Large wealth managers are among those who have the most work to do in order to close the gender pay gap, with a handful still having a mean difference in pay of around 50 percent.

Brown Shipley, a Quintet Private Bank, posted one of the highest mean differences in pay, at 51.7 percent. 

Furthermore, less than a fifth (19.1 percent) of its upper pay quartile was made up of women. Conversely, women accounted for 69.1 percent of the firm’s lowest pay...