By Lane Gordon, 733Park. Published October 31, 2026.
733Park's rule of thumb: to sell a payments, fintech or SaaS company worth $5M to $350M, expect a success fee that runs from about 6 percent at the small end to about 2 percent at $100M, lower as the price rises, plus a monthly retainer that should be credited at closing. The percentage is the least important line in the agreement. The structure decides whether your advisor is paid to close your deal or paid to shop it, and who does the work decides the price.
733Park Fee Reference 2026: success fee by sale price, Firmex M&A Fee Guide 2023-24 (189 US M&A advisors) with 733Park's interpolation between its $5M, $20M and $100M points, checked against the competing engagement letters we see on $5M to $350M payments, fintech and SaaS sales. A market reference, not a quote. Cite as 733park.com/guides/what-a-sell-side-ma-engagement-costs.
The short answer
The success fee is a percentage of the sale price paid at closing out of proceeds. In the Firmex survey the typical fee was 6.3 percent on a $5M deal, 3.9 percent at $20M and 2.0 percent at $100M. Between those points, here is where a payments or software seller should expect to land:
| Sale price | Success fee, typical range | Fee in dollars | Source |
|---|---|---|---|
| $5 million | About 6.3% | About $315,000 | Firmex survey point |
| $10 million | About 4.5% to 5.5% | $450,000 to $550,000 | 733Park interpolation |
| $20 million | About 3.9% | About $780,000 | Firmex survey point |
| $30 million | About 3.0% to 3.5% | $900,000 to $1.05 million | 733Park interpolation |
| $50 million | About 2.7% to 3.2% | $1.35 million to $1.6 million | 733Park interpolation |
| $80 million | About 2.2% to 2.5% | $1.76 million to $2.0 million | 733Park interpolation |
| $100 million | About 2.0% | About $2.0 million | Firmex survey point |
Above $100M the percentage keeps falling and the engagement becomes a negotiation on structure rather than rate. Below $5M the percentage rises fast and the minimum fee, not the percentage, is usually the number that matters.
The four parts of a fee agreement
The success fee. The percentage above, paid at closing. Smaller deals carry higher percentages because the work of selling a $15M company is not much less than the work of selling a $150M company, while the fee base is ten times smaller.
The retainer. A monthly or upfront payment during the process. About three of four advisors in the survey charge one. Of those who bill monthly, two-thirds charge $5,000 to $10,000 a month, and a little over half of advisors credit what you paid against the success fee. Sellers sometimes bristle at retainers. In our experience the retainer serves both sides: it confirms the seller is serious, which matters when an advisor is deciding where to spend the next six months, and it filters out advisors who make their living collecting retainers on deals they never intend to close. The question is whether it is credited at close. If it is, incentives stay pointed at the closing table.
The minimum fee. A floor on the success fee regardless of price. Three of four advisors set one, and it matters most on smaller deals. It is also the line where a large bank and a boutique part company; more on that below.
The tail. The period after the engagement ends during which the fee is still owed if you sell to a buyer the advisor introduced. Ask how long it runs and whether it covers only buyers the advisor actually brought to you.
Three structures, and what each pays your advisor to do
About half of advisors use a declining scale, the Lehman formula and its variants, where the percentage steps down as the price steps up. About three in ten use one flat percentage. About one in six use an accelerator, where the percentage rises on value above an agreed threshold.
The accelerator is the one to study as a seller. Take a $30M sale with a $27M threshold, 3 percent below it and 6 percent above it. The advisor earns $810,000 on the first $27M and $180,000 on the last $3M. You keep $2.82M of that last $3M, and your advisor has been paid most for the dollars that were hardest to get. That is an illustration, not a quoted fee.
Success fee versus retainer: which should you push for?
Push for the structure where the advisor makes almost all of their money when you close, and where whatever retainer exists is credited against the success fee. A success-fee-only deal sounds seller-friendly, and sometimes it is, but it also tells you the advisor is not spending real senior time on your process, because nobody gives away six months of a principal's attention for free. A heavy retainer with a small success fee is the opposite problem: the advisor has been paid before a buyer signs anything. The balance that has worked across 200+ closings at 733Park is a modest retainer, fully credited at close, and a success fee that scales up on the dollars above your target. That keeps the advisor's incentive pointed at the last dollar of price, which is the dollar you care about.
What changes between a large investment bank and a boutique
Less than you would think on the percentage, and more than you would think on everything else. At $30M, a bank and a boutique will both quote you somewhere near 3 percent. The differences are in the other three parts. A large bank's minimum fee is set for the $500M deals its model is built on, so on a $30M sale it either prices you out or makes the percentage meaningless. Its retainer is usually larger and less often credited. And the team that runs your deal after the pitch is an associate running four others.
