The starting point for a single-sex service is inclusion. Trans people should expect to access and use services in line with their lived experience, and a provider needs a positive, reasoned basis before it departs from that default. The Equality Act 2010 does not require anyone to exclude trans people. What it does is set out a narrow, permissive gateway through which a restriction may — only sometimes, and only when justified — lawfully be applied. This page sets out the default, the gateway, and the proportionality gate any departure has to pass. The worked four-limb test is held back, because that is what the Proportionality Check delivers.
The default is inclusion
Inclusion is not a concession a service makes; it is where the law begins. A trans person using a single-sex service in line with their lived experience is the position a provider starts from and should plan around. Departing from it — restricting access for a trans person — is the exception, not the rule, and it is the provider that has to justify the departure, not the trans person who has to justify their presence. Framing it this way round keeps the decision honest: the question is never “why should we include this person?” but “do we have a proportionate, documented reason to do otherwise?”
The narrow gateway that permits a restriction
The Equality Act’s single-sex and separate-sex exceptions in Schedule 3 allow a service provider to provide a service separately for one sex, or to restrict it to one sex, where doing so is a proportionate means of achieving a legitimate aim. These exceptions are permissive — a power a provider may rely on, never a duty to restrict. Nothing in the Supreme Court’s holding in For Women Scotland requires exclusion either. What FWS settled is that “sex” in the Act means biological sex; it did not settle any individual case, and it did not displace the proportionality requirement that has always governed Schedule 3. The gateway exists, but it is narrow, and walking through it is optional.
A restriction has to be justified, not assumed
Reliance on a single-sex exception is not valid simply because the exception exists. It is valid only where the restriction is a proportionate means of achieving a legitimate aim, assessed on the specific facts of the case in front of you. That is why blanket exclusion is the riskiest option available — it skips the very step the law requires, and it treats the exception as a default when the law treats inclusion that way. The manager decision framework sets out the proportionality reasoning in practice, and the proportionality topic page gives the four-limb idea behind it.
The EHRC Code as the compass
The relevant statutory guidance is the EHRC Code of Practice on services, public functions and associations, in force from 5 August 2026. A statutory code is guidance an organisation must have regard to — not law itself — so what binds is the Equality Act as authoritatively interpreted in FWS, which the Code explains rather than creates. The Code is the compass a service provider should reason with, and the document a tribunal will expect to see you have engaged with when a restriction is challenged.
What this means in practice
The practical task is to start from inclusion, and to recognise that any departure from it requires three things together: a genuine single-sex exception that applies on the facts, a legitimate aim that is real and not assumed, and a proportionality judgement that is reasoned and recorded at the time. Missing any one of the three leaves the decision fragile — and a fragile decision is the worst outcome for everyone it affects. The reading on the 2025 Supreme Court definition of sex separates what that judgment settled from what is still being worked out, which is the frame any decision has to sit in.
Where a proposed restriction carries real exposure, paid support is the right floor. Proportionality Check runs the four-limb test on your facts; Defensibility tests the decision against the scenarios a challenge would bring; Consulting weighs it with you end to end.