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Payments API (1.0.27)

The Payments API provides a single, secure interface for accepting and managing payments across credit cards, ACH transfers, and Apple Pay. It is designed to simplify integration, reduce risk, and give your team consistent tools for handling every stage of the payment lifecycle.

The Payments API follows modern REST conventions and uses JSON for requests and responses, making it straightforward to integrate from any language or platform. A single endpoint and a shared field model mean you can start with one payment type and expand to others with minimal additional development.

Built-In Security and Compliance

Security and compliance are built in. Tokenization protects sensitive data and aligns with the latest PCI DSS and Nacha security standards. Because payment details never touch your servers, a merchant’s compliance scope is reduced, and cardholder or account data is safeguarded.

Key Features

  • Data masking to protect sensitive information during processing and storage.
  • Rate limiting to ensure reliability, control usage, and mitigate fraud.
  • Field-level validation to catch errors in real time, reduce declines, and improve the user experience.
Download OpenAPI description
osi-payments-api.json
osi-payments-api.yaml
Languages
Servers
Mock server

https://docs.nelnetpay.com/_mock/apis/osi-payments-api/

UAT

https://api.uat.nelnetpay.com/payments-api/

Process a Payment Request

Request

Perform a request to process a payment.

This endpoint uses a valid Bearer Authentication API Key ID and HMAC Key for authentication.

Security
bearerAuth
Headers
nps-trace-uuidstringrequired
Authorizationstringrequired
Bodyapplication/jsonrequired
entityIdinteger(int64)required

A unique ID assigned by NPS that represents the client.

Example: 1325691045
paymentTypeobjectrequired
paymentType.​achobject
paymentType.​creditCardobject
paymentType.​applePayobject
transactionTypestringrequired

Indicates the type of transaction.

Enum"AUTH_ONLY""CAPTURE""SALE""REFUND""VERIFY""VOID""CANCEL""ACH_DEBIT""ACH_CREDIT""ACH_CANCEL"
Example: "AUTH_ONLY"
amountnumber

Amount of the transaction in BigDecimal.

Example: 123.65
accountHolderobject
transactionInformationobject
payfacobject
credentialsOnFileobject
additionalAmountArray of objects

Additional amount that is added to the amount of the cardholder's original transaction.

riskIdstring

A unique ID returned by the Risk Service.

Example: "12e3cdac-d347-4564-ba1f-305e5e1e8ded"
processingModestring

Mandatory for ACH transactions.

For transactions where the merchant sets the processingMode field value to SYNCHRONOUS, we will process these transactions in real-time using existing flows.

For transactions where the merchant sets the processingMode field value to ASYNCHRONOUS, we will process these transactions asynchronously.

We will queue the transaction for processing later.

Format Type: String

Enum"SYNCHRONOUS""ASYNCHRONOUS"
Example: "SYNCHRONOUS"
curl -i -X POST \
  https://docs.nelnetpay.com/_mock/apis/osi-payments-api/payments \
  -H 'Authorization: Bearer <YOUR_JWT_HERE>' \
  -H 'Content-Type: application/json' \
  -H 'nps-trace-uuid: string' \
  -d '{
    "entityId": 1325691045,
    "paymentType": {
      "ach": {
        "bankAccount": {
          "accountNumber": "459887746321Z",
          "routingNumber": "021000021",
          "accountType": "CHECKING"
        }
      }
    },
    "transactionType": "ACH_DEBIT",
    "amount": 123.65,
    "accountHolder": {
      "accountHolderName": "John Smith",
      "accountHolderId": "134267"
    },
    "transactionInformation": {
      "customId": "330d4c38-7904-47cf-be8e-0972a93f7386",
      "description": "tuition",
      "additionalPaymentInformation": "U00102",
      "companyName": "College Prep",
      "companyDiscretionaryData": "Test1234",
      "standardEntryCode": "WEB",
      "terminalCity": "MPLS",
      "terminalState": "MN",
      "discretionaryData": "R",
      "effectiveEntryDate": "250110",
      "originalTransactionType": "",
      "originalPaymentTransactionId": "80503dc9-15f8-430a-8622-3cff38124bbd"
    },
    "riskId": "12e3cdac-d347-4564-ba1f-305e5e1e8ded"
  }'

Responses

OK

Bodyapplication/json
responseCodestring[ 4 .. 5 ] characters

Response code defined by NPS indicating status of request.

Format Type: Alphanumeric

Length: 4 to 5

Example: "A100"
responseMessagestring

The text description of the response code.

Example: "Approved"
paymentTransactionIdstring= 36 characters

Unique transaction identifier. This value is used when sending a subsequent transaction such as a Capture or Refund.

Format Type: UUID

Length: 36

Example: "80503dc9-15f8-430a-8622-3cff38124bbd"
paymentTypeobject
accountValidationResultobject
processorResponseobject
riskResponseobject
Response
application/json
{
  "responseCode": "A100",
  "responseMessage": "Approved",
  "paymentTransactionId": "80503dc9-15f8-430a-8622-3cff38124bbd",
  "paymentType": {
    "ach": { … },
    "creditCard": { … },
    "applePay": { … }
  },
  "accountValidationResult": {
    "responseCode": "1",
    "thirdPartyResponseCode": "2",
    "bankName": "UB Bank"
  },
  "processorResponse": {
    "responseCode": "A0000",
    "responseMessage": "Success",
    "authorizationCode": "TAS890",
    "avsResultCode": "Z",
    "cvvResultCode": "M",
    "processedAmount": 123.65,
    "processorTransactionId": "49510555",
    "processorTransactionType": "Sale"
  },
  "riskResponse": {
    "responseCode": "0",
    "riskId": "12e3cdac-d347-4564-ba1f-305e5e1e8ded",
    "data": { … }
  }
}