--- updatedAt: 2026-09-02T15:10:31.000Z agentTools: projectIndex: https://docs.nmi.com/llms.txt --- # Billing Information Management > This documentation is intended for existing Classic API integrations. For new integrations, use the [Payment Component](../docs/payment-component) with the [REST API](../reference/create-sale-v5). If you're migrating from the Classic API, follow the [Classic API migration playbook](../docs/payment-migration-playbook).
Methodology **Steps:** 1. The customer sends their payment information to the merchant's web site. 2. The merchant web site posts the payment data to the Payment Gateway. 3. The Payment Gateway responds immediately with the results of the transactions. 4. The merchant web site displays the appropriate message to the customer. The communication method used to send messages to the Payment Gateway's server is the standard HTTP protocol over an SSL connection. In the Payment API method, the communications with the cardholder (Steps 1 and 4) are developed completely by the merchant and therefore are not defined by the Payment Gateway. Step 1 should simply collect the payment data from the cardholder and Step 4 should display the appropriate transaction receipt or declined message. In Step 2, transaction details should be delivered to the Payment Gateway using the POST method with the appropriate variables defined below posted along with the request. In Step 3, the transaction responses are returned in the body of the HTTP response in a query string name/value format delimited by ampersands. For example: `variable1=value1&variable2=value2&variable3=value3` ### Customer Vault The Customer Vault was designed specifically for businesses of any size to address concerns about handling customer payment information. Visa and MasterCard have instituted the Payment Card Industry (PCI) Data Security to protect cardholder data, wherever it resides, ensuring that members, merchants, and service providers maintain the highest information security standards. These associations have also deemed that merchants will be held liable for any breach of cardholder data. This has become a major concern for merchants who handle credit card or electronic check payments. The Customer Vault is designed for these merchants who desire to avoid the tremendous costs and resources involved in becoming PCI compliant under these circumstances. The Customer Vault does this by allowing merchants to transmit their payment information through a Secure Sockets Layer (SSL) connection for storage in our Level 1 PCI certified data facility. Once the customer record has been securely transmitted to the Customer Vault, the merchant can then initiate transactions remotely without having to access cardholder information directly. This process is accomplished without the merchant storing the customer's payment information in their local database or payment application.
Response Code Table | Code | Description | |:------|:-------------------------------------------------------------------| | 100 | Transaction was approved. | | 200 | Transaction was declined by processor. | | 201 | Do not honor. | | 202 | Insufficient funds. | | 203 | Over limit. | | 204 | Transaction not allowed. | | 220 | Incorrect payment information. | | 221 | No such card issuer. | | 222 | No card number on file with issuer. | | 223 | Expired card. | | 224 | Invalid expiration date. | | 225 | Invalid card security code. | | 226 | Invalid PIN. | | 240 | Call issuer for further information. | | 250 | Pick up card. | | 251 | Lost card. | | 252 | Stolen card. | | 253 | Fraudulent card. | | 260 | Declined with further instructions available. (See response text) | | 261 | Declined-Stop all recurring payments. | | 262 | Declined-Stop this recurring program. | | 263 | Declined-Update cardholder data available. | | 264 | Declined-Retry in a few days. | | 300 | Transaction was rejected by gateway. | | 400 | Transaction error returned by processor. | | 410 | Invalid merchant configuration. | | 411 | Merchant account is inactive. | | 420 | Communication error. | | 421 | Communication error with issuer. | | 430 | Duplicate transaction at processor. | | 440 | Processor format error. | | 441 | Invalid transaction information. | | 460 | Processor feature not available. | | 461 | Unsupported card type. |
