More than 500 organisations across the country have now published figures showing the difference in average pay and bonuses for their male and female workers.
Among them are a school in Sheffield, where the mean hourly rate for women is 12.8 per cent less than for men, and Doncaster Council, where men earn on average 15.7 per cent more than women.
In total, seven organisations in South Yorkshire have so far released figures, including four in Sheffield, two in Doncaster and one in Barnsley.
A gender pay gap does not mean workers of one sex are paid more for doing the same job, which is illegal under equal pay legislation. It usually indicates there are more men, or in some cases more women, occupying senior positions and therefore taking home bigger pay packets.
The Government has made it mandatory for all organisations with 250 or more workers to report annually on their gender pay gap, in an attempt to narrow the divide, and those bodies must publish their first set of data by April.
The organisations in South Yorkshire which have published figures to date, and the difference in mean hourly pay between male and female employees there, are:
Linbrooke Services Ltd, Churchill Way, Chapeltown, Sheffield: + 28 per cent
MJ Gleeson PLC, Sheffield Business Park, Tinsley, Sheffield: + 8.3 per cent
TWINKL LTD, Ecclesall Road, Sheffield: + 2 per cent
Wales High School, Kiveton Park, Sheffield: + 12.8 per cent
Doncaster Children's Services Trust: + 13.1 per cent
Doncaster Council: + 15.7 per cent
Naylor Industries PLC, Cawthorne, Barnsley: - 15 per cent
Nationally, easyJet has revealed its female employees earn on average 52 per cent less than men.
Just six per cent of the airline's pilots, earning an average salary of £92,400, are female, yet women account for 69 per cent of its cabin crew, earning £24,800 on average.
The firm has said it is actively seeking to recruit more female pilots, having set itself a target of 20 per cent of new entrant pilots being women by 2020.
The BBC reported its mean hourly rate for women was 10.7 per cent lower than for men, while the difference was 30 per cent at the Co-operative Bank.
However, there were some firms bucking the trend of women earning significantly less.
The British Museum, for example, reported no gender pay gap and the UK Armed Forces said the gap there was just 0.9 per cent in favour of men, while Cambridgeshire Police revealed its female employees had a mean hourly pay of 13 per cent more than men working there.
* In the list of South Yorkshire firms above, a positive figure indicates men there earn more than women, while a negative one indicates the reverse.