Why Some ISOs Draw a Line at All
Every submission takes real time, qualifying the merchant, gathering documentation, reading bank statements, working with a funder through underwriting and stips. That cost is largely fixed regardless of the deal’s size, which means a small deal returns a proportionally smaller commission for the same amount of work a much larger deal requires. Some ISOs respond to that math by drawing an explicit line under which they simply do not submit.
Others take every deal that qualifies at all, on the theory that volume adds up even at the small end. Neither approach is automatically correct, but the first one is a deliberate policy, and the second is often a default nobody decided on.
The Funder’s Own Floor Sets a Practical Minimum First
Most MCA providers already require $10,000 to $15,000 or more in verifiable monthly bank deposits before considering a deal at all, according to qualification criteria published by Crestmont Capital and corroborated by Nav’s own financing marketplace guide, though some accept revenue as low as $5,000 a month with the advance sized correspondingly smaller. That floor comes from competing brokers’ own published pages rather than one disclosed industry standard, so treat it as a typical range, not a universal rule every funder follows exactly.
Whatever an ISO’s own policy ends up being, it is layered on top of that existing funder-side floor, since a deal too small for any funder on the panel to consider is not really a policy decision at all, it is simply unfundable.
The Math Behind Why a Small Deal Costs More, Proportionally
The acquisition cost behind a submission, qualifying, documentation, underwriting time, follow-up, does not scale down meaningfully just because the funded amount does. A deal funded at $15,000 and a deal funded at $150,000 can take the broker nearly identical time to close, but the commission on the second is likely ten times larger. Treated purely as a return on time invested, small deals are structurally the least efficient part of a broker’s pipeline.
That efficiency argument is the real substance behind most minimum-deal-size policies, even when a broker states the cutoff as a round number rather than the underlying math.
Where the Round-Number Cutoff Comes From
This is reasoning, not a cited statistic. No funder or trade body publishes a recommended minimum deal size for ISOs, which is why the exact number varies broker to broker. A shop typically arrives at its own cutoff by tracking, informally or explicitly, how much time small deals consume relative to what they pay out, then setting a line somewhere above the point where that trade stops making sense.
A round number like $20,000 is less a market standard and more a broker’s own break-even point, expressed as policy.
What Gets Lost by Setting the Bar Too High
A minimum that is set purely on efficiency grounds risks screening out merchants who could become larger, repeat customers later, or referral sources, even if their first deal is small. A strict cutoff applied without exception treats every small deal as equally low-value, when some of them are the first transaction in a much longer relationship.
That is a real cost worth weighing against the efficiency argument, not a reason to abandon a minimum entirely, but a reason to build in judgment rather than a hard, unbending rule.
Building Flexibility Into the Policy
A minimum with room for exceptions, a referral partner’s client, a merchant likely to grow quickly, a relationship worth investing in beyond the immediate commission, captures most of the efficiency benefit of a hard floor without the rigidity that turns away every genuinely promising small deal. The exception should be the deliberate choice, not the default that swallows the policy entirely.
Human + AI SDRs qualify a merchant’s revenue and fit before a meeting ever lands on your calendar, so a minimum deal size policy can be enforced at the source instead of discovered halfway through underwriting a deal that was never going to clear the bar.
Sources
The external data in this guide draws on the sources below. Figures described in the text as estimates or industry triangulations are directional and are not attributed to a single dataset.
- Crestmont Capital, Merchant Cash Advance Requirements: How to Qualify for an MCA in 2026
- Nav, Merchant Cash Advance (MCA) Guide for 2026