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NMI (Network Merchants Inc.) is a payment gateway provider offering secure card processing solutions for merchants worldwide. NMI provides flexible payment processing with extensive integration options and support for multiple payment types.

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Setup

NMI provides a self-service sign-up for a sandbox account. To sign up for an account, visit the sign-up page and create an account.

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Connector configuration

After signing up with NMI, you can configure the connector in Gr4vy using one of the following methods:
  • Flow - Configure payment routing rules through your Gr4vy dashboard
  • API integration - Specify the payment_service_id when creating transactions to explicitly route payments to this connector

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Credentials

Configure the following credentials in the Gr4vy dashboard, which are obtained from your NMI administrator portal:
  • API Key - Your NMI security key, found in the NMI administrator portal under Options → Settings → Security keys
NMI Security Key

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Features

NMI supports the following features:
  • Delayed capture - Authorize a payment and capture it at a later time
  • Partial capture - Capture a portion of the authorized amount
  • Partial refunds - Refund a portion of the captured amount
  • Refunds - Refund a captured payment
  • Void - Cancel an authorized transaction before capture
  • Zero auth - Verify a card without charging it
  • Digital wallets - Support for Apple Pay, Google Pay, and other wallet integrations
  • Payment method tokenization - Store payment methods for future use outside of transactions
  • 3-D Secure - Pass-through 3DS authentication
  • Open loop (optional) - Open-loop card processing can be enabled if supported by your NMI account

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Supported countries

NMI supports transactions from buyers in the following countries:
Country codeCountry codeCountry codeCountry codeCountry codeCountry codeCountry codeCountry code
AEARATBEBOBRCACH
CLCNCOCYDEDKEEES
FIFRGBGRHKIDILIN
ITJPKRLTLULVMTMX
MYNLNONZPEPHPLPT
PYRUSESGSISKTHTR
TWUSZA

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Supported currencies

NMI supports processing payments in the following currencies:
Currency codeCurrency codeCurrency codeCurrency codeCurrency codeCurrency codeCurrency code
AEDARSAUDBOBBRLCADCHF
CLPCNYCOPDKKEURGBPHKD
IDRILSINRJPYKRWMXNMYR
NOKNZDPENPHPPLNPYGRUB
SEKSGDTHBTRYTWDUSDZAR

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Limitations

The following features are not supported by this connector:
  • Network tokens - Network tokenization is not supported
  • Over capture - Capturing more than the authorized amount is not supported
  • Partial authorization - Partial authorization is not supported
  • Settlement reporting - Automatic settlement reporting is not supported
Additional limitations include:
  • Open loop requires account feature - Open-loop recurring payments are not enabled by default. This feature requires your NMI account to have open-loop payments enabled. If your NMI account supports this feature, enable it in the Gr4vy dashboard when configuring your connector credentials.

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Integration

To accept card payments with NMI, use one of Gr4vy’s client-side integration methods to securely collect card details. Due to PCI compliance requirements, card data should never be sent directly to your servers. You can integrate using:
  • Embed - A pre-built, customizable payment form that handles the complete payment flow
  • Secure Fields - Embed card input fields for building custom payment forms while maintaining PCI compliance
  • Mobile SDKs - Native SDKs for iOS, Android, React Native, and other platforms
These methods handle card data collection and tokenization. Once the card details are collected and tokenized, create a transaction through the Gr4vy API, which routes the payment to your configured NMI connection based on your Flow rules or explicit payment_service_id parameter.