For Women Scotland Ltd v The Scottish Ministers [2025] UKSC 16

In brief

The UK Supreme Court unanimously held that references to 'sex' and related terms ('man', 'woman') in the Equality Act 2010 refer to biological sex, not legal sex as modified by a GRC under the Gender Recognition Act 2004. This means that a trans woman with a GRC is legally female for many purposes but remains biologically male for the purposes of EA2010 sex-based provisions, including single-sex exceptions and the Public Sector Equality Duty.

Key provisions

• holding-1 — Sex in EA2010 means biological sex: The Supreme Court held that "sex" in the Equality Act 2010 means biological sex — chromosomal/gonadal sex at birth or conception — not legal sex as modified by a Gender Recognition Certificate.
• holding-2 — A GRC does not change a person's sex for EA2010 purposes: A Gender Recognition Certificate does not change a person's sex for the purposes of the Equality Act 2010. The GRC changes legal sex for most purposes under the GRA 2004, but not the EA2010 definition.
• holding-3 — Single-sex exceptions (Schedule 3, Part 7) operate by reference to biological sex: Single-sex exceptions under Schedule 3, Part 7 of the Equality Act operate by reference to biological sex, not legal or self-identified gender.
• holding-4 — The PSED (s.149) duty regarding sex relates to biological sex: The Public Sector Equality Duty under s.149 regarding sex relates to biological sex. Public authorities must have due regard to the needs of people grouped by biological sex.
• Gender reassignment protection under s.7 is unaffected — remains a protected characteristic: Gender reassignment protection under s.7 is unaffected by the FWS judgment — it remains a protected characteristic in its own right, independent of the biological sex definition.

When relevant

The leading Supreme Court authority on the meaning of sex in the EA2010. Directly relevant whenever: single-sex services or facilities are discussed, Schedule 3 exceptions are invoked, PSED assessments are conducted, organisations change rules post-2025 about women-only spaces or roles, the biological sex vs legal sex distinction matters, GRC holder rights are assessed, sport participation is restricted by sex, membership organisations restrict eligibility, any proportionality assessment involves sex-based or gender-reassignment-based restrictions. Creates a dual-analysis requirement: assess both sex grounds AND gender reassignment proportionality. Applies to ALL sectors: employment, services, sport, education, healthcare, political parties, charities, voluntary associations.