Students invited to Brazil’s 48th Olimpíada Brasileira de Matemática (OBM) need to confirm their participation by Friday, 2 October 2026. The organiser’s notice dated 20 September asks listed students to complete the data-collection form and choose an examination centre.
Who needs to act?
This deadline concerns invited participants. OBM’s participation rules use qualifying results from recognised competitions, including specified OBMEP, previous OBM, Torneio Meninas na Matemática, Jacob Palis Júnior and supported regional Olympiad awards. The university level has separate entry routes. Meeting a qualifying route remains subject to the competition regulations.
If you are beginning Olympiad preparation, use our Brazil selection guide to identify an appropriate first step. This confirmation deadline is not a general sign-up opportunity for every student.
Check your invitation and examination centre
The notice says the invitation list will still be updated with students selected through supported regional Olympiads. Examination-centre information is also being updated, and the confirmation form allows editing.
Check your invitation, follow the organiser’s confirmation instructions and keep a record of your submission. If you cannot locate your invitation or form, ask OBM before the deadline rather than treating this article as confirmation of a place.
Deadline time: the notice specifies 23:59 on 2 October but does not explicitly label the time zone for that cutoff. Confirm the deadline’s time basis with OBM if this affects your submission; the examination times below are explicitly in Brasília time.
When are the examinations?
The official 2026 calendar lists:
- 8 October: first day for levels 1, 2, 3 and university.
- 9 October: second day for levels 2, 3 and university.
The invitation notice gives each examination session as 14:00–18:30, Brasília time. Check the current centre instructions before arranging travel.
For practice, visit OBM’s official papers and answer archive and choose your level. The organiser’s current notice and regulations govern participation.