A boutique's minimum fee is calibrated to deals your size. The retainer is modest and credited. And the senior partner who pitched you is the person who calls the buyers, negotiates the letter of intent and defends the price in diligence. On a $30M software sale that is the whole difference: roughly $900,000 to $1.05M in fees either way, and one of the two has the buyer list for your category and the person who built the file on the phone when the deal wobbles at week fourteen. The full argument, including when the bank is the right answer, is here: Should I hire an investment bank or a boutique M&A advisor?
733Park's terms
A modest retainer credited at closing, and a success fee that rewards price above your target. The exact terms depend on the deal and are set in the engagement letter before any work starts. One rule that is the same on every engagement: if you already know up to three likely buyers, a sale to one of them carries a 20 percent fee reduction, and those buyers run inside the full process with everyone else. We do not run processes that leave parties out, because a process run around some of the buyers is the weaker process for the seller; the reduction is how we recognize what you brought to the table without weakening the auction.
What counts as the price
- Cash at closing only, or also earnouts, seller notes and rollover equity? If the fee applies to deferred consideration, is it paid when you receive it?
- In a merchant portfolio or ISO sale, where part of the price depends on attrition after the sale: is the fee on the full purchase price or on what is paid at closing?
- Is the retainer credited against the success fee, in full?
- How long is the tail, and does it cover only buyers the advisor introduced?
- What happens if you decide not to sell?
- Who does the work once the engagement letter is signed?
None of these are gotcha questions. A good advisor has crisp answers to all of them. The longer list is in the 10 questions to ask before hiring an M&A advisor.
Fees are the wrong thing to optimize
One point from 25 years of doing this: the difference between advisors is rarely the fee percentage. It is the outcome. A specialist who knows every serious buyer in your sector, runs a competitive process, and defends your number through diligence will routinely produce a price difference that dwarfs any spread in fees. Across 200+ deals and more than $10 billion in transaction volume, we have never seen a seller regret paying a full fee on a great outcome. We have seen plenty regret hiring the cheapest banker in the room.
The fee is one line in the math. What you keep is the number that matters, and that starts with what the business is worth. Run the valuation calculator, read what you keep after the sale, or start with a confidential conversation at 733park.com/contact.
Frequently asked questions
What does an M&A advisor charge to sell a company?
A success fee, a percentage of the sale price paid at closing, usually with a monthly retainer. Per the 733Park Fee Reference 2026, built on the Firmex survey of 189 US advisors, the typical success fee runs about 6.3 percent on a $5M sale, 4.5 to 5.5 percent at $10M, 3.9 percent at $20M, 3.0 to 3.5 percent at $30M, 2.2 to 2.5 percent at $80M and about 2.0 percent at $100M. Three of four advisors also set a minimum fee.
Success fee versus retainer: which is better for a seller?
A modest retainer credited in full against the success fee, plus a success fee that scales up on value above your target. Success-fee-only usually means less senior attention; retainer-heavy means the advisor has been paid before you are. About three of four advisors charge a retainer and a little over half credit it, so ask before you sign.
Should I use an investment bank or a boutique M&A advisor?
At $500M and up, the investment bank: you are a priority client and the machine works. At $5M to $350M, a specialized boutique usually gets the better outcome, because the fee percentage is about the same, the bank's minimum fee was set for much larger deals, and the person who runs the deal at a boutique is the senior partner who pitched it rather than an associate.
Boutique versus bulge-bracket for a $30M software sale: what is the difference in cost?
Little on the percentage, roughly 3.0 to 3.5 percent either way, or $900,000 to $1.05M. The difference is the minimum fee, which at a large bank is calibrated to $500M deals, the retainer, which is larger and less often credited, and who does the work. A boutique that lives in your category also brings the buyer list, which is what moves the price.
Do M&A advisors charge a retainer?
About three of four do. Of those who bill monthly, two-thirds charge $5,000 to $10,000 a month. Ask whether it is credited against the success fee; a little over half of advisors credit it.
What is a tail in an M&A engagement letter?
The period after the engagement ends during which the success fee is still owed if you sell to a buyer the advisor introduced. Ask how long it runs and whether it is limited to buyers the advisor actually brought to you.
Does the fee apply to earnouts and seller notes?
The engagement letter decides, so ask before you sign. The seller-friendly answer is that the fee on deferred consideration is paid when you receive it, and in a merchant portfolio or ISO sale, where part of the price depends on attrition, that the fee follows what is actually paid.
What does 733Park charge?
A modest retainer credited at closing and a success fee that rewards the price above your target, set in the engagement letter before work starts. If you already know up to three likely buyers, a sale to one of them carries a 20 percent fee reduction and those buyers run inside the full process with everyone else.
Sources: Firmex M&A Fee Guide 2023-24, survey of 189 US M&A advisors; 733Park Fee Reference 2026 (interpolation between the survey's $5M, $20M and $100M points). Ranges are a market reference, not a quote; 733Park's terms are set per engagement.