Regeneron ISEF vs Regeneron STS: Which Program Is Right for You?
Same sponsor, different games: ISEF is the international science fair you qualify for through an affiliated fair (grades 9-12, teams allowed); STS is a seniors-only national talent search you apply to directly, judged on an individual research report and its author. Younger students aim at ISEF; seniors with finished individual research can enter both.
Below is a side-by-side comparison of Regeneron International Science and Engineering Fair (ISEF) and Regeneron Science Talent Search (Regeneron STS). A blank row is a fact we do not hold — not a zero, and not a no.
| Regeneron ISEF | Regeneron STS | |
|---|---|---|
| Cost | Varies — see Cost and funding | Varies — see Cost and funding |
| Application deadline | Deadline unconfirmed | November 5, 2026 |
| Grade eligibility | Grades 9–12 | Grade 12 |
| Format | In person | Hybrid |
| Location | Washington, DC, United States | Washington, DC, United States |
| Program dates | Not listed | Not listed |
| Application destination | findafair.societyforscience.org | societyforscience.org |
| Organizer | Society for Science | Society for Science |
Regeneron ISEF vs Regeneron STS: the short answer
Both are run by Society for Science, and they are entered in opposite ways. You cannot enter ISEF directly: you win your way there through a Society-affiliated fair — there are nearly 400 — and more than 1,600 students in grades 9-12 earn the right each year. Team projects are allowed, and the research can cover no more than 12 months of continuous work. STS is a direct application for seniors only, individual research only, judged on a research report of up to 20 pages alongside essays, recommendations and your transcript; about 2,600 enter, 300 are named scholars and 40 finalists go to Washington. The calendar decides a lot: the STS 2027 application closes November 5, 2026 at 8pm ET, while ISEF's affiliated fairs run through the school year and must finish by April 12, 2027, ahead of ISEF 2027 in Los Angeles on May 8-14. A senior with finished individual research can do both.
Program details
These are the current details stored for each program. A blank cell means the catalog does not hold that detail.
| Regeneron ISEF | Regeneron STS | |
|---|---|---|
| How you get in | Through a Society-affiliated fair, the first step to ISEF; there are nearly 400 worldwide. | A direct online application; hard copies are not accepted. |
| Who can apply | Grades 9-12, by winning at a Regeneron ISEF affiliated fair. | Students in their last year of secondary school living in the US and its territories, regardless of citizenship. |
| Team projects | Allowed: team members split an award equally. | Not allowed: only independent, individual research is eligible. |
| Which research counts | No more than 12 months of continuous research, none done more than 18 months before the ISEF you compete in. | Research from any year of high school. |
| What you submit | Your project at your affiliated fair first; each fair may send a set number of projects to ISEF, in 22 categories. | Essays, project questions, an original scientific paper of up to 20 pages, recommendations, transcripts and optional test scores. |
| How many advance | More than 1,600 ninth through twelfth graders earn a place at ISEF each year. | 300 scholars and 40 finalists, chosen from more than 2,600 applicants in 2026. |
| Awards | $6,000, $2,400, $1,200 and $600 by place in each of 22 categories; the top winner receives $100,000 and the next two $75,000 each. | $2,000 to each of 300 scholars plus $2,000 to their schools; all 40 finalists get an all-expenses-paid week in Washington and compete for the top 10 awards, the highest $250,000. |
| Cost to enter | Not stated. The ISEF FAQ explains how affiliated fairs send projects on and names no student entry fee. | Not stated. The STS FAQ describes the application in detail and names no entry fee. |
| Deadline, most recent published cycle | Your affiliated fair's own date; every affiliated fair must be held by April 12, 2027. | November 5, 2026 at 8pm ET, for the next competition. |
Inside Regeneron ISEF
A ladder. You start at a school, local or regional fair, and a Society-affiliated fair — local, regional, state or national — sends a set number of its projects on; those fairs all finish by mid-April. At ISEF itself, in May, each project is judged at least four times by professionals with a Ph.D. or years of experience, across 22 categories, with special awards from sponsors on top of the grand awards.
Inside Regeneron STS
One application. You write up individual research you have already done — in a lab, at school or at home — as a report of up to 20 pages, and add essays, recommendations and a transcript. At least three PhD scientists, mathematicians or engineers review each entry. In January 300 scholars are named, then 40 finalists, who spend a week in Washington in March for project and panel judging.
Choose Regeneron ISEF if…
- You are in 9th, 10th or 11th grade. ISEF is open through affiliated fairs in grades 9-12; STS takes only students in their last year.
- Your project is a team project. ISEF allows teams; STS accepts only independent, individual research.
Choose Regeneron STS if…
- You are a senior with finished individual research. STS takes research from any year of high school and is a direct application, due November 5, 2026.
- Your area has no affiliated fair you can reach. STS does not go through a fair; ISEF can only be reached through one.
Applying next cycle: what to do now
| Regeneron ISEF | Regeneron STS | |
|---|---|---|
| Next program dates | Regeneron ISEF 2027: May 8-14, 2027, in Los Angeles. | Top 300 scholars on January 7, 2027; top 40 finalists on January 21, 2027; finals week March 11-17, 2027. |
Applying to Regeneron ISEF
- Start with your local fair: every affiliated fair has a Scientific Review Committee to answer rules questions before you experiment.
Applying to Regeneron STS
- Generative AI may not write application answers, the research report or citations.
- Participation in a paid research program must be disclosed by you and your mentor.
What this comparison cannot tell you
- ISEF's costs depend on your affiliated fair, and neither program's pages we read name an entry fee.
- STS's counts are its 2026 cycle's; ISEF's are its own round numbers for a typical year.
- The two rulebooks differ in significant ways, so a project built for one is not automatically eligible for the other.
Regeneron International Science and Engineering Fair (ISEF)
The world's largest international pre-college science competition, by its organizer's description.
Regeneron Science Talent Search (Regeneron STS)
Over 2,600 seniors a year complete independent science, math or engineering research and enter it.
Frequently asked questions
Which is cheaper, Regeneron ISEF or Regeneron STS?
Regeneron ISEF: Varies — see Cost and funding. Regeneron STS: Varies — see Cost and funding. Confirm each figure on the program's official page before budgeting.
Can I apply to both Regeneron ISEF and Regeneron STS?
The application destinations are evaluated independently. Regeneron ISEF: findafair.societyforscience.org. Regeneron STS: societyforscience.org. Review each provider's current instructions before assuming either application is open or compatible with the other.
Which is better for college applications, Regeneron ISEF or Regeneron STS?
We do not rank enrichment programs by admissions value. Use the comparison to assess whether each program's documented constraints fit your situation, and check the details that decide it for you on each program's official page.
What grades can apply to Regeneron ISEF and Regeneron STS?
Regeneron ISEF: Grades 9–12. Regeneron STS: Grade 12. Eligibility can change between cycles, so confirm it on each program's official page before applying.
Related comparisons
Regeneron ISEF appears in 1 of 56 comparison pages. Regeneron STS appears in 2 of 56 comparison pages.
How we count
Our comparison list has 56 pairs covering 91 catalog programs. Those numbers count this list only. They are not a ranking or the size of the full catalog.
We don't rank programs or name one of them the best.
When we don't list a cost, it is unknown, not free. Check the official page.
Catalog-wide numbers, and what each was counted out of, are on Statistics.