In last-minute filings submitted before Wednesday's government deadline, the three companies reported average pay gaps between men and women ranging from 19.9 to 30.9 per cent. Regarding bonuses, the gap was as big as 67.3 per cent.
All of the companies said the number of men in top-earning positions skewed the figures.
The companies were required to publish their gender pay figures in Britain as part of a new regulation compelling all employers with more than 250 staff to do so.
The disparities were starkest at Warner Bros. Entertainment U.K., where men made, on average, 30.9 per cent more than women last year. The company fared even worse on bonuses: although roughly the same proportion of men and women were awarded bonuses, the men received 67.3 per cent more on average.
Warner Bros. said that having more men in high-ranking positions and many long-serving male senior staff members was the root cause of the divide. Of its top-earning quartile of employees, 60 per cent were men. The company said it was addressing the problem of gender inequality through such initiatives as Women of Warner, which offers support and mentoring to its female staff.
Warner Bros. also broke out separate numbers for its 350,000-square-foot Leavesden Studios operation, where the pay gap was 19.8 per cent in favour of men and the bonus gap 54.2 per cent.
Turner Broadcasting System Europe, another Time Warner company, reported a pay gap of 30.2 per cent and bonus gap of 66.1 per cent in the U.K. At CNN, women actually do better than men, with a 2.8 per cent in their favour, reflecting the high proportion of female on-air talent. But the bonus gap at the cable news network was 36.6 per cent to the men.
Turner said that, as an international business, it has non-U.K.-based employees overseeing U.K. operations whose salaries are not included in the figures, as well as well-paid executives overseeing international businesses from London.
"Since Turner is a global business with senior executives based in multiple offices, to focus only on the U.K. does not provide a full picture," the company said in its filing. "We have top female leaders across our business as a whole, with strong female representation in our Europe and international executive teams."
But the company said it was determined "to be even more focused on improving diversity across our workforce and doing more to progress female talent more often, more quickly, and into more senior roles to ensure better female representation across all company lines."
Columbia Pictures Corp., which covers Sony's film and TV distribution activities in the U.K., reported a 23.5 per cent gender pay gap, rising to 45.8 per cent for bonuses. Of its top quartile of earners last year, 55 per cent were male. But the company said that in the 12 months from February 2017, 61 per cent of promotions to senior roles went to women.
The studios' numbers were broadly in line with most other major American media companies with British offices. Disney earlier reported a 22 per cent pay gap and 41.9 per cent bonus gap. NBCUniversal, however, was a notable outlier, reporting a small 3.2 per cent pay gap to men, and a bonus gap of 5.5 per cent in favour of women.
Broadcasters and the large U.K. production and distribution companies have also all been filing. The overwhelming trend was for double-digit pay and bonus gaps. Viacom's Channel 5 was a noteworthy exception, with its female staff receiving 2.85 per cent more than the men. The other instance of female earning equality in a major media workplace was at Endemol Shine, where there was no gap.