Technology readiness
Technology Readiness Levels (TRL 1–9), explained for federal applicants
Federal reviewers use Technology Readiness Levels to judge how far along your technology really is, and to decide whether the work you are proposing matches the money you are asking for. Here is the full nine-level scale in plain English, the evidence each level needs, and where SBIR funding fits.
The short answer
Technology Readiness Levels are a nine-point scale for technology maturity, created by NASA and adopted across US federal agencies. TRL 1–3 is research, TRL 4–6 is development and prototyping, TRL 7–9 is demonstration and live deployment. Most SBIR Phase I applicants sit at TRL 2–3 and finish around TRL 4; Phase II typically carries a company from TRL 4 to TRL 6.
- TRL 1–3
- Research: principles, concept and lab proof of the critical function.
- TRL 4–6
- Development: breadboard, then prototype, tested in a relevant environment.
- TRL 7–9
- Deployment: operational demonstration, qualification and live service.
Find your level on the scale
Select a level to see what it means, the evidence a reviewer expects to see, and which funding route fits.
TRL 3 · Research
Proof of concept
Analytical and laboratory work shows the critical function works — separately, not yet together. This is where most SBIR Phase I applicants sit.
Evidence reviewers expect
- Bench data on the critical component or function
- Modelling validated against a small experiment
- Characterisation of the key physical mechanism
Test environment
Laboratory bench
Funding fit
The classic SBIR Phase I entry point across NSF, NIH and DoD. Phase I money exists to move you from here to TRL 4.
The full TRL scale at a glance
| TRL | Definition | Environment | Typical funding |
|---|---|---|---|
| 1 | Basic principles observed | Paper and simulation only | Too early for SBIR. NSF's research grants, university programs and DOE Office of Science are the usual home. |
| 2 | Technology concept formulated | Paper and simulation only | Still early for SBIR. A strong Phase I usually needs at least preliminary data behind the concept. |
| 3 | Proof of concept | Laboratory bench | The classic SBIR Phase I entry point across NSF, NIH and DoD. Phase I money exists to move you from here to TRL 4. |
| 4 | Component validation in the lab | Laboratory, controlled conditions | A strong close to Phase I and a credible starting point for Phase II or a Direct to Phase II submission. |
| 5 | Component validation in a relevant environment | Simulated or relevant operational environment | Typical target for the end of an SBIR Phase I in hardware, and the mid-point of a Phase II. |
| 6 | System prototype in a relevant environment | High-fidelity relevant environment | The usual goal of an SBIR Phase II, and the level DoD program offices want before transition conversations get serious. |
| 7 | System prototype in an operational environment | Actual operational environment | Phase II sequential awards, DoD Phase III, ARPA-H milestone contracts and strategic partner co-funding. |
| 8 | System complete and qualified | Final configuration, expected conditions | Beyond most SBIR funding. Phase III contracts, procurement and commercial revenue take over here. |
| 9 | Proven in an operational environment | Live, in service | Commercial and procurement stage. Grant funding at this point targets new indications, new markets or the next generation. |
How TRL maps onto SBIR phases
Project Pitch and Phase I
Enter around TRL 2–3 with early data on the critical function, and exit around TRL 4 with an integrated breadboard. NSF Phase I awards up to $305K; NIH and DoD Phase I awards are typically $150K–$314K.
Phase II
Enter at TRL 4 and exit at TRL 6 with a prototype demonstrated in a relevant environment. NSF Phase II awards up to $1M; DoD Phase II commonly reaches $1.7M or more.
Direct to Phase II
For companies already at TRL 4–5 who can document that feasibility is proven. Offered by several DoD components and by NIH for specific topics.
Phase III and beyond
TRL 7 upward. Funded with non-SBIR money: defense program dollars, procurement contracts, strategic partners or revenue.
Award ceilings change with each solicitation. Confirm current figures on the NSF SBIR seed fund site or the agency's own solicitation before you plan a budget.
