How to Qualify for ISEF: The Path From a Local Science Fair to Regeneron ISEF

Last updated: October 30, 2026

You qualify for ISEF by winning at a science fair affiliated with Society for Science. You cannot apply to ISEF directly. Each affiliated fair (local, regional, state or national) may send a set number of projects to the Regeneron International Science and Engineering Fair, and to compete you must be in grades 9 to 12 or equivalent and not have reached age 20 on or before May 1 before the fair. Your project must also follow the International Rules, which control when your research can start and what must be approved first. This guide explains each step, the rules that disqualify projects, and a timeline for ISEF 2027, which will be held in Los Angeles in May 2027.

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What is ISEF?

The Regeneron International Science and Engineering Fair (ISEF) is run by Society for Science, which calls it the world's largest international pre-college science competition. In 2026, more than 1,700 finalists gathered in Phoenix from May 9 to May 15. They were selected from 365 affiliated fairs in more than 60 countries, regions and territories, and competed for more than $7 million in awards and prizes.

Projects compete in 22 categories, from Animal Sciences and Biochemistry to Behavioral and Social Sciences, Computational Biology and Embedded Systems. (For ideas in the behavioral sciences category, see our psychology research topics for high school students.) About 1,000 professionals serve as judges each year, and all have a PhD or equivalent degree, six years of relevant experience, or both.

Who is eligible for ISEF?

Under the 2026–2027 International Rules, a student must be selected by an ISEF-affiliated fair and must:

be in grades 9–12 or equivalent, and
not have reached age 20 on or before May 1 preceding ISEF.

Other limits:

One project per student. Each student may enter only one project.
Teams of up to three. Team projects may have no more than three members. The team at ISEF must be the same team that competed at the affiliated fair.
One affiliated fair. Students may compete in only one ISEF-affiliated fair, except when moving up from an affiliated regional fair to an affiliated state or national fair.
English. Project boards and abstracts must be in English.

Middle school students cannot compete at ISEF. Their equivalent is the Thermo Fisher Scientific Junior Innovators Challenge: affiliated fairs may nominate the top 10 percent of their 6th, 7th and 8th grade participants. For ideas at that level, see our list of science fair project ideas for middle school.

How to qualify for ISEF, step by step

1. Find your affiliated fair

Search the Society's Find-a-Fair directory for fairs that serve your area. Fairs appear as they complete the annual affiliation process each fall, so check again if yours is not listed yet. Each fair serves a geographic territory, and its website lists its own deadlines, forms and qualifying rounds. Many students start at a school fair that feeds the regional fair.

Society for Science says affiliated fairs exist in all 50 states, the District of Columbia and more than 75 countries, regions and territories. If there is no affiliated fair where you live, the Society suggests asking your school officials to look into affiliation.

2. Read the rules before you collect any data

Most disqualifications come from paperwork and approvals, not from weak science. Before your start date, you need a written Research Plan that covers your rationale, research question or engineering goal, materials, procedures, risk and safety, data analysis plan and bibliography.

If your project involves human participants, vertebrate animals, potentially hazardous biological agents (such as bacteria or mold cultures) or tissue, a local or regional review board must approve it before you start: an Institutional Review Board (IRB) for human participants, or a Scientific Review Committee (SRC) for the other areas. Many human participant and vertebrate animal studies also need a Qualified Scientist to supervise.

The International Rules say the student and the Adult Sponsor decide which forms are required. Every project needs at least the Adult Sponsor checklist, the Student Checklist (1A), the Research Plan, the Approval Form (1B) and the Student Support Disclosure Form (2A). If you have a rules question, ask your fair's SRC, or email the ISEF SRC at SRC@societyforscience.org.

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3. Respect the research window

For ISEF 2027, your project may include no more than 12 months of continuous research and may not include research performed before January 2026. Judges consider only the experiment or data collection performed over 12 continuous months, starting no earlier than January 2026 and ending in May 2027.

