The legal sector has been given a welcome boost after new figures showed a sharp rise in income among leading firms.

The top 100 have reported an average revenue increase of nearly 10% for the second quarter ended 31 October. A survey by Deloitte showed that revenue grew 9.8% on the same period last year, on the back of a first quarter increase of 4%.

The rise also reflects increasing market confidence, as the sector emerges from the financial crisis and a period of mass redundancies. Buoyant firms are now predicting revenue increases of 6.2% for the financial year as a whole. Higher revenues are reflected in an average increase in headcount and average revenue per fee earner, up by 3.9% and 5.7% respectively.

The second quarter’s strong performance came largely through billing more domestic work, with almost four-fifths of fee income derived from the UK.

But the revenue boost did not apply to all firms in the survey: Deloitte reported sharp variability in performance, with some firms seeing a fall and others posting up to 20% rises.

Jeremy Black, partner in Deloitte’s professional services group, said: ‘It is pleasing to see strong growth returning to the UK legal sector and renewed optimism in the domestic market, after an extended period of challenging conditions. However, whilst firms are relatively positive about the next six months continued uncertainty in the markets means a degree of caution is needed.’