products or regions can also affect it.
- 5Economists pair concentration with business dynamism (firms entering, growing, shrinking and exiting) and price markups. An ONS bulletin on these is due in December 2026.
Why it matters
A lower share for the top five firms does not prove markets are more competitive. It gives economists one measure to compare with turnover of firms and markups when judging competition.
