Fee income at the UK's 10 largest law firms grew by 5.7% in 2015-16, according to new data from professional services firm Deloitte.

The Big Four accountant's latest quarterly law firm survey shows the largest UK firms outpaced their smaller peers.

Firms ranked between 11 and 25 by revenue grew fee income by 1.8% in 2015-16, while those in the 26 to 50 group experienced a 4.3% increase.

Overall, the top 100 grew by 5.4% in the financial year ending 30 April 2016.

The research, which has been published as results have started trickling in from UK firms, found the top 10 achieved average fees per fee earner of £391,000 across the year, compared to £248,000 for the 11 to 25 grouping and £260,000 for the 26 to 50 category.

The fourth quarter (Q4) was particularly strong for the top 10, which grew fee income by 7.2% compared to the same quarter the previous year.

The 11 to 25 group of firms had a poor Q4 with just 0.3% fee income growth year-on-year, compared to a 5.8% increase in the 26-50 group.

Jeremy Black, a partner in Deloitte's professional practices group, said: "The fact that the average fees per fee earner in the 26 to 50 category was higher than that achieved in the 11 to 25 category is a clear sign of the changing dynamics within the sector."

He added: "Over the last couple of years, merger activity in the sector and large differences in the growth rates achieved by firms, along with changes in business models and technology, have had a significant impact on what has historically been a relatively stable sector."

Deloitte ascribed the increase in fee income across the top 100 to a 2.6% rise in fee earner headcount and an increase in the average rate per fee earner that firms were able to recover.

Top 100 firms are forecasting a growth of 4% in fee income for the year ahead.

Fee income at the UK's 10 largest law firms grew by 5.7% in 2015-16, according to new data from professional services firm Deloitte.

The Big Four accountant's latest quarterly law firm survey shows the largest UK firms outpaced their smaller peers.

Firms ranked between 11 and 25 by revenue grew fee income by 1.8% in 2015-16, while those in the 26 to 50 group experienced a 4.3% increase.

Overall, the top 100 grew by 5.4% in the financial year ending 30 April 2016.

The research, which has been published as results have started trickling in from UK firms, found the top 10 achieved average fees per fee earner of £391,000 across the year, compared to £248,000 for the 11 to 25 grouping and £260,000 for the 26 to 50 category.

The fourth quarter (Q4) was particularly strong for the top 10, which grew fee income by 7.2% compared to the same quarter the previous year.

The 11 to 25 group of firms had a poor Q4 with just 0.3% fee income growth year-on-year, compared to a 5.8% increase in the 26-50 group.

Jeremy Black, a partner in Deloitte's professional practices group, said: "The fact that the average fees per fee earner in the 26 to 50 category was higher than that achieved in the 11 to 25 category is a clear sign of the changing dynamics within the sector."

He added: "Over the last couple of years, merger activity in the sector and large differences in the growth rates achieved by firms, along with changes in business models and technology, have had a significant impact on what has historically been a relatively stable sector."

Deloitte ascribed the increase in fee income across the top 100 to a 2.6% rise in fee earner headcount and an increase in the average rate per fee earner that firms were able to recover.

Top 100 firms are forecasting a growth of 4% in fee income for the year ahead.