Competition · Math · Canadian Mathematical Society

Canadian Mathematical Olympiad and Canadian Junior Mathematical Olympiad

Canada's top invitation-only math olympiad. Students qualify mainly through a high COMC score. Usually written in March.

Last checked October 5, 2026 against the official page

What do I need to do?

Write the COMC on October 29: that is the main way in

Who acts
Student
Preparation
Significant preparation Proof-based olympiad problems; months of practice
Eligible grades
Grades 8–12
Format
3-hour proctored written paper, by invitation.
Cost
No separate entry. Students qualify through the COMC.
Official site
cms.math.ca

Key dates

  • ConfirmedCOMC (qualifying contest)Thu, October 29, 2026Remind me
  • ExpectedCMO and CJMOExpected March 2027 (2026: March 12)

Get a reminder before every deadline for your child →

Confirmed official date · Expected based on last year · Not announced yet

What it is

The CMO and the CJMO (for Grade 10 and below) are 3-hour proof-based papers. They are by invitation only.

Most invitations go to top students from the COMC, about 100–120 students a year. The old CMO qualifying repêchage (CMOQR) has been discontinued.

Students must be in secondary school full-time, under 20 on June 30, and Canadian citizens or meet the International Mathematical Olympiad residency rules.

A good fit if: Students who scored very well on the COMC and enjoy proof-based problems.

How to register

  1. There is no direct registration. Write the COMC. Top scorers are invited.
  2. The COMC is on October 29, 2026.

How to prepare

  • Do well on the COMC first. That is the main way in.
  • Practise writing full proofs. UBC/PIMS Math Circles can help.

For grade-by-grade options see Grade 8, Grade 9, Grade 10, Grade 11, Grade 12.

Common questions

Can my child sign up for the CMO directly?

No. It's by invitation. Most invitations go to top COMC students.

What's the CJMO?

The junior version of the olympiad, for students in Grade 10 or below.

Sources

Last checked October 5, 2026. Dates can change, so always confirm with the organizer.