TLDR
An Independent Sales Organization, or ISO, is a third-party company that sells merchant payment services on behalf of acquirers, processors, or PSPs.
What is an independent sales organization?
An independent sales organization, or ISO, is a third-party company that sells payment services to merchants on behalf of an acquiring bank, payment processor, or payment service provider.
ISOs usually help merchants get access to payment acceptance services, such as card processing, payment terminals, online payments, merchant accounts, and related payment products. They act as a commercial partner in the payment ecosystem rather than as the main financial institution behind the transaction.
In simple terms, an ISO helps payment providers acquire and support merchants.
How does an ISO work?
An ISO typically signs an agreement with an acquiring bank, processor, or PSP. Under this agreement, the ISO can market payment services, refer merchants, help with onboarding, and sometimes provide customer support or account management.
The exact role depends on the business model. Some ISOs only refer leads to a licensed provider. Others manage a larger part of the merchant relationship, including sales, onboarding assistance, pricing discussions, technical support, and ongoing account management.
The acquiring bank, processor, or PSP usually remains responsible for regulated payment processing, underwriting, settlement, risk controls, and compliance requirements, depending on the structure.
What services can an ISO provide?
An ISO may provide services such as:
- merchant acquisition;
- sales and referrals;
- payment product consulting;
- merchant onboarding support;
- payment terminal or POS distribution;
- online payment setup;
- basic technical support;
- account management;
- pricing and contract coordination;
- support with payment provider selection.
Some ISOs specialize in specific industries, merchant sizes, geographies, or risk profiles.
ISO vs payment processor
An independent sales organization and a payment processor play different roles. A payment processor handles the technical processing of payment transactions between merchants, acquirers, issuers, and payment networks.
An ISO focuses mainly on selling or distributing payment services to merchants. It may help merchants access processing services, but it does not usually process transactions itself unless it also operates as a processor or PSP.
In simple terms, a processor moves transaction data and supports payment processing. An ISO helps bring merchants into the payment system.
ISO vs PSP
A PSP provides payment services directly to merchants, such as payment acceptance, transaction processing, payment methods, reporting, and sometimes fraud tools, routing, or payouts.
An ISO usually acts as a sales or distribution partner for a PSP, processor, or acquiring bank. It may own the merchant relationship commercially, but the underlying payment services are usually provided by another regulated or technical provider.
Some companies start as ISOs and later expand into PSP-like services by adding technology, white-label infrastructure, or stronger operational capabilities.
Why ISOs matter
ISOs are important because they help payment providers reach more merchants and help merchants find suitable payment services.
For merchants, an ISO can simplify the process of comparing providers, setting up payment acceptance, understanding fees, and getting support. For acquirers, processors, and PSPs, ISOs can extend sales reach and provide market-specific knowledge.
ISOs are especially common in competitive payment markets where merchants need guidance on pricing, payment methods, risk requirements, provider coverage, and onboarding.
ISOs and payment infrastructure
An ISO can operate with a simple referral model, but more advanced ISOs often need stronger payment infrastructure to manage merchants, providers, payment flows, reporting, and support.
As an ISO grows, it may want to offer more branded services, manage more of the merchant experience, or become closer to a PSP model. This usually requires tools for merchant onboarding, transaction visibility, provider connectivity, routing, payouts, reconciliation, and analytics.
Corefy supports this growth by helping payment businesses connect providers, manage payment flows, monitor transactions, and run more controlled payment operations across merchants and markets.
Related terms
Go deeper
- Blog post
ISO/MSP in payments: what they are and how the model works
What an ISO does, how it differs from an MSP, and which network registration category applies.
- Blog post
How to start a merchant services or payment processing company
The ISO/MSP path to launching a merchant services business, and how it earns from referrals.