Small Business Innovation Research (SBIR) Small Business Technology Transfer (STTR)

NIH SBIR and STTR Application Types

The programs offer several different types of applications to accommodate the varying R&D needs of small businesses. You can find all of the solicitations below on our Funding page. Read more to find out which application is most relevant to your small business.

Phase I awards are intended to establish the technical merit, feasibility, and commercial potential of the proposed research and research and development (R/R&D) efforts. These applications help determine the quality of performance of the small business prior to providing further Federal support in Phase II. Phase I awards normally do not exceed $150,000 total costs for 6 months (SBIR) or 1 year (STTR).

If an applicant receives a Phase I award, they may submit a Phase II application either before or after expiration of the Phase I budget period. To maintain eligibility to seek Phase II support, a Phase I grantee should submit a Phase II application within the first six receipt dates following the expiration of the Phase I budget period. If the grantee is outside of the six receipt period timeframe, they must contact their Phase I program officer and if the program officer is willing to receive an application, a waiver may be granted. Phase I applications are considered new (Type 1) in the NIH grant numbering system.

Phase II awards are intended to continue the R/R&D efforts initiated in Phase I. Funding is based on the results achieved in Phase I and the scientific and technical merit and commercial potential of the project proposed in Phase II. Only Phase I awardees are eligible for a Phase II award. SBIR Phase II awards normally do not exceed $1,000,000 total costs for 2 years. Phase II applications are considered renewals (Type 2) in the NIH grant numbering system.

Fast-track incorporates a submission and review process in which both Phase I and Phase II grant applications are submitted and reviewed together as one application. Because both phases undergo review at the same time, the NIH Fast-Track mechanism can reduce or eliminate the funding gap between phases. Fast-track applications are considered new (Type 1) in the NIH grant numbering system.

Section 5106 of the SBIR/STTR Reauthorization Act of 2011 authorized that NIH may ‘issue a Phase II award to a small business concern that did not receive a Phase I award for that research/research & development'.  This 'phase flexibility' is called a ‘Direct-to-Phase II’ SBIR award. The SBIR Direct-to-Phase II authority is not available to the STTR program and not available for the CDC, FDA, and ACL SBIR programs. See

Phase IIB awards are intended to provide follow-on funding to small businesses for projects that require extraordinary time and effort in the R&D phase and may or may not require FDA approval for the development of projects such as drugs, devices, vaccines, therapeutics, and medical implants. Not all ICs offer Phase IIB awards, and depending on the IC, the budget may be requested for up to $1M per year for up to 3 years. For a full listing of those ICs that accept Phase IIBs, see the Omnibus Solicitation Program Descriptions and Research Topics document. Prospective applicants are strongly encouraged to contact NIH program staff prior to submission. Phase IIB applications are considered renewals (Type 2) in the NIH grant numbering system.

The Commercialization Readiness Program (CRP) may provide up to $3 million in additional funding for Phase II SBIR/STTR projects, and is not subject to the same partnering requirements that apply to SBIR or STTR awards. Therefore, the CRP may fund work that is not typically support through SBIR or STTR Phase II or Phase IIB awards, including:

For more information, please refer to the Commercialization Readiness Program (CRP) solicitations. You may also view the materials from the HHS CRP Informational Webinar (December 2, 2015).

  • Preparation of documents for a Food and Drug Administration (FDA) submission
  • Development of an intellectual property strategy
  • Investigational New Drug (IND)-enabling studies
  • Clinical studies
  • Manufacturing costs
  • Regulatory assistance
  • Subcontracted work to other institutions, including contract research organizations (CRO)
  • A combination of services
Decoding the NIH Grant Numbering System

Understanding how NIH classifies grants can help you figure out what NIH grant numbers mean and be helpful when you are using RePORTER, which is a database of NIH research projects that have been previously funded.

NIH uses activity codes (e.g. R01, R43, etc.) to differentiate the types of research-related grants that NIH awards and funds. Activity codes R41 and R42 are for STTR awards and R43 and R44 are for SBIR awards. Twenty-four of the 27 NIH Institutes and Centers (ICs) have SBIR and/or STTR programs. Please note that R41, R42, R43 and R44s are awards specifically designated for small businesses, but small businesses are still permitted to apply for other types of grants including R01s. For more information about all of the different types of grant programs that NIH offers, please click here.


Phase I Phase II











Note: U means "cooperative agreements"


An application that is submitted for funding for the first time. (Type 1).


Before April 16, 2014, NIH permitted one resubmission (A1) of an unfunded application (see NOT-OD-09-016). Resubmissions are considered amended, and have an A1 at the end of the grant number. The extension on the NIH grant number could follow the pattern (A0, A1). A first-time submission is informally referred to as an A0, and the first resubmission is known as an A1. Any virtual A2s would be flagged by the NIH Center for Scientific Review.

For all application due dates after April 16, 2014, following an unsuccessful resubmission (A1) application, applicants may submit the same idea as a new (A0) application for the next appropriate new application due date (see NOT-OD-14-082).

Resubmissions (A1) must be submitted within 37 months of the new (A0) application (see NOT-OD-10-140). The principal investigator (PI) must make significant changes to the application upon resubmission. An introduction must be included that summarizes the substantial additions, deletions and changes to the application and the substantial scientific changes must be marked in the text of the application by bracketing, indenting or change of typography.

For more details on the Resubmission Policy, visit the Resubmissions webpage and the Guide Notice, NOT-OD-14-074.


Request for additional funds for a current award to expand the scope of work. Revisions must go through a formal peer review process. Applicants should contact the awarding agency for advice on submitting any revision/supplement application. (Type 3).

To learn now NIH’s resubmission policy affects SBIR/STTR applicants, please view the FAQs.


Competing for additional years of funding to continue original project. (Type 2); Includes Phase II applications.

Application Type Activity Code Institute Code Serial Number Support Year Extension






A1 (amended application)


For a complete listing of NIH acronyms, please click here. To see a list of the 2-letter Institute codes, please click here.

CSR: Center for Scientific review

AOR: Authorized Organization Representative

eRA: Electronic Research Administration

FOA: Funding Opportunity Announcement

FFR: Federal Financial Report

GMO: Grants Management Offcer

IC: Institute and/or Center

NIH: National Institutes of Health

NoA: Notice of Award

OER: Offce of Extramural Research

PA: Program Announcement

PI: Principal Investigator

RePORT: Research Portfolio Online Reporting Tool

RFA: Request for Applications

RPG: Research Project Grant

SO: Signing Offcial

SRG: Scientifc Review Group

  1. = New
  2. = Renewal [Previous NIH term – Competing Continuation]
  3. = Revision [Previous NIH term – Supplement]
  4. = Extension
  5. = Non-Competing Continuation
  6. = Change of Organization Status (Successor-In-Interest) [e.g., name change, merger]
  7. = Change of Grantee or Training Institution
  8. = Change of Institute or Division (Type 5 transfer to another NIH IC)
  9. = Change of Institute or Division (Type 2 transfer to another NIH IC)

Did you know... You can track the history of a grant in RePORTER? The Institute and Center (IC) code and serial number connects all of the awards associated with a particular project. RePORTER offers a repository of NIH-funded research projects and access publications and patents resulting from that funding.