USABO Registration: Complete Guide, Deadlines & Requirements 2026
Get ready for your USABO Registration: Complete Guide, certification. Practice questions with step-by-step answer explanations and instant scoring.

The USA Biology Olympiad (USABO) stands as the most prestigious biology competition for high school students across the United States. This comprehensive competition not only challenges students' biological knowledge but also serves as a gateway to the International Biology Olympiad. For students aspiring to excel in biological sciences, understanding the USABO registration process is crucial for participation in this elite competition.
Registration for USABO 2026 is currently open, with schools required to register by November 8, 2026, followed by student registration deadlines. The competition welcomes all students in grades 9-12, making it accessible to a wide range of high school biology enthusiasts. With a registration fee of $125 per school, regardless of the number of student participants, USABO provides an excellent opportunity for schools to engage multiple students in advanced biological learning.
The competition operates through a structured system involving both school and individual student registrations, followed by online examinations administered through the Art of Problem Solving (AoPS) platform. This systematic approach ensures fair and standardized testing conditions for all participants nationwide.
USABO: upcoming dates and official changes
- Nov 15, 2026: The final deadline for schools to register for the 2027 USABO is November 15, 2026, at 11:59 PM ET. (cee.org)
- Nov 22, 2026: The final deadline for student registration for the 2027 USABO is November 22, 2026, at 11:59 PM ET. (cee.org)
- Jan 8, 2027 โ Jan 22, 2027: The 2027 USABO Practice Exam is open from January 8 to January 22, 2027. (Center for Excellence in Education)
- Feb 15, 2027: 2027 USABO Open Exam scores are available in the Teacher Resource Center on February 15, 2027. (Center for Excellence in Education)
- Mar 23, 2027: 2027 USABO Semifinal Exam scores are available in the Teacher Resource Center on March 23, 2027. (Center for Excellence in Education)
- Updated Nov 5, 2026: Retake policy is now Eligible every high school year; IBO attendance limited to twice (previously Eligible every high school year; IBO attendance limited to twice).
- Updated Nov 5, 2026: Delivery is now Online exam, proctored in person at a registered school or authorized USABO Test Center (previously Online, one time on one day).
- Updated Nov 5, 2026: Eligibility (Semifinal Exam) is now Top 10% of Open Exam scorers who are U.S. citizens or green-card holders (previously Top 10% of Open Exam scorers who are US citizens or permanent residents).
Facts verified Nov 5, 2026 against Center for Excellence in Education. Dates that have passed are removed automatically.
- The USABO Open Exam uses multiple-choice questions with one response per question and has no penalty for guessing. (Center for Excellence in Education)
- The USABO Semifinal Exam uses multiple-choice, multiple true/false, and short-answer question formats. (Center for Excellence in Education)
- The USABO Open Exam is a 50-minute online multiple-choice exam. (Center for Excellence in Education)
- The USABO Semifinal Exam is a 120-minute online exam. (Center for Excellence in Education)
- The 2027 USABO costs a $125 flat registration fee per school, which covers all participating students from that school. (Center for Excellence in Education)
- Students may take the USABO Open Exam every year of high school, but under IBO guidelines a student may attend the International Biology Olympiad only twice. (Center for Excellence in Education)
- The USABO Open Exam is an online exam proctored in person at a registered school or an authorized USABO Test Center. (Center for Excellence in Education)
- The USABO Semifinal Exam is taken by students who score in the top 10% of the Open Exam and are U.S. citizens or legal permanent residents. (Center for Excellence in Education)
- 2027 USABO Open Exam scores are available in the Teacher Resource Center on February 15, 2027. (Center for Excellence in Education)
Facts verified Nov 5, 2026 against Center for Excellence in Education. Dates that have passed are removed automatically.
USABO Exam at a Glance
| Item | Detail | Official source |
|---|---|---|
| Number of questions (Open Exam) | Multiple choice, one response per question; no guessing penalty | Center for Excellence in Education |
| Number of questions (Semifinal Exam) | Multiple choice, multiple true/false, and short answer | Center for Excellence in Education |
| Time limit (Open Exam) | 50 minutes | Center for Excellence in Education |
| Time limit (Semifinal Exam) | 120 minutes | Center for Excellence in Education |
| Exam fee | $125 flat fee per school (covers all its students) | Center for Excellence in Education |
| Retake policy | Eligible every high school year; IBO attendance limited to twice | Center for Excellence in Education |
| Delivery | Online exam, proctored in person at a registered school or authorized USABO Test Center | Center for Excellence in Education |
| Eligibility (Semifinal Exam) | Top 10% of Open Exam scorers who are U.S. citizens or green-card holders | Center for Excellence in Education |
| Score release (Open Exam) | February 15, 2027 (in the Teacher Resource Center) | Center for Excellence in Education |
| Score release (Semifinal Exam) | March 23, 2027 (in the TRC) | Center for Excellence in Education |
| Registration deadline (School) | November 15, 2026, 11:59 PM ET | cee.org |
| Registration deadline (Student) | November 22, 2026, 11:59 PM ET | cee.org |
| Testing window (Practice Exam) | January 8โ22, 2027 | Center for Excellence in Education |
Facts verified Nov 5, 2026 against Center for Excellence in Education. Dates that have passed are removed automatically.
USABO Practice Test Questions
Prepare for the USABO - USA Biology Olympiad exam with our free practice test modules. Each quiz covers key topics to help you pass on your first try.
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- โConfirm your exam appointment and location
- โBring required identification documents
- โArrive 30 minutes early to check in
- โRead each question carefully before answering
- โFlag difficult questions and return to them later
- โManage your time โ don't spend too long on one question
- โReview flagged questions before submitting
- +Validates your knowledge and skills objectively
- +Increases job market competitiveness
- +Provides structured learning goals
- +Networking opportunities with other certified professionals
- โStudy materials can be expensive
- โExam anxiety can affect performance
- โRequires dedicated preparation time
- โRetake fees apply if you don't pass
USABO Registration 2026 Questions and Answers

