PayFast Payment Form API

openapi: 3.1.0
info:
  title: PayFast Credit Card Transactions Payment Form API
  description: 'South African payment gateway providing REST APIs for online payment processing, subscription billing, tokenized recurring card payments, onsite checkout, and merchant refunds. Trusted by 80,000+ South African businesses and certified PCI-DSS Level 1.

    '
  version: v1
  contact:
    name: PayFast Developer Support
    url: https://support.payfast.help
  license:
    name: Proprietary
    url: https://payfast.io
servers:
- url: https://api.payfast.co.za/v1
  description: Production API server
- url: https://sandbox.payfast.co.za/v1
  description: Sandbox / test server
security:
- merchantAuth: []
tags:
- name: Payment Form
  description: Standard redirect-based payment form integration
paths:
  /eng/process:
    post:
      operationId: initiatePayment
      summary: Initiate a standard payment (form redirect)
      description: 'Standard payment form POST to initiate a PayFast redirect checkout. The customer is redirected to PayFast to complete payment. This endpoint is on the www.payfast.co.za (or sandbox.payfast.co.za) domain.

        '
      tags:
      - Payment Form
      servers:
      - url: https://www.payfast.co.za
        description: Production payment form
      - url: https://sandbox.payfast.co.za
        description: Sandbox payment form
      requestBody:
        required: true
        content:
          application/x-www-form-urlencoded:
            schema:
              $ref: '#/components/schemas/PaymentFormRequest'
      responses:
        '302':
          description: Redirects the customer to the PayFast payment page
components:
  schemas:
    PaymentFormRequest:
      type: object
      required:
      - merchant_id
      - merchant_key
      - amount
      - item_name
      - signature
      properties:
        merchant_id:
          type: string
          description: PayFast merchant ID
          example: '10000100'
        merchant_key:
          type: string
          description: PayFast merchant key
          example: 46f0cd694581a
        return_url:
          type: string
          format: uri
          description: URL to redirect to after successful payment
          example: https://www.example.com/return
        cancel_url:
          type: string
          format: uri
          description: URL to redirect to if customer cancels
          example: https://www.example.com/cancel
        notify_url:
          type: string
          format: uri
          description: ITN notification URL
          example: https://www.example.com/notify
        name_first:
          type: string
          description: Customer first name
          example: Jane
        name_last:
          type: string
          description: Customer last name
          example: Smith
        email_address:
          type: string
          format: email
          description: Customer email address
          example: jane@example.com
        cell_number:
          type: string
          description: Customer cell number
          example: '+27821234567'
        m_payment_id:
          type: string
          description: Merchant payment reference ID (up to 100 chars)
          maxLength: 100
          example: order-1234
        amount:
          type: string
          description: Payment amount formatted to 2 decimal places (ZAR)
          example: '99.00'
        item_name:
          type: string
          description: Name of item being purchased
          maxLength: 100
          example: Premium subscription
        item_description:
          type: string
          description: Description of item
          maxLength: 255
          example: Monthly premium plan
        custom_int1:
          type: integer
          description: Custom integer field 1
        custom_int2:
          type: integer
          description: Custom integer field 2
        custom_int3:
          type: integer
          description: Custom integer field 3
        custom_int4:
          type: integer
          description: Custom integer field 4
        custom_int5:
          type: integer
          description: Custom integer field 5
        custom_str1:
          type: string
          description: Custom string field 1
          maxLength: 255
        custom_str2:
          type: string
          description: Custom string field 2
          maxLength: 255
        custom_str3:
          type: string
          description: Custom string field 3
          maxLength: 255
        custom_str4:
          type: string
          description: Custom string field 4
          maxLength: 255
        custom_str5:
          type: string
          description: Custom string field 5
          maxLength: 255
        email_confirmation:
          type: integer
          description: Send confirmation email (1=yes)
          enum:
          - 0
          - 1
          example: 1
        confirmation_address:
          type: string
          format: email
          description: Email address for confirmation
          example: merchant@example.com
        currency:
          type: string
          description: Transaction currency (default ZAR)
          default: ZAR
          example: ZAR
        payment_method:
          type: string
          description: Restrict payment to a specific method (cc, dc, ef, etc.)
          example: cc
        subscription_type:
          type: integer
          description: Subscription type (1=recurring billing, 2=tokenization)
          enum:
          - 1
          - 2
          example: 1
        billing_date:
          type: string
          format: date
          description: First billing date for subscriptions (YYYY-MM-DD)
          example: '2026-07-01'
        recurring_amount:
          type: string
          description: Recurring billing amount (ZAR, 2 decimal places)
          example: '99.00'
        frequency:
          type: integer
          description: 'Billing frequency (3=monthly, 4=quarterly, 5=biannually, 6=annually)

            '
          enum:
          - 3
          - 4
          - 5
          - 6
          example: 3
        cycles:
          type: integer
          description: Number of billing cycles (0=indefinite)
          example: 12
        subscription_notify_email:
          type: integer
          description: Notify merchant of subscription updates via email (1=yes)
          enum:
          - 0
          - 1
          example: 1
        subscription_notify_webhook:
          type: integer
          description: Notify merchant of subscription updates via webhook (1=yes)
          enum:
          - 0
          - 1
          example: 1
        subscription_notify_buyer:
          type: integer
          description: Notify buyer of subscription updates (1=yes)
          enum:
          - 0
          - 1
          example: 1
        signature:
          type: string
          description: MD5 signature of the payment parameters
          example: ad3e6c84d5e5f374a3a0431bc5acbc90
  securitySchemes:
    merchantAuth:
      type: apiKey
      in: header
      name: merchant-id
      description: 'PayFast API authentication uses an MD5 signature derived from the merchant ID, passphrase, timestamp, and request data. Required headers include merchant-id, version, timestamp, and signature.

        '