Weil Gotshal & Manges and Dentons are two of the latest firms to release their gender pay gap statistics for 2018, ahead of tonight's deadline.

Weil's male partners earned 24.8 percent more on average (mean) than their female counterparts in the financial year ending April 2018, down from 27.8 percent in 2017. The median reported figure remained unchanged at 0 percent.

But the gap between male and female non-partners widened from 38.1 percent to 44.1 percent. The median value also increased from 53.3 percent to 60.6 percent.

Despite more women being in receipt of a bonus last year (86 percent versus 80 percent of men), there was a still a 40.7 percent higher rate for males than females. However, this gap was down by 10 percentage points on the previous year.

Weil said that although there are more women overall in its London office – 59.4 percent in total – just over a quarter were in secretarial roles, and just over two thirds of all business services roles were women.

Dentons announced a 56 percent average pay and 47 percent median pay gap in favour of men for all UK employees and partners. Bonuses were also significantly higher for men, with a bonus gap of 70 percent and a median bonus gap of 68 percent.

Once partners are stripped out of the equation, the gap for pay is 24 percent compared with the 2017 figure of 22 percent, but the bonus gap narrows from 52 percent to 41 percent.

The firm said the firm's merger with Scottish firm Maclay Murray & Spens is responsible for the median pay dropping to 20% last year from 34% the year before. Dentons reported a relatively narrow gap among its partners – just 14 percent on average.