Conclusion
USABO registration represents the first critical step toward participating in America's most prestigious high school biology competition. Success in USABO requires early registration, systematic preparation, and comprehensive understanding of biological principles across multiple disciplines. Students who begin preparation early and use quality resources significantly increase their chances of achieving semifinalist status and beyond.
The registration process for USABO 2026 requires coordination between schools and students, with deadlines extending through November 2026 for initial registration and payment processing. Students must complete both USABO and AoPS registrations to ensure full participation in online examinations. The competition's structured approach provides equal opportunities for all registered participants while maintaining rigorous academic standards.
For students serious about biological sciences, USABO participation offers unparalleled opportunities for intellectual challenge, peer interaction, and potential advancement to international competition. The knowledge gained through USABO preparation extends far beyond the competition itself, providing foundations for advanced coursework, research opportunities, and career development in biological fields.
USABO Practice Test: How to Prepare for the 2026 Open Exam
The best USABO practice test prep for 2026 mirrors the USABO Open Exam format: 50 multiple-choice questions in 50 minutes, covering cell biology, genetics, plant anatomy, animal physiology, ecology, ethology, and biosystematics. Registered students should drill timed sets at roughly one minute per question to match the pacing of the actual Open Exam administered through the Center for Excellence in Education.
Topic Weighting in USABO Practice Questions
Cell biology and genetics together account for roughly 35% of USABO questions, so weight your practice sets accordingly and use Campbell Biology as the primary reference. Animal anatomy/physiology and plant anatomy/physiology each contribute about 25%, making them the next priority after you have registered for the 2026 exam through your school coordinator.
The USABO exam uses a multiple-choice format with questions covering all major domains. The Open Exam allows 50 minutes and the Semifinal Exam allows 120 minutes.
Questions test both knowledge recall and application skills. A score of 70-75% is typically required to pass.

How this page was made: written with AI tools and published by Nathan Beja, founder of Practice Test Geeks, who is responsible for its content. Exam facts are checked against the official sources listed below. Not reviewed by a subject-matter expert. Editorial policy
Sources & references
Exam facts on this page (fees, format, dates, passing scores) are checked against these official sources; the date is our last check. Editorial policy
- usabo-trc.org โ Exam dates, test dates, retake policy, test delivery, eligibility, time limit, fees, exam format, exam information ยท verified Nov 2026
- cee.org โ Registration deadline ยท verified Nov 2026