The recruiters say that the share of female board members has risen by more than 50 per cent in just three years, from 19 per cent to 31 per cent.
According to the report, British banks have outpaced many of their global competitors, including firms in the United States and China, which saw a decrease in the number of women on their boards over the same time period.
While European banks have the highest proportion of board members who are women (35 per cent), the growth in the number of women on continental European banking boards has been slower than the growth seen on UK banking boards, Astbury Marsden said.
The recruitment firm pointed to the targets set by Lord Davies to explain the rapid growth in female executives in the UK.
Davies had recommended that FTSE 100 companies make sure that at least one-quarter of their board members were female by 2015.
Global investment banks lag behind commercial and diversified banks in terms of the number of women at the most senior level – just 16 per cent of board members of investment banks are women.
“The ‘Women on Boards’ initiative has encouraged all FTSE100 companies to have a greater representation of women on their boards, but with all the public and political focus there has been on the banking sector, it has been under particular pressure to diversify,” said Astbury Marsden managing director Adam Jackson.
“For a long time banks were seen as an ‘old boys club’, but this mentality is changing.”