Direct comparison
SBIR vs. STTR: Key Differences
STTR requires a formal small-business/nonprofit-research partnership with fixed work-share minimums; SBIR does not. Compare eligibility and TTO relevance.
Side-by-side comparison
| Dimension | SBIR | STTR |
|---|---|---|
| Full name | Small Business Innovation Research | Small Business Technology Transfer |
| Established | 1982 (Small Business Innovation Development Act, P.L. 97-219) | 1992 (Small Business Technology Transfer Act) |
| Research-institution partnership | Optional (voluntary subcontract) | Mandatory, formally documented, every funded phase |
| Small-business work-share minimum | 2/3 (66.7%) in Phase I; 1/2 (50%) in Phase II | At least 40% (fixed minimum, both phases) |
| Research-institution work-share minimum | No minimum -- purely discretionary | At least 30% (fixed minimum, both phases) |
| PI employment | Must be primarily employed by the small business | May be employed by either the small business or the research institution |
| Prime awardee | Small business (university cannot be prime) | Small business (university cannot be prime) |
| Participating agencies | 11 agencies | 5 of those 11 (DoD, HHS/NIH, DOE, NASA, NSF) |
| Statutory set-aside minimum | At least 3.2% of qualifying extramural R&D budget | At least 0.45% of qualifying extramural R&D budget (higher agency-budget threshold applies) |
| Phases | I (feasibility), II (full R&D), III (commercialization, separately funded) | Same three-phase structure |
| Funding type | Non-dilutive (grant/cooperative agreement/contract) | Non-dilutive (grant/cooperative agreement/contract) |
| Reauthorization status (2026) | Reauthorized through Sept. 30, 2031 (S. 3971) | Reauthorized through Sept. 30, 2031 (S. 3971), same act |
Common questions
FAQ
Can a small business choose either SBIR or STTR for the same project?+
Not freely. A proposal without a formal research-institution partnership must go through SBIR. A proposal built around such a partnership generally applies through STTR at agencies that offer it -- the two are not interchangeable wrappers around identical eligibility.
Does a voluntary university subcontract under SBIR count as an STTR-style partnership?+
No. An SBIR subcontract is a business choice with no fixed work-share guarantee, no formal partnership documentation requirement, and none of STTR’s PI-employment flexibility.
Is STTR always better for a university than SBIR?+
Not necessarily. STTR guarantees the university a protected role and budget share, but only 5 agencies offer it, and some faculty founders prefer the flexibility of an SBIR subcontract without a fixed percentage. Agency fit and how much work the university genuinely needs to perform both matter.
Do SBIR and STTR have different funding caps?+
The two programs largely share the same statutory guideline ceilings; differences are usually agency-specific solicitation choices rather than a difference built into the statutes themselves. Check the current agency solicitation for exact figures.
Going deeper
