National olympiad calendars · NACLO, UKLO, OzCLO dates locked

The three largest English-language national olympiads have locked their Round 1 dates for the 2026 cycle. Confirmed:

• NACLO (US/Canada). Round 1 on Thursday, 22 January 2026. Open round, take from school or online. Round 2 invitation only, Thursday, 12 March 2026.
• UKLO (United Kingdom). Foundation, Intermediate, and Advanced papers all sat 4 February 2026 in school. Top scorers progress to round 2 on 11 March.
• OzCLO (Australia). Round 1 between 17 March and 4 April 2026 (school chooses window). National round 7 May.

If you are a student outside these three jurisdictions, you can still register for IOL via your country’s contact listed at ioling.org. Many countries run smaller selection events and most accept self-nomination plus a portfolio of prior linguistic puzzle work.

The IOL Club Competition page now mirrors these dates with timezone-localised reminders. We will publish each round’s analysis (problem-by-problem) within seven days of paper release.

Filed underNACLO · UKLO · OzCLO · Selection Round

This site is IOL Club, an independent community guide to the International Linguistics Olympiad operated by Hanlin Education. We are not affiliated with the IOL Board or with any national linguistics olympiad. Official rules, host-city announcements, and problem packets are published at ioling.org. Our editors verify every claim against ioling.org and correct confirmed errors within 7 working days.