Account & Business Terms

What Is ISO/MSP? A Merchant's Guide

An Independent Sales Organization (ISO) or Merchant Service Provider (MSP) is a company registered with card networks to sell payment processing services.

The Complete Definition

An ISO (Independent Sales Organization) or MSP (Merchant Service Provider) is a company registered with Visa, Mastercard, or other card networks to sell payment processing services to merchants. ISOs act as intermediaries between merchants and acquiring banks.

ISOs must be registered with Visa and Mastercard and sponsored by an acquiring bank. The sponsoring bank takes on regulatory and compliance responsibility while the ISO handles merchant sales, onboarding, and day-to-day service.

ISOs come in two types: 1. **Registered ISO**: Directly registered with Visa/Mastercard. Can underwrite merchants, set rates, and take on direct liability. Requires significant capital and compliance infrastructure. 2. **Sub-ISO (or Agent)**: Works under a registered ISO. Can sell services but cannot directly underwrite merchants or customize rates without parent ISO approval.

The ISO model benefits merchants by providing: - Personalized service compared to large bank processors - Competitive pricing through volume aggregation - Industry expertise in specific verticals - Local or specialized support

ISOs earn revenue on the markup above interchange — typically 0.10%–0.40% of processing volume. They may also earn on equipment, monthly fees, and software add-ons.

How ISO/MSP Affects Your Processing Costs

Working with an ISO versus a bank-direct processor or an aggregator has tradeoffs. ISOs typically offer more personalized service and competitive pricing for established merchants. They may also be more flexible in underwriting non-standard businesses.

Verify any ISO you work with is properly registered with Visa and Mastercard. Registered ISO status is publicly verifiable through the card networks.

ISO/MSP Example

Liberty Bancard is a registered ISO/MSP with Visa and Mastercard:
- Sponsored by an acquiring bank partner
- Signs merchant agreements on behalf of the acquirer
- Sets pricing within parameters approved by the acquirer
- Manages merchant relationships, support, and onboarding
- Earns on the markup portion of interchange plus pricing

Common Questions About ISO/MSP

Is an ISO different from a payment processor?

An ISO is a reseller of payment processing services. They typically partner with a larger processing company or acquiring bank rather than maintaining their own processing infrastructure. The distinction matters for understanding where your fees go.

How do I verify an ISO is legitimate?

You can verify ISO registration directly with Visa and Mastercard — both maintain registries of approved ISOs. Always ask to see their registration credentials before signing any merchant agreement.

Related Terms

Registered ISOPayment FacilitatorPayment ProcessorAcquiring BankMerchant AccountPayFac vs. ISO

How Liberty Bancard Handles ISO/MSP

Liberty Bancard is a registered ISO/MSP with Visa and Mastercard. Our registration status means we're accountable to card networks and sponsoring banks for the quality and compliance of our merchant accounts. We don't operate in gray areas.

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