“You only pay if the proposal wins” sounds like the safest deal in grant writing. Sometimes it is. More often it shifts risk in ways that are not obvious until the award letter arrives. Here is how the two models work, where each one makes sense, and the rules that limit contingent fees on federal awards.
The three structures you will see
Flat fee. You pay a fixed amount for a defined scope, usually half at kickoff and half at submission. The writer’s incentive is to deliver the proposal on time and complete. Your cost is known before you start.
Flat fee plus success fee. A lower flat fee, plus a percentage of the award if the proposal is funded. The writer shares some of the risk and some of the upside. Most published offers in 2026 used 1% to 7% of the award.
Success fee only. No upfront payment; the writer takes a larger share of the award, and only if the proposal wins. This is the model that needs the most scrutiny.
Why success-fee-only is rarer than it sounds
Proposal preparation cannot be charged directly to an SBIR/STTR award budget (2 CFR 200.460 treats proposal costs as indirect costs). Whatever you owe the writer comes out of company funds, not the award. On a $275,000 Phase I, a 15% success fee is $41,250 of cash the company has to find after the award, while the money from the agency arrives on its own schedule.
The writer has to say no to most clients. A success-fee-only writer can only afford to work on proposals with a very high chance of winning. If your company is a first-time applicant without preliminary data, you will usually be turned down or quietly deprioritized.
Incentives drift toward volume. A writer carrying ten unpaid proposals has to spread time across all of them. A flat fee buys you a defined number of hours.
Federal contracts restrict it. SBIR awards from DoD, NASA and some other agencies are contracts, not grants, and FAR 52.203-5 (Covenant Against Contingent Fees) requires the contractor to warrant that no person was retained to solicit or secure the contract on a contingent fee basis, with exceptions for bona fide employees and established agencies. How that clause applies to proposal writers is a legal question for each company and its counsel, and it is one reason many consultants will not work on a pure contingency basis for contract-based SBIR programs.
When pay-upon-award makes sense
A mission-driven company with a strong technical team and no cash, applying to a grant-based program (not a FAR contract), where the writer has looked at the technology and agreed the odds justify the risk. In that situation a success-fee-only or low-flat-plus-success-fee arrangement can be the right call for both sides, with the terms written down: what the percentage applies to, when it is paid, and what happens if the company withdraws before submission.
When a flat fee is the safer choice
- You want a guaranteed number of hours and a delivery date.
- You are applying to a contract-based program (DoD, NASA).
- You expect to submit several proposals and want predictable costs.
- You would rather pay a known amount now than a larger unknown amount later.
How I handle it
Every engagement has a flat fee sized to the work. You can lower that flat fee by taking on an optional success fee that applies only if the grant is awarded. I do not work on a success fee alone, and I say so in the first call. The one exception is a small pilot for mission-driven marine companies applying to NOAA SBIR, where the terms are set in writing before any work starts.