Revenues in the UK's biggest law firm look heather this year, and the most successful firms now look to international markets and global mergers to grow profits and reach new jurisdictions.

Revenues at the top 100 UK law firms rose by 13 per cent this year, reaching £15.5bn, according to the newly published Legal Business 100. 

The top 10 law firms saw an increase of average net income in 2010-11, compared to a fall in net income of 3.5 per cent for the previous year, the new figures reveal. 

DLA Piper sits in the top spot on the table, with global revenues of £1.25bn, edging it past Global Elite firms Clifford Chance (£1.22bn), Linklaters (£1.2bn), Freshfields Bruckhaus Deringer (£1.14bn) and Allen & Overy (£1.12bn).

Hogan Lovells also entered the £1bn club, with the merger between Washington DC-based Hogan & Hartson and legacy London firm Lovells now over a year old, says Legal Business 100. 

Norton Rose inched closer to this exclusive group and the top of the table after merging with firms in Australia, Canada and South Africa.

The biggest profit margin was at Slaughter & May at 49 per cent, on a turnover of £440m.

DLA Piper’s top partners earned an average of £2.5m in 2011 – up a staggering £1m from last year’s figure, and though gains at the rest of the top ten earners were more modest, only three of the highest pay packets among the top ten firms decreased.

But while DLA is the biggest UK law firm by worldwide revenue, just 22 per cent of its billings originate in the UK. By Uk billings it is just inside the top 10. 

By  breakdown of UK revenue, reports Legal Business, Linklaters is the highest earner. it booked a UK turnover of £510.4m, up three per cent from last year.