SBIR vs. STTR - What's the Difference? A Complete Comparison
The Two Most Valuable Small Business Grant Programs
SBIR and STTR are the two largest federal grant programs specifically designed for small businesses engaged in research and development. Together, they distribute over $4 billion annually to small businesses across every technology sector imaginable - from agricultural biotechnology to quantum computing to medical devices to defense systems.
Both are competitive, merit-reviewed programs. Both pay you to do R&D that you own the intellectual property to. Both have the same three-phase structure. The difference comes down to one requirement: the involvement of a research institution.
What Is SBIR?
The Small Business Innovation Research (SBIR) program requires that the primary R&D work be conducted by the small business itself. Your company can hire subcontractors and consultants, but the majority of the work must be performed by employees of your business.
Key eligibility requirements:
- For-profit, U.S.-based small business
- Fewer than 500 employees
- At least 51% owned and controlled by U.S. citizens or permanent residents
- Principal Investigator (PI) must be primarily employed by the small business during the project period
What Is STTR?
The Small Business Technology Transfer (STTR) program requires a formal cooperative research partnership between the small business and a nonprofit research institution - a university, federally funded research and development center (FFRDC), or nonprofit research organization.
Additional requirements beyond SBIR:
- At least 30% of the project work must be performed by the partnering research institution
- At least 40% of the work must be performed by the small business
- The PI can be employed by either the small business or the research institution
- The partnership must have a formal agreement covering intellectual property rights
Phase Structure (Same for Both Programs)
Phase I - Feasibility
Phase I is designed to establish the technical merit and feasibility of your proposed innovation. Award amounts vary by agency but typically range from $150,000 to $300,000 over 6 to 12 months. The deliverable is a Phase I Final Report demonstrating technical feasibility and a plan for commercialization.
There is no requirement to have a commercial product - Phase I funds the research to prove your idea can work.
Phase II - Research and Development
Phase II funds the actual R&D work based on the results of Phase I. Awards typically range from $750,000 to $2,000,000 over two years. Only Phase I awardees can apply for Phase II. The deliverable is a working prototype, proof of concept, or advanced research results, plus a detailed commercialization plan.
Phase III - Commercialization
Phase III receives no SBIR/STTR funding. It represents the transition of your innovation to commercial markets or (for defense/national security work) to federal procurement. Phase III often involves follow-on contracts from the same agency that funded Phases I and II, or private investment.
Which Agencies Participate?
Eleven agencies participate in SBIR; five participate in STTR:
- Both programs: DOD, HHS (NIH), DOE, NSF, NASA
- SBIR only: USDA, EPA, DOEd, DOT, DHS, and the National Oceanic and Atmospheric Administration
The Department of Defense (through its components like Army, Navy, Air Force, DARPA, and others) is the single largest SBIR/STTR funder, responsible for roughly half of all program spending. NIH is the second largest.
How to Find SBIR/STTR Opportunities
Agencies issue solicitations - essentially a list of topics they want innovators to address - on rolling and annual schedules. Resources:
- sbir.gov - the official government portal listing all open SBIR and STTR solicitations across all agencies
- GrantMine - search "SBIR" or "STTR" to see active opportunities pulled from Grants.gov nightly
- Individual agency websites - DOD's SBIR portal (dodsbirsttr.mil) and NIH's SEED office have their own interfaces
SBIR vs. STTR: Which Should You Apply For?
| Factor | SBIR | STTR |
|---|---|---|
| Research institution required? | No | Yes (30%+ work) |
| PI must work for small biz? | Yes (primary employment) | No (can be at university) |
| Best for | Established small biz teams | University spinouts |
| IP agreement required? | No | Yes |
Choose STTR if: Your innovation originated in a university lab, your PI is a faculty member who can't leave their position, or the research genuinely requires sustained access to university equipment or expertise.
Choose SBIR if: Your team is primarily based in your company, you want to maintain cleaner IP ownership, or the agency you're targeting only offers SBIR (DOT, EPA, USDA, DHS).
Realistic Expectations
SBIR/STTR Phase I acceptance rates typically range from 15–25% at most agencies. Phase II acceptance rates are higher (50–70%) because agencies are invested in prior Phase I awardees. The process from application to funding is slow - 6 to 9 months from submission to Phase I award is common. Plan accordingly.