The average day rate across all contracts in 2017 is £308. Keep in mind that this looks at all disciplines, all sub-disciplines, all levels of seniority and all contract lengths and all types of clients.
The uncomfortable truth is that the gender pay gap exists for freelancers. Looking at all disciplines on YunoJuno and actual contract information from the last 12 months, we see that men's day rates are on average £15 / day higher than women's.
The difference in rates for men and women vary hugely across different freelancer disciplines.
Women take far higher rates across both Strategy and Client Service roles. Whilst men take notably higher rates across Creative, Design, Film and Motion, Studio and UX.
Rates are largely similar for men and women in Development, Project Management and Social. Although worth noting that almost 85% of all Developer contracts are for men.