Rules, eligibility & the four-tier pathway
The U.S. National Chemistry Olympiad is a single competition run in four stages, from a Local Exam every March to the International Chemistry Olympiad each July. This page sets out who can compete, how to enter, how students advance from tier to tier, and the key 2026 dates.
Who can compete, and how to enter
The USNCO is open to U.S. high-school students, and the entry point is genuinely open: any eligible student can sit the Local Chemistry Olympiad each March. No invitation, ranking, or prior result is required to begin. The field narrows on the strength of exam scores, not on who you know.
Entry runs through the American Chemical Society’s network of Local Sections. You register for the Local Exam through your ACS Local Section Coordinator, who organizes the exam in your region, supervises it, and nominates the top scorers for the National Exam. If you are unsure which Local Section covers your school, your chemistry teacher or the ACS Local Section directory can point you to the right coordinator.
One requirement applies higher up the pathway: students selected for the U.S. international team must be U.S. citizens or permanent residents and able to show a U.S. passport or green card. This is an International Chemistry Olympiad rule for national-team membership, not a barrier to entering the Local and National exams.
- U.S. high-school students of any grade level
- No invitation needed to start the Local Exam
- Register through your ACS Local Section Coordinator
- Advancement is decided by exam scores alone
- U.S. citizen or permanent resident required for the international team (passport or green card)
- One nationally administered set of exams, sat under supervision
The four tiers in detail
Each tier is harder than the last, and each one selects the students who continue. Together they form a single ladder from the local classroom to the international stage.
Local Chemistry Olympiad
The open entry point. Students register through their ACS Local Section and sit the Local Exam in their region each March. Coordinators score the papers and nominate their top performers to advance to the National Exam.
National Chemistry Olympiad
A three-part national exam taken by more than 1,000 nominated students each April, usually hosted at universities and colleges. It combines multiple-choice, written free-response, and a laboratory practical to identify the top 20.
Study Camp
The 20 highest scorers spend two weeks at a residential camp in June, training intensively in advanced theory and laboratory work. From this group, four students are chosen to represent the United States as Team USA.
International Chemistry Olympiad
The four U.S. students compete internationally each July, supported by mentors who translate the exam, inspect the laboratories, and arbitrate the scoring. The IChO is the summit of the USNCO pathway.
How students advance, tier to tier
Advancement is earned at every stage, and the rule is the same throughout: results decide who continues. At the local level, each ACS Local Section nominates its strongest scorers for the National Exam, so the size of the national field reflects performance across the country rather than a fixed quota per school.
The National Exam is where the field narrows sharply. Its three parts together rank the nominated students, and the 20 highest scorers nationwide earn places at the June Study Camp. At camp, two weeks of theory and laboratory training culminate in the selection of four students for Team USA, who go on to the International Chemistry Olympiad in July.
Recognition does not begin only at the top. The National Exam carries national honors that mark out strong performances well beyond the final four, giving many students a credential that reflects how far they advanced.
The 20 highest scorers on the National Exam, who advance to the June Study Camp and compete for the four Team USA places.
Awarded to students whose National Exam results place them among the strongest performers in the country.
Awarded to students who perform strongly on the National Exam, recognizing a result that stands out nationwide.
Key dates for the 2026 season
Registration for the 2026 season opened on 6 October 2025 through ACS Local Section Coordinators. From there the season runs on a fixed calendar, from the Local Exam window in late winter to the International Chemistry Olympiad in July.
The single most important step is registering with your Local Section in good time, so you are entered for the Local Exam window. Everything that follows depends on that first exam.
Register through your ACS Local Section Coordinator.
Sat in your region during the local exam window.
Three-part exam for nominated students.
Two-week residential camp for the top 20.
Team USA competes on the international stage.
Competition FAQ
The USNCO is open to U.S. high-school students of any grade. Any eligible student can sit the Local Exam each March, with no invitation or prior result required. Students selected for the international team must additionally be U.S. citizens or permanent residents.
You register for the Local Exam through your ACS Local Section Coordinator, who organizes and supervises the exam in your region. Your chemistry teacher or the ACS Local Section directory can help you find the right coordinator for your school.
Results decide every step. Local Section coordinators nominate their top scorers for the National Exam, the National Exam selects the top 20 for the June Study Camp, and four of those students are chosen at camp to represent the United States as Team USA.
The National Exam carries three national honors: Top 20, High Honors, and Honors. Higher up the pathway, the four members of Team USA compete for medals at the International Chemistry Olympiad each July.
The USNCO is designed for U.S. high-school students, and membership of the international team requires U.S. citizenship or permanent residency with a passport or green card. International students should look to their own country’s national chemistry olympiad as their pathway to the IChO.
For the 2026 season, registration opened on 6 October 2025 through ACS Local Section Coordinators. Registration windows are set each season, so the best approach is to contact your Local Section early to confirm dates and reserve your place for the Local Exam.
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