The R21 grant mechanism is intended to encourage exploratory/developmental research by providing support for the early and conceptual stages of project development. The NIH has standardized the Exploratory/Developmental Grant (R21) application characteristics, requirements, preparation, and review procedures in order to accommodate investigator-initiated (unsolicited) grant applications.

The R21 Parent Funding Opportunity Announcement (FOA) for investigator-initiated R21 applications can be found at PA-11-261 and articulates the policies and procedures that apply to this grant mechanism.

This website describes the use of the R21 and describes the NIH Institutes and Centers (ICs) that intend to accept such applications.

• You may request a project period of up to two years
• The combined budget for direct costs for the two year project period may not exceed $275,000. No more than $200,000 may be requested in any single year.
• The R21 can not be renewed
• One resubmission (A1) is allowed
• Introduction required for a resubmission is limited to one page.
• No preliminary data are required but may be included if available.
• The Research Strategy may not exceed 6 pages.

• Exploratory, novel studies that break new ground or extend previous discoveries toward new directions or applications.
• High risk high reward studies that may lead to a breakthrough in a particular area, or result in novel techniques, agents, methodologies, models or applications that will impact biomedical, behavioral, or clinical research.
• Projects should be distinct from those supported through the traditional R01 mechanism.

Projects of limited cost or scope that use widely accepted approaches and methods are better suited for the R03 small grant mechanism (see R03 announcement citation).

All investigators should consult the list of participating ICs (shown below) as well as the IC staff listed as contacts to determine if an R21 application is appropriate. Investigators are strongly encouraged to consult with the appropriate NIH program administrator about their proposed research project during the concept development stage of the application.

All R21 grant applications will be assigned to the ICs according to standard PHS referral guidelines and specific program interests. Applications that are assigned to an IC that does not participate in this program may be returned without review.

• NIH Institutes and Centers that accept Investigator-Initiated R21 applications in response to the Parent R21 Announcement - (PA-11-261): NCCAM, NEI, NHGRI, NIA, NIAAA, NIAID, NIAMS, NIBIB, NICHD, NIDA, NIDCD, NIDCR, NIEHS, NIMH, NINDS, NINR and NLM.

• NIH Institutes and Centers that DO NOT ACCEPT R21 applications in response to the Parent R21 Announcement but ONLY accept R21 applications in response to their specific funding opportunity announcements: FIC, NCI, NCATS, NIMHD, NHLBI, NIDDK, NIGMS, and ORIP.

Please email R211@mail.nih.gov.