ISO commission split structures explained, with the math

An agent agreement in merchant services looks simple from a distance: the agent gets a percentage of the residual. Up close, offices combine several different mechanisms, and two agreements with the same headline percentage can pay very different amounts. This guide goes through the six pieces in common use, with a number for each, and then the details that decide whether an agreement works in practice.

Throughout, residual means the monthly profit on a merchant after the processor's costs, as covered in How to calculate ISO residuals.

The six structures at a glance

Most real agreements use two or three of these together.

1. Flat split

The agent receives a fixed percentage of the residual on their merchants. On a merchant producing a $172.40 residual, a 50% agent earns $86.20 and a 70% agent earns $120.68.

It is easy to explain and easy to audit. The only real decision is the base: the percentage of what. Total Profit on the merchant, the ISO's share after the processor's split, and what remains after the office's own deductions are three different numbers, and the same 50% gives three different payouts. Put the base in the agreement in plain words. The residual split calculator shows the same percentage on all three.

2. Tiered split

The percentage rises as the agent's production grows, measured by monthly residual, processing volume or number of active merchants.

The detail that matters is whether tiers are marginal or retroactive. Take an agent producing $12,000 of residual a month on a plan that pays 50% up to $10,000 and 60% above it.

Same plan on paper, $1,000 a month apart. Retroactive tiers also create a cliff: an agent at $9,900 earns $4,950, and one more small merchant takes them to $6,000 or so. That is a strong incentive, which may be what you want, but it also means a single lost merchant can cut an agent's pay sharply, and they will notice. Decide which you mean, and state it.

Also decide what the tier is measured on. A tier based on the trailing three months is steadier than one recalculated every month.

3. Upfront bonus with a lower split

The agent is paid cash for each approved or activated account, and takes a smaller share of the residual in return. It gives a new agent income while their portfolio is still small.

Compare two offers on a merchant that produces a $100 monthly residual: 60% with no bonus, or 40% with a $300 bonus.

• 60% pays $60 a month.
• 40% pays $40 a month, plus $300 on day one.
• The difference is $20 a month, so the bonus is "repaid" after 15 months. After that the agent is behind for the life of the merchant.

Bonuses nearly always come with a clawback: if the merchant closes or stops processing within a set period, commonly six to twelve months, the bonus is taken back from future residuals. Track the clawback window per merchant from the start. Reconstructing it later from memory is where disputes begin.

4. Split by income type

An ISO rarely earns from processing alone. Equipment leases and rentals, gateway and software fees, cash advance referrals and point-of-sale subscriptions each have their own margin, and it is common to pay a different percentage on each. An agent might be on 60% of processing residuals, 30% of software income and a flat referral fee on funding deals.

This is sensible, and it is also where a single-column spreadsheet stops coping. Each report has to be tagged with its income type, and each agent needs a rate for each type, with a default for anything new.

5. Overrides and sub-agent structures

An override pays an upline on business sold by someone below them: a sales manager over a team, a master agent over sub-agents, or a recruiter over the people they brought in.

There are two common definitions, and they are not interchangeable. On a $172.40 residual with a 50% agent earning $86.20:

Three more things to settle in writing:

• Who funds it. In most offices the override comes out of the house share, so the agent's pay is unchanged. Some agreements carve it out of the agent's side. The agent will want to know which.
• How many levels. With two or more levels, check the total. An agent at 60%, a manager at 10 points and a regional lead at 5 points leaves the house 25% before any costs.
• What happens when the upline leaves. Does the override end, pass to their replacement, or return to the house?

6. Shared merchants

When two agents close a deal together, or an account is handed from one agent to another with a tail, each agent owns a share of the merchant. With a 60/40 share on a $172.40 residual, the first agent's split applies to $103.44 and the second's to $68.96. Each agent keeps their own percentage; only the base is divided.

A shared merchant is not an override. An override pays someone on another person's production. A share divides ownership of the account itself. Mixing the two up is a common source of double payment.

The one rule that must hold: the shares on a merchant add up to 100%, never more.

The details that decide whether it works

Total allocation. For every merchant, add the agent split, all overrides, and any referral or affiliate fees. If the total can exceed 100% of the residual under any combination, the house will eventually pay out money it did not receive.

Deductions before or after the split. If the office charges a gateway fee, a software fee or a referral fee against a merchant, say whether it comes off before the agent's percentage is applied or after. Before means the agent shares the cost. After means the house carries it.

Effective dates. Splits change. Record the date each rate starts, and keep the old one. If you overwrite a rate in place, you can no longer reproduce any earlier month, and an agent asking about last spring gets an answer based on this autumn's terms.

Vesting and what happens on exit. Agreements differ widely on whether residuals continue after an agent leaves, whether they continue only above a minimum monthly amount, and whether the ISO has the right to buy the agent's residual stream. None of this affects the monthly math until the day it suddenly does, so it belongs in the agreement from the start.

Minimums and negative months. A merchant can produce a negative residual in a month, from a chargeback or an annual fee. Decide whether the agent shares the loss, and whether negative balances carry forward.

A checklist for writing a split down

1. The percentage, and the exact base it applies to.
2. Whether tiers are marginal or retroactive, what they are measured on, and over what period.
3. Rates by income type, and the default for a new type.
4. Bonus amount, what triggers it, and the clawback window.
5. Overrides: percentage, base, who funds it, and what ends it.
6. Shares on jointly owned merchants, totalling 100%.
7. Which deductions come off before the split.
8. The effective date of every term.
9. What happens to residuals when the agent leaves.

Frequently asked questions

What is a typical ISO agent split? Splits commonly fall between 50% and 80% of the residual. Higher splits usually come with less support and no upfront bonus. Compare offers by working out the monthly payout on the same example merchant, not by comparing percentages.

What is an override in merchant services? An override is a payment to an upline, such as a manager or master agent, based on merchants sold by an agent beneath them. It is defined either as a percentage of the agent's commission or as points on the residual itself, and the two give different amounts.

Are tiered residual splits retroactive? Only if the agreement says so. With retroactive tiers, reaching a threshold raises the rate on the whole portfolio. With marginal tiers, the higher rate applies only to the amount above the threshold. The difference can be thousands of dollars a year for one agent.

How do clawbacks work on upfront bonuses? If a merchant closes or stops processing within the clawback window, commonly six to twelve months from approval, the bonus paid for that merchant is deducted from the agent's future residuals.

Can software handle all of these structures together? SplitRun applies a rate per agent per income type, shared merchants, overrides, deductions in a set order, and dated rate changes, and shows each agent the result in their own statement. The setup is described in Commission agreements and effective dates, Overrides and Shared accounts.