The value of pro bono work provided by private practice solicitors has reached £475m, according to Law Society research.

The figure represents a 19% annual increase and is equivalent to an estimated 2% of the total gross income of private practice.

The sample of 1,200 solicitors interviewed in the spring of 2010 showed that half of private practice solicitors had undertaken pro bono work in the previous 12 months, a slight increase on 48% in 2008/09.

The research showed that in private practice, almost two-thirds of equity partners (64%), 52% of sole practitioners and 46% of salaried partners had worked pro bono in the previous 12 months. Some 45% of assistant and associate solicitors had done so.

Solicitors working in private practice were around three times more likely to have undertaken pro bono work than those working in commerce and industry (15%) or in government (17%).

The overall number of hours of pro bono work reported remained at an average of 45 hours per year, per solicitor, the same as in the previous year.

However, the latest research revealed differences in relation to the size of the firm in which volunteer solicitors worked. In 2010, solicitors working in firms with five to 10 partners reported the highest average pro bono hours (71) followed by sole practitioners (68). In 2009, solicitors working in two to four partner, and 11 to 25 partner firms had reported the highest number of pro bono hours.

In both years, those working in the largest firms, with 26 or more partners, spent the least time on pro bono clients (31 hours in 2010).

Overall, 59% of practising certificate holders reported that they have done pro bono work at some point during their legal career.