The 39-page State of the Profession report, compiled by Survation on behalf of the CIPR, surveyed 1,578 public relations professionals between October and December last year.
It found men earned an average salary of £58,115, which is in comparison to women who earn £45,779.
This is despite women accounting for 61 per cent of the jobs in the UK PR industry. Fifty-seven per cent of these identify as head of comms and 53 per cent identify as an owner, MD or partner.
The survey also reveals the mean gender pay gap across the UK PR industry is just over £12,300, but the CIPR said the "true" gender pay gap is £5,784, following regression analysis that removed external factors such as education, sector of practice, graduate status, time spent in the industry, seniority, and gender.
Survation then scrutinised these criteria to determine whether any had a "meaningful impact" on pay, the CIPR said.
"The company found that there are three significant variables that impact PR pay – these are seniority, time spent in the industry and gender. The first two you’d expect to influence salary but not gender, which has the third largest influence of any variable on pay for PR professionals," a CIPR spokesman said.
A survey last year suggested that the gender pay gap in global PR is £12,600 - which is higher than a previous UK-specific figure of around £10,000.
The survey reveals the average salary of a PR professional in the UK - both those working in-house and agency-side - increased across the board, rising from £45,588 in 2016 to £50,447 this year.
However, the average salary in London (£66,102) is almost £30,000 higher than in Northern Ireland, where PR professionals receive an average salary of £36,537.
Those in Wales and Scotland fare slightly better, receiving an average salary of £37,181 and £43,099, respectively.
Elsewhere in England, PRs in the north can expect £43,297, while their counterparts in the Midlands and east England can expect £43,790.
In the south of England, including the Channel Islands, PR professionals earn £44,899 on average, which is the highest wage outside London in the UK.
More than a quarter of respondents said they earned between £60,000 and over £100,000, while only five per cent said they earned less than £20,000.
In a similar survey conducted by the PRCA last year, London also boasted the highest average pay, at nearly £49,000, while average pay in the south east was £45,000.
As with the CIPR study, the PRCA found pay in Northern Ireland to be the lowest in the UK, at £35,000, while those in Wales could have expected £36,000.
When the PRCA survey was published, its groups manager Souha Khairallah said the examples of pay disparity were "not surprising". "But we should continue to monitor to ensure that we do not end up in a situation where we have huge UK-wide inconsistencies," Khairallah said.
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