### **Never Use Real API Keys** Use Sandbox keys with the Try It feature. Do not enter production API keys when testing.
# OpenAPI definition ```json { "openapi": "3.1.0", "info": { "version": "1.0.0", "title": "Payments", "x-logo": { "url": "https://www.nmi.com/app/themes/nmi/images/NMI_Logo_Primary.webp" } }, "servers": [ { "url": "https://sandbox.nmi.com/api" } ], "security": [], "tags": [ { "name": "Billing", "description": "Billing information management for customer billing details and preferences" } ], "externalDocs": { "url": "https://www.postman.com/nmi-integration-support/workspace/nmi-public-documentation/request/5480015-f4b0ec7b-bd84-4094-98c2-67c0b6508a7f", "description": "Public Documentation (Postman)" }, "paths": { "/transact.php": { "post": { "tags": [ "Billing" ], "summary": "Billing Information Management", "description": "
\nMethodology\n\n**Steps:**\n1. The customer sends their payment information to the merchant's web site.\n2. The merchant web site posts the payment data to the Payment Gateway.\n3. The Payment Gateway responds immediately with the results of the transactions.\n4. The merchant web site displays the appropriate message to the customer.\n\nThe communication method used to send messages to the Payment Gateway's server is the standard HTTP protocol over an SSL connection.\n\nIn the Payment API method, the communications with the cardholder (Steps 1 and 4) are developed completely by the merchant and therefore are not defined by the Payment Gateway. Step 1 should simply collect the payment data from the cardholder and Step 4 should display the appropriate transaction receipt or declined message.\n\nIn Step 2, transaction details should be delivered to the Payment Gateway using the POST method with the appropriate variables defined below posted along with the request.\n\nIn Step 3, the transaction responses are returned in the body of the HTTP response in a query string name/value format delimited by ampersands. For example: `variable1=value1&variable2=value2&variable3=value3`\n\n### Customer Vault\nThe Customer Vault was designed specifically for businesses of any size to address concerns about handling customer payment information. Visa and MasterCard have instituted the Payment Card Industry (PCI) Data Security to protect cardholder data, wherever it resides, ensuring that members, merchants, and service providers maintain the highest information security standards.\n\nThese associations have also deemed that merchants will be held liable for any breach of cardholder data. This has become a major concern for merchants who handle credit card or electronic check payments. The Customer Vault is designed for these merchants who desire to avoid the tremendous costs and resources involved in becoming PCI compliant under these circumstances.\n\nThe Customer Vault does this by allowing merchants to transmit their payment information through a Secure Sockets Layer (SSL) connection for storage in our Level 1 PCI certified data facility. Once the customer record has been securely transmitted to the Customer Vault, the merchant can then initiate transactions remotely without having to access cardholder information directly. This process is accomplished without the merchant storing the customer's payment information in their local database or payment application.\n
\n\n
\nResponse Code Table\n\n| Code | Description |\n|:------|:-------------------------------------------------------------------|\n| 100 | Transaction was approved. |\n| 200 | Transaction was declined by processor. |\n| 201 | Do not honor. |\n| 202 | Insufficient funds. |\n| 203 | Over limit. |\n| 204 | Transaction not allowed. |\n| 220 | Incorrect payment information. |\n| 221 | No such card issuer. |\n| 222 | No card number on file with issuer. |\n| 223 | Expired card. |\n| 224 | Invalid expiration date. |\n| 225 | Invalid card security code. |\n| 226 | Invalid PIN. |\n| 240 | Call issuer for further information. |\n| 250 | Pick up card. |\n| 251 | Lost card. |\n| 252 | Stolen card. |\n| 253 | Fraudulent card. |\n| 260 | Declined with further instructions available. (See response text) |\n| 261 | Declined-Stop all recurring payments. |\n| 262 | Declined-Stop this recurring program. |\n| 263 | Declined-Update cardholder data available. |\n| 264 | Declined-Retry in a few days. |\n| 300 | Transaction was rejected by gateway. |\n| 400 | Transaction error returned by processor. |\n| 410 | Invalid merchant configuration. |\n| 411 | Merchant account is inactive. |\n| 420 | Communication error. |\n| 421 | Communication error with issuer. |\n| 430 | Duplicate transaction at processor. |\n| 440 | Processor format error. |\n| 441 | Invalid transaction information. |\n| 460 | Processor feature not available. |\n| 461 | Unsupported card type. |\n\n
