While civil servants are all paid the same at each grade - women tend to occupy lower down, less well paid jobs
Men dominate the top jobs in government departments and earn on average €8,000 more than women.
Documents released to Newstalk under the Freedom of Information Act (FOI) show 14 of the 16 government departments are led by men.
The next layers of senior management also have a heavy male dominance - while the lower paid roles have a higher percentage of women.
While just two women hold Secretary General positions (earning around €190,000 a year), 76% of those in Clerical Officer roles are women on a median salary of just over €30,000.
That is despite more than 4,500 more women working in government departments than men.
The issue of gender pay has been highlighted this week as a number of RTÉ’s female staff have spoken out about gender inequality.
RTÉ Six One News presenter Sharon Ní Bheolain revealed she gets paid between €60-80,000 less than her co-anchor Bryan Dobson.
While pay rates in the civil service are fixed – meaning men and women are paid the same at each grade regardless of gender – these figures show a glass ceiling remains in terms of women getting promoted to top jobs.
If you take an average of wages from all grades then across government departments women earn about €8,000 less.
The worst offenders are the Department of Finance (€12,766), Department of the Taoiseach (€12,764), Transport, Tourism and Sport (€11,555) and Public Expenditure (€11,125).
Some of these can be misleading however.
The Department of Transport is one of only two departments where women outnumber men across the top four management grades, the other being the Department of Children.
The pay gap in transport arises in the large number of men they hire in technical posts, which includes coastguard officers, aeronautical engineers and other department specific roles. These start on a high pay scale, are almost 100% male, and skew the figures.
The departments with the smallest average wage gap are Social Protection and Health.
In the case of Social Protection this can partly be explained by the fact that the department employs about 3,000 more women than men, largely in Clerical Officer roles.
These would be lower paid roles and would include providing front desk and information services in Intreo offices, assessing benefit applications and other front line services.
The Clerical Officer grade, which is 76% female across all departments and works on a pay scale of €23,500 - €36,500, has been described as the “backbone of the civil service” by sources in several departments.
Departments do have programmes to encourage women to take up leadership roles.
The W-LEAD programme works across departments and provides mentoring for women at the Principal Officer grade.
At the moment, just 38% of workers at that grade are women - raising questions over how difficult it is to get to that point in the first place.
However it is something the Minister for Culture, Heritage and the Gaeltacht Heather Humphreys thinks is improving.
“I actually think it is a good time to be a woman in the civil service because there are more supports than ever to get women into senior roles,” she said.
“For example the civil service renewal plan; it includes a target of 50/50 gender balance in appointments at senior levels.
“So if there are two candidates of equal merit going for a senior position, preference will be given to the female candidate if women are underrepresented in that particular department.”
The ongoing debate over the existence of a gender based ‘glass ceiling’ has led to calls for all government departments to lead by example and publish all their wage data.