While the biggest winners are Western Australian men, who have continued to earn more than those employed in the capital with an average of $1826.4 a week before tax ($94,973 a year), their lead has narrowed.

The Australian Bureau of Statistics data issued on Thursday revealed men in WA are earning an average of $31.30 a week more than their ACT counterparts, who have taken home $1795.1 ($93,345 a year).

Canberra's female workers are still the highest paid women in the country at $1587.7 a week, or $82,560 a year.

This figure is almost 15 per cent higher than Australia's second-biggest female earners in Western Australia who earn an average of $1358.3 a week ($70,632 a year).

Canberrans employed full-time have continued to earn well above the national average of $1477.00 a week, or $76,804 annually.

Across Australia men have continued to earn substantially more than women on $1587.4 a week ($82,545) compared to the average weekly female wage of $1289.30 ($67,044).

The Australian Council of Trade Union president Ged Kearney slammed the 18.8 per cent difference, calling for strengthened workplace gender equality reporting.

In the ACT, the gender pay gap is 11.6 per cent.

"The government has delayed its decision about what details businesses will be required to report for women in non-management roles, which represents the majority of women in the workforce," she said.

"Without meaningful data employers cannot identify where gender pay gaps exist and take action to address discrimination and barriers many women face. The Workplace Gender Equality Agency needs to be strengthened – not watered down."