", "operationId": "manageBilling", "requestBody": { "content": { "application/x-www-form-urlencoded": { "schema": { "oneOf": [ { "$ref": "#/components/schemas/CreateBilling" }, { "$ref": "#/components/schemas/UpdateBilling" }, { "$ref": "#/components/schemas/DeleteBilling" } ] }, "examples": { "Create Billing": { "$ref": "#/components/examples/CreateBilling" }, "Update Billing": { "$ref": "#/components/examples/UpdateBilling" }, "Delete Billing": { "$ref": "#/components/examples/DeleteBilling" } } } } }, "responses": { "200": { "description": "Billing operation completed successfully", "content": { "application/x-www-form-urlencoded": { "schema": { "$ref": "#/components/schemas/Response" }, "examples": { "Billing Created": { "$ref": "#/components/examples/BillingCreated" }, "Billing Updated": { "$ref": "#/components/examples/BillingUpdated" }, "Billing Deleted": { "$ref": "#/components/examples/BillingDeleted" }, "Declined Request": { "$ref": "#/components/examples/DeclinedResponse" } } } } } } } } }, "components": { "schemas": { "SecurityKey": { "type": "string", "description": "API Security Key assigned to a merchant account. New keys can be generated from the merchant control panel in Settings > Security Keys" }, "CreditCard": { "type": "object", "properties": { "ccnumber": { "type": "string", "enum": [ "4111111111111111", "5431111111111111", "6011000991300009", "341111111111111", "30205252489926", "3541963594572595", "6799990100000000019" ], "description": "Credit card number.\n\n
\nAllowed Card Numbers:\n\n| Card Type | Test Card Number |\n|:------------------|:---------------------|\n| Visa | 4111111111111111 |\n| MasterCard | 5431111111111111 |\n| Discover | 6011000991300009 |\n| American Express | 341111111111111 |\n| Diner's Club | 30205252489926 |\n| JCB | 3541963594572595 |\n| Maestro | 6799990100000000019 |\n
" }, "ccexp": { "type": "string", "description": "Credit card expiration date.\n \nFormat: `MMYY`" } } }, "BillingDetails": { "type": "object", "properties": { "first_name": { "type": "string", "description": "Cardholder's first name." }, "last_name": { "type": "string", "description": "Cardholder's last name." }, "address1": { "type": "string", "description": "Card billing address." }, "city": { "type": "string", "description": "Card billing city" }, "state": { "type": "string", "description": "Card billing state.\n \nFormat: `CC`" }, "zip": { "type": "string", "description": "Card billing postal code." }, "country": { "type": "string", "description": "Card billing country code. *Country codes are as shown in ISO 3166-1 alpha-2*.\n \nFormat: `CC`" }, "phone": { "type": "string", "description": "Billing phone number." }, "email": { "type": "string", "description": "Billing email address." }, "company": { "type": "string", "description": "Cardholder's company." }, "address2": { "type": "string", "description": "Card billing address, line 2." }, "fax": { "type": "string", "description": "Billing fax number." } } }, "CreateBilling": { "type": "object", "title": "Create Billing", "allOf": [ { "required": [ "customer_vault", "customer_vault_id", "ccnumber", "security_key" ], "properties": { "security_key": { "$ref": "#/components/schemas/SecurityKey" }, "customer_vault": { "type": "string", "enum": [ "add_billing" ], "description": "Create a billing record for the given Customer Vault record." }, "customer_vault_id": { "type": "string", "description": "Specifies a Customer Vault id." }, "billing_id": { "type": "string", "description": "Specifies a billing id." } } }, { "$ref": "#/components/schemas/CreditCard" }, { "$ref": "#/components/schemas/BillingDetails" } ] }, "UpdateBilling": { "type": "object", "title": "Update Billing", "allOf": [ { "required": [ "customer_vault", "customer_vault_id", "billing_id", "ccnumber", "security_key" ], "properties": { "security_key": { "$ref": "#/components/schemas/SecurityKey" }, "customer_vault": { "type": "string", "enum": [ "update_billing" ], "description": "Update a billing record for the given Customer Vault record." }, "customer_vault_id": { "type": "string", "description": "Specifies a Customer Vault id." }, "billing_id": { "type": "string", "description": "Specifies a billing id. If not set" } } }, { "$ref": "#/components/schemas/CreditCard" }, { "$ref": "#/components/schemas/BillingDetails" } ] }, "DeleteBilling": { "type": "object", "title": "Delete Billing", "required": [ "customer_vault", "customer_vault_id", "billing_id", "security_key" ], "properties": { "security_key": { "$ref": "#/components/schemas/SecurityKey" }, "customer_vault": { "type": "string", "enum": [ "delete_billing" ], "description": "Delete a billing record for the given Customer Vault record." }, "customer_vault_id": { "type": "string", "description": "Specifies a Customer Vault id." }, "billing_id": { "type": "string", "description": "Specifies a billing id." } } }, "Response": { "type": "object", "title": "Response", "properties": { "response": { "type": "string", "enum": [ "1", "2", "3" ], "description": "Status code for the operation. (1) - success, (2) - failed, (3) system error" }, "responsetext": { "type": "string", "description": "Textual description of the operation's result." }, "authcode": { "type": "string", "description": "Authorization