Admiral, Coventry Building Society and Santander have now updated their HR procedures to ban transgender visitors and staff from using spaces intended for that biological sex, in line with new guidance issued by the equality watchdog, reports CityAM.

The Equality and Human Rights Commission published its much anticipated code of practice last week, clarifying how to interpret the landmark Supreme Court ruling on the definition of sex last April. Judges ruled that sex under the Equality Act referred to biological sex rather than gender identity.

The guidance stated that service providers should restrict single-sex spaces such as changing rooms and bathrooms to people of that biological sex unless the facilities are self-contained.

It also encouraged firms to provide a “third” or mixed-sex space, on the condition that it doesn’t compromise single-sex provision. It meant that several financial services firms were forced to re-evaluate their diversity, equality and inclusion policies, after several were accused of not conforming with the ruling by charity Sex Matters.

The gender-critical non-profit created a report in May titled Sex-based rights in the city, which listed more than a dozen firms failing to comply with the ruling to enforce women-only facilities. It called out Natwest, Standard Chartered and Prudential. They all declined to comment.

The news outlet reported that the updated EHRC guidance and the report triggered several firms to update their policies. A spokeswoman for Admiral said that following the EHRC’s code, it had “aligned our relevant policies with the legal position”. The firm confirmed it had waited for official guidance before changing its policy, which is understood to have allowed biological males who identified as women to use single-sex spaces.

Coventry Building Society said it had adjusted its policy to “provide a safe and inclusive environment for all colleagues”, adding it is now “complying with the legal guidance and ensuring we offer both single-sex spaces and gender neutral spaces”.

A Santander spokesperson said: “We remain committed to providing an inclusive and respectful workplace for all colleagues, and accessible services for customers across our Work Café network. We are aware of recent guidance from the EHRC and are in the process of reviewing our footprint and policies in light of the recommendations made.”