Marshall Group, the multi-facted business based in Cambridge UK, broke through the £1bn barrier in terms of sales last year for the first time – pushing it into the top half of the Sunday Times BDO Top Track 100, published this weekend.

It joins Huntingdon-based Anglian Water in the top half, and together the two companies employ more than 11,000 staff, have combined sales of £2.4bn and profits of £732m.

Now in its 11th year, the league table ranks Britain’s 100 private companies with the biggest sales.

First established more than 100 years ago, Marshall Group is involved in activities as diverse as private jet chartering, aerospace engineering and car sales. It climbed six places in the league table having grown sales 13% to £1bn in 2011.

Anglian Water was taken private in late 2006 in a £2.2bn deal backed by Osprey Acquisitions, a consortium including Canadian and Australian institutional investors and private equity house 3i. Sales grew 1% to £1.4bn, but profits dropped 1.6% to £696m in the year to March 2010. Debt remains considerable at £6bn.

Richard Kelly, partner and head of East England at BDO, title sponsor of the league table, said: “Despite concerns over the health of the national economy, the strong performance of the biggest private companies in East England shows what can be achieved by management teams that have clear vision and ambition.

“The companies have proven their resilience and adaptability, against a backdrop of the eurozone crisis and reduced credit availability. By delivering a service-led approach in their markets, they continue to generate the growth so keenly needed.”