Your next action
Invited to the 48th OBM? Check your name in the organiser’s list, confirm participation and select an exam centre through the official notice. If you are not invited, first identify a recognised qualifying route with your teacher.
- Season / status
- OBM 2026; confirmation is for invited students, not open beginner registration.
- Confirmation deadline
- 2 October 2026 at 23:59. The notice does not label the deadline time zone; confirm with OBM and act early.
- Exam dates
- 8 October: all levels. 9 October: levels 2, 3 and university. Exam sessions: 14:00–18:30 Brasília time.
- Who acts
- The invited student confirms and chooses a centre. OBM says the lists may be updated.
- Fee / level
- A fee is not stated in this confirmation notice. School levels and the university competition are separate.
OBM invitation and confirmation notice, 20 September 2026 · Deadline checklist and exam arrangements
Entry information checked 24 September 2026. Dates apply only to the named season. Your school or host may need an earlier decision.
Organisers
Olimpíada Brasileira de Matemática (OBM) and the national Olympiad commission of Sociedade Brasileira de Matemática.
How to enter
First qualify through an accepted feeder route. Current OBM entry routes include specified OBMEP awards, earlier OBM awards, Torneio Meninas na Matemática, Jacob Palis Júnior and supported regional Olympiads. OBM is not simply open registration for every school student. OBM participation rules
International route
Eligible award recipients → IMO selection tests → team selection. The 2026 policy includes direct qualifying TM² award categories as well as OBM categories; OBM scores and three or four selection tests contribute under the published formula. 2026 international-selection regulations
For cross-border schooling, home education or national-team eligibility, read the shared eligibility guide and obtain the national organiser’s ruling.
Past papers and solutions
OBM organises its archive by year, level and phase. For school preparation, select the appropriate school level; the university-level paper is a separate contest. A gabarito may be an answer key, so check whether the file also gives complete reasoning.
Previous results
OBM official result announcements covers the domestic programme. For international appearances, medals and contestant records, use Brazil in the official IMO archive. A national-round award and an IMO medal describe different achievements.
Find papers from other countries · Understand result tables and medal cut-offs
Suggest a correction or an updated official notice
If your school does not take part
Ask OBM which recognised qualifying route is available for your school level and location. A previous OBM medal or another qualifying result may matter; do not assume open entry to a selection test.
Use the short organiser-enquiry checklist · Find practice for this country