Week Commencing is a shorthand identifier — written "WC" or "w/c" — for the Monday date that opens a calendar week. It names a 7-day span by its start date.
How it is written
The label takes 3 common forms:
- WC 25 May 2026 — full form with capitalised letters.
- w/c 25/05/2026 — slashed lowercase form, common in UK email.
- WC 25 May — short form when the year is implied by context.
All three identify the same week: Monday 25 May 2026 through Sunday 31 May 2026.
Where it appears
Week Commencing is the dominant week-identifier in UK and Australian business communication. Project plans, shift rosters, meeting agendas, and supplier delivery schedules use the label to avoid ambiguity. UK government departments and Australian state agencies publish operational timetables in WC format.
ISO compatibility
Because Week Commencing always starts on Monday, it aligns with ISO 8601 week boundaries. The same week labelled WC 25 May 2026 is also ISO week date 2026-W22.
If a sender uses Sunday-start US convention, the WC date is shifted by 1 day. Senders should confirm the start day when communicating across regions.