UK Supreme Court lowers the causation hurdle for part-time worker discrimination claims
The Tilt · Friday, 11 September 2026
Why it matters
This is a binding change in how comparable part-time and full-time workers are treated: policies applied uniformly on their face can now fall within the regulations when part-time status materially contributes to the disadvantage. It expands the circumstances in which a part-time worker can challenge fixed fees and similar arrangements relative to a comparable full-time worker.
What happened
The UK Supreme Court unanimously ruled that part-time status need only be an effective or significant cause of less favourable treatment under the Part-time Workers (Prevention of Less Favourable Treatment) Regulations 2000; it does not have to be the sole cause. The case concerned a flat weekly fee charged to all Data Cars drivers regardless of how many hours they worked. The ruling rejects the stricter sole-cause approach previously applied under McMenemy and means employers cannot defeat a claim merely by pointing to additional commercial or operational reasons; any disadvantage must still be assessed for objective justification.
Players & places
- United Kingdom
- Supreme Court of the United Kingdom
- Data Cars