Basically, you buy your Authorize.net Payment Gateway account from a Reseller, who may also be a Merchant Service Provider (MSP), and the entity your merchant bank account uses to process your transactions is your Processor.

• Authorize.net acts as a bridge between your company and the financial entities that handle the processing and settlement of credit card transactions. Authorize.Net does not store your funds—we simply transfer them from the credit card issuing bank to your merchant bank account.
• Your Reseller is the entity from which you purchased your Authorize.Net account. A reseller can also be an MSP that provides transaction processing solutions (including the Authorize.Net Payment Gateway) to its merchant clients. Most merchants rely on resellers who provide all a merchant's payment processing needs in one place. In all likelihood, your reseller set up your Authorize.Net Payment Gateway account and your merchant bank account for you.
• Merchant Service Provider (MSP) is the company that acts as your Financial Institution. They deposit funds into your bank account for credit card processing and maintain your merchant account with Visa and MasterCard. They are also the company that charges you the percentage discount rate on your batch settlements. They may also assess transaction processing limits on your merchant account. Unless your MSP is CyberSource, Authorize.Net may be unable to determine who your MSP is due to the role in credit card processing that Authorize.Net fills. However, by looking at your credit card processing statements, you should be able to find who your Merchant Service Provider is, along with their contact information.
• Your Processor is an entity that processes credit card transactions for your acquiring bank. They post transactions for authorization, clear and settle consumer credit card accounts at the card associations, and settle funds to merchant bank accounts.
  
  NOTE: The bank that holds your merchant bank account is also known as your acquiring bank. Therefore, the acquiring bank's processor is your processor as well.

To fully understand how each of these entities works together to complete a transaction, please see How does the credit card transaction process work?

Since Authorize.Net is not a financial entity and is not directly involved in determining the financial policies that govern your transaction processing, we cannot provide guidance or resolution for transaction-related issues that may arise. As each of the organizations described above provides you with valuable services, it's helpful to know which company to contact with concerns regarding your transaction processing.

Contact Authorize.Net when:

1. You have questions regarding eCheck.Net® deposits, processing limits, batch settlement and reporting.
2. You have questions regarding your payment gateway configuration (any setting in the Merchant Interface).
3. You would like to add an additional Authorize.Net service such as Automated Recurring Billing (ARB)™ or Advanced Fraud Detection Suite (AFDS)™.

NOTE: Your bank will contact and work with your Processor as needed. You usually will not need to contact your Processor directly.

Contact your MSP when:

1. You need information about additional transaction processing services and adding credit card types.
2. You have questions regarding your merchant bank account deposits and statements, settlement reports, processing limits and fees, or your Processor configuration.

NOTE: In some cases your MSP may direct you to your merchant bank or even work together with your merchant bank to help resolve concerns and issues.

Contact your Reseller when:

1. You have questions about your MSP, transaction processing service fees, and payment gateway account or other payment services account activation and statuses.

NOTE: Your Reseller may be the same as your MSP. If not, your Reseller will be able to point you in the right direction if they are unable to help address your concerns or questions.