A fifth of London tech companies still have no women at board level, a new study has revealed, and women hold less than a quarter of senior management roles in almost half of the capital's organisations.

Of the 433 companies surveyed by private sector tech network Tech London Advocates, 18 per cent reported having no females on their board and only 23 per cent of companies have senior management teams that match the gender diversity of London's population.

Russ Shaw, founder of Tech London Advocates, said: "Technology's gender problem has not gone away. Female CEOs have been instrumental to the rise of London's tech sector, creating some of the city's most exciting businesses, but the lack of wider representation for women at senior levels is shameful.

"London Technology Week is an opportunity to celebrate the opportunities technology companies hold for all Londoners, cutting across age, gender and background. Simply put, failing to harness the creative potential of those currently under-represented in the industry makes bad business sense."

Despite low figures, 60 per cent of London's tech community taking part in the survey said their company had actively tried to increase diversity at recruitment level.

"Failing to engage women in technology careers undermines the open, diverse outlook of the digital industry," said Sarah Luxford, director at Nexec Leaders and TLA Women in Tech lead. "With such a requirement for tech professionals, harnessing the potential of 50 per cent of the population is the solution to long-term growth."