USA Biology Olympiad · 2027 season
The Open Exam is on 3 February 2027, 4 pm ET (online). Student registration closes on 22 November 2026. Dates below are from the organiser, Center for Excellence in Education (CEE), checked on 14 October 2026.
Students cannot sign themselves up: they are registered by a school or an authorised USABO Center — parents cannot register a student themselves. Ask your biology teacher this week. If your school is not taking part, look for an authorised USABO Center before 22 November 2026.
Next: USABO syllabus · past papers · prep plan · past cutoffs
3 February 2027, 4 pm ET (online). It is a 50-minute online multiple-choice exam, no penalty for guessing.
Schools close on 15 November 2026 and student registration closes on 22 November 2026. Students are registered by a school or an authorised USABO Center — parents cannot register a student themselves.
Ask your biology teacher first: a school can still sign up until the school deadline. If your school will not take part, an authorised USABO Center can register you. A parent cannot register a student directly.
Not for the Open Exam: any high-school biology student in grades 9–12; US citizenship is not required for the Open Exam. The Semifinal is for the top 10% of the Open Exam, who must be US citizens or green-card holders.
2 March 2027, 4 pm ET. It is a 120-minute online exam in three parts: multiple choice, multiple true/false, and short answer or essay.
Sources: USABO 2027 calendar (CEE) · About the exams (CEE) · Guidelines and eligibility (CEE)