How each agency uses the scale
NASA
Created the original nine-level scale in the 1970s and formalised it in the 1990s. Still the reference definition most agencies borrow from.
NASA TRL definitionsDepartment of Defense
Uses the same nine levels with defense-specific wording around relevant and operational environments, alongside Manufacturing Readiness Levels (MRL 1–10).
DoD SBIR/STTR portalDepartment of Energy
Applies TRL to demonstration and scale-up projects, often paired with a commercial readiness view for energy technologies.
DOE SBIR programNIH and life sciences
NIH rarely asks for a TRL number directly and thinks in terms of discovery, IND-enabling work, and clinical phases. Map your TRL onto that language rather than quoting a number.
NIH SEEDFive TRL mistakes that cost applicants score
01
Claiming a level the data does not support
Reviewers read the evidence, not the claim. A stated TRL 6 backed by bench data reads as either careless or optimistic, and both cost you score on feasibility.
02
Confusing a relevant environment with a convenient one
A relevant environment reproduces the stressors that will break your technology. A bench with a heat lamp is not a thermal cycling chamber, and a spiked buffer is not plasma.
03
Skipping the jump from TRL 4 to TRL 6
This is the expensive middle where most deep-tech companies stall. SBIR Phase I and Phase II exist almost entirely to fund that stretch, so plan the work packages around it explicitly.
04
Using one TRL for the whole system
Systems are rarely uniform. Rate the critical subsystems separately and let the lowest one set your headline level — reviewers will find it anyway.
05
Ignoring manufacturing and regulatory readiness
A TRL 7 device with an unvalidated process or no regulatory path is not ready to transition. DoD tracks MRL alongside TRL for exactly this reason.
TRL questions founders ask us
What are Technology Readiness Levels?
Technology Readiness Levels (TRLs) are a nine-point scale that describes how mature a technology is, from TRL 1 where only the basic scientific principles have been observed, to TRL 9 where the system is proven in live operational use. NASA developed the scale and the Department of Defense, Department of Energy and many other agencies now use it to compare projects and set funding expectations.
What TRL do I need for an SBIR Phase I?
Most successful SBIR Phase I applicants are around TRL 2 to 3: the concept is formulated and there is early laboratory evidence for the critical function, but the pieces have not been integrated. Phase I funding is designed to take you to roughly TRL 4, and Phase II from TRL 4 to TRL 6.
Is TRL 4 or TRL 5 too advanced for SBIR?
No. If you are already at TRL 4 to 5 you may qualify for a Direct to Phase II award, which several DoD components and NIH offer, skipping the feasibility study entirely. You must be able to document that Phase I feasibility has effectively already been achieved.
What is the difference between a relevant environment and an operational environment?
A relevant environment reproduces the critical stressors of real use under controlled conditions — a thermal chamber, an animal model, a test range. An operational environment is the real setting itself, with the real users, timelines and interference. Moving from one to the other is the TRL 6 to TRL 7 step.
How do TRLs apply to software and AI?
The same logic holds with different evidence. TRL 3 is a working algorithm on curated data, TRL 5 is deployment against realistic data volumes and adversarial inputs, TRL 7 is running inside the user's live systems with their data governance and latency constraints in place.
How do TRLs map to drug and device development?
Roughly: TRL 1 to 3 covers target identification and hit-to-lead, TRL 4 to 5 covers lead optimisation and in vivo proof of concept, TRL 6 covers IND-enabling studies and GMP manufacture, TRL 7 covers first-in-human and clinical feasibility, and TRL 8 to 9 covers pivotal trials, approval and market use.
Free download
NSF SBIR Phase I readiness checklist and federal deadline calendar
Two pages, no email required. Every registration, eligibility test and proposal section you need before you write, plus the next deadline for NSF, NIH, DoD, DOE, NASA and USDA with the date you realistically need to start.
- 37-point readiness checklist
- Six agency deadlines with lead times
Know your TRL, unsure of the funding route?
Book a free consultation and we will tell you which agency and phase match your current evidence, before you write a word.