NIH R21 Grants — Exploratory/Developmental Grant
Novel, high-risk/high-reward exploratory research
Funding
Up to $275,000 direct costs over 2 years (combined)
Duration
Up to 2 years
Eligibility
Any qualified investigator; preliminary data not required
Activity code
R21
What is the NIH R21 grant?
The R21 is the NIH Exploratory/Developmental Research Grant — designed for novel, high-risk/high-reward research where preliminary data may be limited or absent. The total budget is capped at $275,000 in direct costs over the entire grant (typically split as $150K + $125K, but flexibility exists), and the maximum project period is 2 years.
Recent R21 awards (last 24 months)
Live data from NIH RePORTER3,977
Awards
$135,552,711
Total funding (sample)
$271,105
Average award
Sample reflects up to the most recent 500 NIH RePORTER awards with this activity code in the past 24 months. Total project count is the full RePORTER count.
Most recently awarded R21 grants
JEAN BIDLACK · UNIVERSITY OF ROCHESTER, NY · NIH
$192,500
FY 2026
Project: 5R21DA061044-02
Ziyad Ben Taleb · UNIVERSITY OF TEXAS ARLINGTON, TX · NIH
$247,878
FY 2026
Project: 1R21DA062897-01A1
Carrie Breton · WASHINGTON UNIVERSITY, MO · NIH
$427,625
FY 2025
Project: 7R21ES036649-02
Ravi Bharadwaj · UNIV OF MASSACHUSETTS MED SCH WORCESTER, MA · NIH
$251,250
FY 2026
Project: 1R21AI193666-01A1
Sarah Calve · UNIVERSITY OF COLORADO, CO · NIH
$348,339
FY 2026
Project: 1R21AR085969-01A1
NAGI AYAD · GEORGETOWN UNIVERSITY, DC · NIH
$429,000
FY 2026
Project: 1R21NS147326-01
Sheila Baker · UNIVERSITY OF IOWA, IA · NIH
$440,263
FY 2026
Project: 1R21EY037416-01A1
Ashley Brooks-Russell · UNIVERSITY OF COLORADO DENVER, CO · NIH
$248,201
FY 2026
Project: 1R21DA065027-01
Top NIH institutes funding R21
By total funding in the last 24 months
- 1.NIH494 · $134,541,310
- 2.ALLCDC5 · $871,032
- 3.AHRQ1 · $140,369
Top funded institutions
Most R21 awards in the last 24 months
- 1.JOHNS HOPKINS UNIVERSITY22 awards
- 2.WASHINGTON UNIVERSITY14 awards
- 3.UNIVERSITY OF CALIFORNIA, SAN FRANCISCO11 awards
- 4.MASSACHUSETTS GENERAL HOSPITAL11 awards
- 5.UNIVERSITY OF PITTSBURGH AT PITTSBURGH11 awards
- 6.YALE UNIVERSITY11 awards
Who applies for R21
When to choose R21
When NOT to choose R21
Search tips for R21
- R21 success rates vary widely — some institutes essentially treat them as small R01s with strict 2-year limits.
- An R21 awarded to a PI sometimes precedes an R01 in the same area within 2–3 years.
Search NIH grants by activity code
Find R21-funded PIs
R21 funding trends
R21 frequently asked questions
What is the page limit for an NIH R21?
The Research Strategy is 6 pages for an R21 (half of an R01).
Do I need preliminary data for an R21?
No. R21 funding announcements explicitly state preliminary data are not required. In practice, strong applications often include some, but the reviewers should not penalize lack of preliminary data per the funding mechanism design.
Can an R21 be renewed?
R21 awards are not renewable. The mechanism is designed for 2 years and out — typically followed by an R01 application if the work proceeds.
What is the typical R21 success rate?
R21 success rates have generally been similar to or slightly lower than R01 rates (typically 12–18%) in recent years. Variation by institute is large.