code for the operation." }, "amount_authorized": { "type": "string", "description": "(Conditional) This will optionally come back when requesting partial payment. Authorization amount." }, "transactionid": { "type": "string", "description": "(Conditional - Payment) Payment gateway transaction id." }, "invoice_id": { "type": "string", "description": "(Conditional - Invoice) Identifier for the invoice." }, "avsresponse": { "type": "string", "description": "Address Verification Service response code." }, "cvvresponse": { "type": "string", "description": "Card Verification Value response." }, "orderid": { "type": "string", "description": "Identifier for an order related to this invoice." }, "type": { "type": "string", "enum": [ "sale", "auth", "validate", "credit", "offline", "capture", "void", "refund", "complete_partial_payment", "add_invoice", "update_invoice", "send_invoice", "close_invoice", "add_plan", "edit_plan", "add_subscription", "" ], "description": "Type of operation that this response is for." }, "partial_payment_id": { "type": "string", "description": "(Conditional) This will optionally come back when requesting partial payment. A numeric identifier which is used when submitting subsequent transactions." }, "partial_payment_balance": { "type": "string", "description": "(Conditional) This will optionally come back when requesting partial payment. The payment's remaining balance." }, "platform_id": { "type": "string", "description": "Platform ID associated with the transaction." }, "response_code": { "type": "string", "description": "Another status or result code for the operation. See [Response Code Table](#section/Appendixes/Payment-API-Response-Codes)" }, "subscription_id": { "type": "string", "description": "(Conditional - Subscription) The subscription ID that was created" }, "emv_auth_response_data": { "type": "string", "description": "(Conditional) This will optionally come back when any chip card data is provided on the authorization. This data needs to be sent back to the SDK after an authorization." }, "payment_terms": { "type": "string", "description": "(Conditional - Invoice) The terms of payment for the invoice." }, "customer_vault_id": { "type": "string", "description": "(Conditional - Customer Vault) The original customer_vault_id passed in the transaction request or the resulting customer_vault_id created on an approved transaction.\n\nNote: Only returned when the \"Customer Vault\" service is active." }, "kount_score": { "type": "string", "description": "The Kount \"Omniscore\" indicating the level of risk on a given transaction. The higher the score, the lower the risk.\n\nNote: Only returned when the \"Kount\" service is active." } } } }, "examples": { "CreateBilling": { "summary": "Create Billing", "description": "Create Billing", "value": { "customer_vault": "add_billing", "customer_vault_id": "1622014144", "billing_id": "BillingId1", "ccnumber": "4111111111111111", "ccexp": "1234", "security_key": "6457Thfj624V5r7WUwc5v6a68Zsd6YEm" } }, "UpdateBilling": { "summary": "Update Billing", "description": "Update Billing", "value": { "customer_vault": "update_billing", "customer_vault_id": "1622014144", "billing_id": "BillingId1", "ccnumber": "4111111111111111", "ccexp": "1234", "security_key": "6457Thfj624V5r7WUwc5v6a68Zsd6YEm" } }, "DeleteBilling": { "summary": "Delete Billing", "description": "Delete Billing", "value": { "customer_vault": "delete_billing", "customer_vault_id": "1622014144", "billing_id": "BillingId1", "security_key": "6457Thfj624V5r7WUwc5v6a68Zsd6YEm" } }, "BillingCreated": { "summary": "Billing Information Created", "description": "Billing Information has been created", "value": { "response": "1", "responsetext": "Billing Information Added", "authcode": "", "transactionid": "", "avsresponse": "", "cvvresponse": "", "orderid": "", "type": "", "response_code": "100", "customer_vault_id": "1622014144" } }, "BillingUpdated": { "summary": "Billing Information Updated", "description": "Billing Information has been updated", "value": { "response": "1", "responsetext": "Billing Information Updated", "authcode": "", "transactionid": "", "avsresponse": "", "cvvresponse": "", "orderid": "", "type": "", "response_code": "100", "customer_vault_id": "1622014144" } }, "BillingDeleted": { "summary": "Billing Information Deleted", "description": "Billing Information has been deleted", "value": { "response": "1", "responsetext": "Billing Information Deleted", "authcode": "", "transactionid": "", "avsresponse": "", "cvvresponse": "", "orderid": "", "type": "", "response_code": "100", "customer_vault_id": "1622014144" } }, "DeclinedResponse": { "summary": "Failed to Create Plan", "description": "Failed to create a new plan", "value": { "response": "3", "responsetext": "There is already a plan using the SKU you have specified. REFID:1203610329", "authcode": "", "transactionid": "", "avsresponse": "", "cvvresponse": "", "orderid": "", "type": "", "response_code": "100" } } } } } ```