How is an ISO valued?

A whole ISO is valued as an operating business, typically on a multiple of EBITDA, in contrast to a bare residual stream, which is valued as a multiple of monthly residual. ISO EBITDA multiples run a wide range, roughly 6x to 18x, depending on growth, residual durability, portability, concentration, the strength of the sales engine, and how dependent the business is on the owner. The same ISO can land at very different points in that range depending on how it is prepared and how competitive the process is.

What is the difference between selling an ISO and selling a residual portfolio?

Selling a residual portfolio transfers an income stream; the merchants stay put and the seller usually walks away. Selling an ISO transfers a business: the residual base plus the sales organization, agent relationships, processor contracts, brand, and staff. ISO buyers pay for the machine that produces new merchants, not just the trailing income, which is why ISOs are valued on EBITDA while portfolios are valued on monthly residual.

What EBITDA multiple do ISOs sell for?

Roughly 6x to 18x EBITDA, with most transactions in the middle of that range. The high end goes to ISOs with strong organic growth, low attrition, diversified merchant bases, portable processor relationships, and management that stays. The low end goes to owner-dependent books with flat or declining residuals and concentration risk. Growth rate and residual durability move the multiple more than absolute size does.

What drives an ISO's valuation up or down?

Up: consistent new-merchant production, revenue attrition trending down, a diversified merchant base, clean and portable processor agreements, recurring tech or software revenue attached to processing, and a management team that runs without the owner. Down: attrition above the buyer's comfort level, one processor or a few merchants dominating the economics, agent agreements without assignment rights, and EBITDA that needs heavy adjustments to look attractive.

Should I sell my whole ISO or just the residual portfolio?

It depends on what you want next. Selling the portfolio raises cash while you keep operating and producing. Selling the ISO is a full exit and monetizes the sales engine as well as the income stream, usually at a larger total number. Some owners sequence it: sell a slice of residuals first, prove the relationship, then sell the company. The right answer follows from your timeline, your growth trajectory, and where your value actually sits: in the book, or in the machine that builds it.

How to Value an ISO | Residuals for Sale

By Lane Gordon, 733Park. Updated September 15, 2026.

733Park's rule of thumb: a whole ISO is valued as an operating business at roughly 6x to 18x EBITDA, with most transactions in the middle of that range, while a bare residual portfolio is valued at a multiple of net monthly residual; new-merchant production, attrition, merchant diversification and portable processor agreements decide where an ISO lands.

The most common valuation mistake ISO owners make is pricing their company like a residual portfolio: months of residuals, times the book. That framework undervalues a real ISO badly, because it prices the trailing income and ignores the sales engine. Here is how buyers actually value an ISO, and how to know which framework applies to you.

Two frameworks: residual multiple versus EBITDA multiple

A bare residual stream is valued as a multiple of net monthly residual. That is the right framework when the buyer is acquiring income and nothing else: no staff, no sales organization, no growth story. How that works is covered in how to value a merchant services portfolio and what sets a typical buyout multiple.

A whole ISO is valued as an operating business on a multiple of EBITDA, typically in a range of roughly 6x to 18x. The spread is wide because buyers are pricing very different things at each end: at the low end, a stream of income with a company attached; at the high end, a growth platform with recurring revenue, a producing sales force, and management that stays. Where you land in that range is mostly determined before the process starts.

What moves an ISO up the range

Organic growth. Consistent new-merchant production is the clearest separator between a book and a business. Buyers pay for the engine, and they verify it in diligence with monthly production detail.
Residual durability. Revenue attrition, trending in the right direction, across a diversified merchant base. The mechanics are the same ones covered in how attrition affects portfolio value, applied to the whole company.
Portability and contract quality. Processor agreements that transfer cleanly, agent agreements with assignment rights, and no single relationship that can veto the deal.
Revenue mix. Software, gateway, or other recurring technology revenue attached to processing earns a premium over processing-only economics.
A business that runs without you. Owner dependence is a discount buyers apply quietly. Management depth and documented operations move the multiple more than most owners expect.

What moves it down

Concentration is the big one: one processor relationship, a handful of merchants, or one agent producing most of the residuals. After that, attrition above the buyer's underwriting threshold, EBITDA that requires aggressive adjustments to look healthy, contracts missing assignment language, and any history that complicates the compliance story. None of these kills a sale; each one shaves the multiple or shifts price into holdbacks and earnouts. Structure mechanics are covered in how portfolio sales are structured.

Establishing real EBITDA

ISO EBITDA is rarely the number in the P&L. Buyers normalize it: owner compensation adjusted to market, one-time items removed, any residual streams the company does not actually own carved out, and revenue verified against processor statements. Do this normalization yourself before going to market, because a buyer who finds the adjustments first controls the narrative. A defensible adjusted-EBITDA schedule, tied to statements, is the ISO equivalent of the clean reporting package in preparing your portfolio for sale.

Which sale is right for you

If your value sits in the book and you are done building, a portfolio sale is simpler and faster. If your value sits in the machine, a company sale monetizes it, and the step-by-step process in how to sell a merchant portfolio applies with a heavier diligence load. Our sell your ISO page covers how the full-company process differs. Sequencing is also legitimate: some owners sell a residual slice first and the company later.

Get a number you can defend

Run your numbers through the free valuation calculator, which handles both frameworks: EBITDA-based for a whole ISO, residual-based for a stream. Then, before you anchor on any single offer, remember that the range is set by preparation and the final number is set by competition. Residuals for Sale, the residual and merchant-portfolio practice of 733Park, has 25+ years in payments M&A and 200+ closed transactions behind it. Talk to us confidentially and we will tell you which framework your business belongs in and what the current market is actually paying.

How to value an ISO