Your "start date" is the day you begin collecting data. Background reading and study design happen before it and do not count toward the 12 months.

If your project builds on last year's work, it is a continuation project. You must show that this year's work is a substantial expansion, such as a new variable or a new line of investigation. Repeating the same experiment with a bigger sample does not count.

4. Do original work you can explain

ISEF is for original research and engineering. The rules say demonstrations, literature reviews, "library" research, informational projects and "explanation" models are not appropriate for ISEF.

Working with a mentor is allowed. A project may be part of a larger study run by professional scientists, but you may present only your own part. Your research plan must say which parts you did and which parts the mentor did, and the Student Support Disclosure Form records the help you received.

The rules also limit artificial intelligence. You may use AI as a resource if you cite it, but you may not use generative AI to write your research plan, abstract or poster, or to create citations.

5. Win at your affiliated fair

Fairs choose which projects advance to ISEF. Each fair may send a set number of projects, based on its participation and the size of its high school population. Affiliated fairs all finish by mid-April. According to Society for Science, most U.S. fairs are held from January through March.

After you qualify, you may keep collecting data, but only with the same approved method. The project you present at ISEF must be the same project that won at your fair, with no new variables or procedures.

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A timeline for ISEF 2027

Fall 2026: find your affiliated fair, read its rules and pick a question.
Before your start date: write the Research Plan. Get IRB or SRC approval if your project needs it.
Fall 2026 to winter 2027: collect data. Keep a dated logbook.
4 to 6 weeks before your fair: analyze results, write the abstract and build the board.
January to March 2027: compete at your school, regional or state fair (dates vary by fair).
By mid-April 2027: all affiliated fairs finish.
May 2027: Regeneron ISEF 2027 in Los Angeles.

If you are reading this late in the season, you are not too late for next year. A project for ISEF 2028 can begin data collection under the 2027–2028 rules, which Society for Science posts by June 1.

What do ISEF winners receive?

Society for Science presents more than 600 individual and team awards each year. In each of the 22 categories, first through fourth place awards are $6,000, $2,400, $1,200 and $600. The top winner receives $100,000, and the next two top winners each receive $75,000. Special awards from almost 50 sponsors, worth about $4 million, include scholarships, summer internships, scientific field trips and laboratory equipment.

Is it hard to get into ISEF?

Yes. Every finalist has already won at a fair that sends only a fixed number of projects, and many have moved through a school fair and a regional or state fair first. You do not need a famous lab to compete, but you do need an original question, approvals in place before you start, and enough time to collect real data.

For college applications, ISEF is one of several ways to show research. Our guide to whether research helps college admissions covers how colleges see it.

Want to build a research project over the next 12 weeks? Every application is reviewed individually. Start your application to the STEM Research Program →

Frequently asked questions

How do you get selected for ISEF? You must win at a Society-affiliated science fair. Each affiliated fair sends a set number of projects, so the fair's judges decide who advances.

Can you enter ISEF directly? No. Society for Science calls ISEF a closed event. Students cannot represent themselves; they must be selected by an affiliated fair.

Is qualifying for ISEF a big deal? Yes. ISEF finalists have won through one or more fair levels, and in 2026 the finalists were selected from 365 affiliated fairs in more than 60 countries, regions and territories.

Is ISEF the most prestigious science fair? Society for Science calls ISEF the world's largest international pre-college science competition. It is the top level of the affiliated fair system, so many students treat it as the main goal of a science fair career.

Can middle school students compete in ISEF? No. ISEF is for grades 9–12 or equivalent. Middle school students at affiliated fairs can be nominated for the Thermo Fisher Scientific Junior Innovators Challenge.

Can I do my ISEF project with a mentor? Yes, as long as the work you present is your own. Your research plan must separate your work from your mentor's, and you must complete the Student Support Disclosure Form.

When should I start my ISEF project? For ISEF 2027, data collection may not begin before January 2026, and judges consider only 12 continuous months of research. Most U.S. fairs run January through March, so start collecting data in the fall if you can.

Sources

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