Retainer, Work Fee and Milestone Structures
Retainers, work fees and milestone fees are ways to fund advisory work as it is done. A success fee can sit on top of those structures when a defined closing occurs. For an unfunded sponsor, a success fee alone is not a structure. It is an attempt to shift the preparation cost.
Retainers, work fees and milestone fees are ways to fund advisory work as it is done. A success fee can sit on top of those structures when a defined closing occurs. For an unfunded sponsor, a success fee alone is not a structure. It is an attempt to shift the preparation cost onto the professional firm.
This guide does not set prices. It describes fee architecture so that advisory firms, law firms and other professionals can talk about terms without inventing numbers. Client-facing explanations already exist, including why structured finance advisors charge a retainer fee, debt placement fees, retainers and success fees, capital advisory retainers and why trade finance advisers charge retainers. Link to those pages rather than rewriting them.
What is the difference between a retainer, a work fee and a milestone fee?
A retainer secures a defined period of attention and starts paid work on a scoped file. A work fee pays for time or for a defined package of tasks. A milestone fee is due when a deliverable is completed, not when a lender funds. Each of these funds present work. A success fee, if used, rewards a later defined event.
| Structure | What it is meant to fund | What it is not |
|---|---|---|
| Retainer | A defined period of attention, intake, and the start of scoped work. | A payment for a promised loan, rating, legal outcome or credit approval. |
| Work fee | Time spent, or a defined package of tasks, billed as the work is done. | An open-ended promise to work until a close, without a paying client. |
| Milestone fee | A payment due when a stated deliverable is completed, such as a model or memorandum. | A renamed success fee that is due only if a lender or buyer says yes. |
| Success fee | An additional amount that becomes due if a defined closing or other stated event occurs. | A substitute for funding the work that has to happen before that event. |
These categories can be combined. Many serious mandates use a retainer or work fee to fund the process, and a success fee if a defined close is reached. The combination is ordinary. The failure mode is dropping everything except the success fee when the sponsor cannot pay for preparation.
When should a success fee be used, and when should it not be the only term?
Use a success fee as a complement, not as the only fee, when the sponsor can already fund preparation. Do not use it as the entire commercial deal with a sponsor who has no budget for diligence, models or legal work. In that case the firm is financing the client, not aligning with a closing.
A success fee can create useful alignment at the end of a process. It becomes a problem when it is asked to do the job of working capital. Models, legal drafting, customer due diligence and market preparation are not optional extras that can wait for a closing account. They are the process.
The same point is made from the borrower side in why no-upfront-fee debt advisory makes no economic sense and in success fees in debt raising. Advisors should not need those pages to see the cash-flow issue. They should be able to look at their own capacity plan and see that unpaid work crowds out funded work.
Can a milestone fee be tied to a financing close?
Yes, in principle, if the event is a completed deliverable such as a model, a memorandum or a diligence report. That is still a payment for work done. A milestone that is really 'when the bank says yes' is a success fee by another name, and it does not fund the work that precedes the bank's decision.
Language matters here. If the parties want a success fee, they should call it a success fee, define the event, and still fund the work that precedes it. If they want a milestone fee, they should attach it to work product the firm can actually complete, even if no capital provider later proceeds. Clarity in the engagement letter prevents a later argument about what was earned.
How does this article differ from existing retainer pages?
They explain, from the client's side, why a retainer exists and what it can cover. This article is written for the firms that have to design a fee architecture. It does not restate prices or schedules from those pages, and it does not invent new figures. Commercial numbers belong in an engagement letter, not in a generic guide.
Those existing pages remain the right place for a sponsor who wants to understand why a serious firm will not start unpaid. This page is the right place for a professional firm that is designing its standard terms, training staff, or explaining to a prospective client why a success-fee-only offer is not accepted. The two audiences should not be collapsed into one article.
Financely's own live commercial terms, including the paid intake, are described on Start Your Engagement. Other firms should not copy those figures. They should copy the idea that terms are written, scoped and paid, and that a deal submission is not itself a mandate.
How should the structure be documented?
Write the structure in the engagement letter, including what is payable if the mandate ends early and how expenses are treated. Be able to explain the structure in plain language. Where professional conduct rules apply, as with lawyers under ABA Model Rule 1.5, contingent terms generally need a clear writing and must be reasonable.
ABA Model Rule 1.5 is a useful reference even for readers who are not US lawyers, because it states the discipline clearly: fees must be reasonable, a contingent fee generally requires a signed writing, and the method of calculation, including expenses, should be stated. The SRA guidance on taking money for a firm's costs is a reminder, for solicitors, that money received before a bill is delivered may be client money and must be handled under the applicable accounts rules.
Advisors who are not lawyers still benefit from the same hygiene. Write the fee, write the scope, write the expenses, and write what happens if the work stops. Do not leave a success-fee-only conversation in email fragments and then start using the firm's name in the market.
What does a sound structure look like in practice?
A sound structure funds the work that will actually be done, names the payer, and treats any success fee as extra, earned only on a defined event. It also says how third-party costs are approved and paid. If those elements cannot be agreed, the firm does not yet have a mandate, and it should not behave as if it did.
Frequently asked questions
Can a firm use only a success fee with a funded sponsor?
It can, if the firm accepts the cash-flow and risk consequences and if applicable professional rules allow it. Even then, third-party costs still need a payer. With an unfunded sponsor, a success-fee-only term usually means the file cannot be prepared properly. That is why many firms refuse it.
Do you recommend specific percentages or retainers?
No. This article does not quote, invent or recommend any fee amount, percentage or hourly rate. Those figures depend on scope, jurisdiction, licenses and the engagement letter. Existing Financely pages discuss live commercial terms for Financely mandates. Other firms must set their own terms.
How should expenses and disbursements be treated?
They should be identified in the engagement and should have a payer other than the unpaid hope of a close. Counsel, travel, data, models and third-party reports are present costs. If the sponsor cannot fund them, the firm should not quietly absorb them in order to keep a speculative mandate alive.
Is a discounted retainer still a serious structure?
It can be, if it still funds the work the firm will actually do and if the scope is reduced to match. A token retainer that does not cover real preparation is close to a success-fee-only deal in substance. The test is whether present work is actually being paid for.
What if the sponsor wants every firm in the chain on the same success fee?
That request should be treated as a qualification issue. Law firms, technical advisors and other providers often cannot, and should not, wait for a closing to be paid. If the sponsor cannot fund that chain, the process is not ready, and the lead advisor should not pretend otherwise.
Where can clients read the borrower-facing explanation of retainers?
They can read why structured finance advisors charge a retainer, what a trade finance retainer covers, and the 2026 overview of debt placement fees. Those pages are written for clients. This page is written for professional firms that have to choose a structure before they start work.
Related reading
- Success-fee-only mandates from unfunded sponsors
- Engagement letter protections for finance advisors
- The opportunity cost of unpaid advisory work
If you have a real transaction and a budget for professional work, start with a paid intake. Financely is an advisor and arranger only. It does not lend and it does not issue credit.
Submit a deal Start your engagement
This article is educational. It is not legal, regulatory, tax or investment advice, and it is not an offer to lend, arrange or underwrite any transaction. Duties and permitted fee structures depend on the firm’s licenses, the jurisdiction and the engagement letter. Commercial terms are agreed in writing.
Sources
- ABA Model Rule 1.5, Fees
- SRA guidance, Taking money for your firm's costs
- Debt placement fees, retainers and success fees
- Why structured finance advisors charge a retainer fee
If the file is a trade finance request rather than a sponsor mandate qualification question, use the USD 500 trade finance eligibility screen. Intake and mandate terms remain on Start Your Engagement.