Yes. You must give men and women equal treatment in the terms and conditions of their employment contract if they are employed on:
- 'like work': work that is the same or broadly similar
- work rated as equivalent under a job evaluation study (See: Recruitment and management), which must be a proper analysis of the demands made on employees in their jobs under various headings such as effort, skill and decision making and impartial in its application to men and women, or
- work found to be of equal value
A woman is employed on 'like work' with a man if her work is of the same or a broadly similar nature. It is up to you as her employer to show that there is a genuine reason for any difference not based on the sex of an individual.
You should try to resolve the problem informally, but be aware that individuals may complain to an employment tribunal under the Equal Pay Act 1970 while still working for you or up to six months after leaving the employment to which their claim relates. Normally, they may claim arrears of remuneration (which includes sick pay, holiday pay, bonuses, overtime etc as well as 'pay') for a period of up to six years (five years in Scotland) before the date of their tribunal application.