FastFlowPe is a payment orchestration platform. This documentation covers integration of our unified API for payments and payouts, SDKs, and workflows

curl --location 'https://api.fastflowpe.com/merchant/recurring/subscription/initialize' \
  --header 'Content-Type: application/json' \
  --header 'Accept: application/json' \
  --header 'x-api-key: YOUR_MERCHANT_X_API_KEY' \
  --data-raw '{
    "customer_info": {
      "merchant_ref_id": "SUB-MUKTE217-UNIQUE-001",
      "name": "Sabyasachi Biswal",
      "email": "sabyasachi@bluswap.co",
      "phone": "9521680514",
      "payment_mode": "UPI_RECURRING",
      "upi_id": "9521680514@ptsbi",
      "authorization_amount": 2
    },
    "plan_details": {
      "plan_name": "sabyatest",
      "plan_type": "PERIODIC",
      "plan_amount": 100,
      "plan_max_amount": 100,
      "plan_max_cycles": 6,
      "plan_intervals": 1,
      "plan_interval_type": "DAILY"
    },
    "subscription_meta": {
      "subscription_first_charge_time": "2026-10-07T00:00:00+05:30"
    }
  }'

{
  "status": "success",
  "status_code": 200,
  "message": "Subscription created. Redirect customer to complete mandate authorization.",
  "detail": null,
  "data": {
    "subscription_id": "YOUR_INTERNAL_SUBSCRIPTION_UUID",
    "merchant_ref_id": "SUB-MUKTE217-UNIQUE-001",
    "auth_data": {
      "url": "https://payments.cashfree.com/subscriptions/checkout/timer",
      "method": "post",
      "payload": {
        "paymentType": "UPI",
        "upiIntentData": {
          "iosAuthAppLinks": {
            "BHIM": "bhim://...",
            "GPAY": "tez://...",
            "PHONEPE": "phonepe://..."
          },
          "androidAuthAppLinks": {
            "BHIM": "bhim://...",
            "GPAY": "gpay://...",
            "PHONEPE": "phonepe://...",
            "DEFAULT": "upi://..."
          }
        }
      },
      "content_type": "application/json"
    }
  },
  "meta": null
}

{
  "status": "failure",
  "status_code": 400,
  "message": "Subscription creation failed",
  "detail": null,
  "data": {
    "subscription_id": "INTERNAL_SUBSCRIPTION_ID",
    "error_message": "Error returned by PSP",
    "raw_response": {}
  },
  "meta": null
}

Use the API key in the x-api-key header. Do not send it in the Authorization header, and cookies are not required.

Quick ReferenceRequired: Customer information, plan details, and first charge timeReturns: subscription_id, merchant_ref_id, auth_dataPayment Mode: UPI_RECURRING

Endpoint Details

Field	Value
Method	`POST`
Payload	`JSON`
URL	`https://api.fastflowpe.com/merchant/recurring/subscription/initialize`

Request Headers

string

required

Your secret API key issued by FastFlowPe.

string

required

Must be application/json.

string

required

Must be application/json.

Request Body

Customer Information

string

required

Your unique reference ID for the subscription. This value must not have been used previously.

string

required

Customer’s full name.

string

required

Customer’s email address.

string

required

Customer’s phone number.

string

required

Payment mode used for the subscription. For recurring UPI mandates, use UPI_RECURRING.

string

required

Customer’s UPI ID or VPA used to authorize the recurring mandate.

float

required

Amount authorized while setting up the mandate. It cannot exceed plan_amount.

Plan Details

string

required

Display name of the subscription plan.

string

required

Type of subscription plan.Supported values:

PERIODIC — charges are scheduled automatically based on the configured interval.
ON_DEMAND — charges can be initiated when required.

float

required

Amount charged during each billing cycle.

float

required

Maximum amount permitted for a charge under this subscription. It must be greater than or equal to plan_amount.

integer

required

Maximum number of billing cycles allowed for the subscription.

integer

required

Number of interval units between recurring charges.

string

required

Interval unit used for recurring charges.Supported values:

DAILY
WEEKLY
MONTHLY
YEARLY

For example, plan_intervals: 1 with plan_interval_type: DAILY means the subscription is charged once every day.

Subscription Metadata

string

required

First scheduled charge time in ISO 8601 format.Example: 2026-10-07T00:00:00+05:30

subscription_expiry_time is calculated automatically by FastFlowPe.Authorization details are also created internally using customer_info.authorization_amount.

Request Example

curl --location 'https://api.fastflowpe.com/merchant/recurring/subscription/initialize' \
  --header 'Content-Type: application/json' \
  --header 'Accept: application/json' \
  --header 'x-api-key: YOUR_MERCHANT_X_API_KEY' \
  --data-raw '{
    "customer_info": {
      "merchant_ref_id": "SUB-MUKTE217-UNIQUE-001",
      "name": "Sabyasachi Biswal",
      "email": "sabyasachi@bluswap.co",
      "phone": "9521680514",
      "payment_mode": "UPI_RECURRING",
      "upi_id": "9521680514@ptsbi",
      "authorization_amount": 2
    },
    "plan_details": {
      "plan_name": "sabyatest",
      "plan_type": "PERIODIC",
      "plan_amount": 100,
      "plan_max_amount": 100,
      "plan_max_cycles": 6,
      "plan_intervals": 1,
      "plan_interval_type": "DAILY"
    },
    "subscription_meta": {
      "subscription_first_charge_time": "2026-10-07T00:00:00+05:30"
    }
  }'

Response

A successful request returns a 200 response with the FastFlowPe subscription ID, merchant reference ID, and authorization information required to complete the mandate. If subscription creation fails, the API returns a failure response with the internal subscription ID and the error received while creating the subscription.

{
  "status": "success",
  "status_code": 200,
  "message": "Subscription created. Redirect customer to complete mandate authorization.",
  "detail": null,
  "data": {
    "subscription_id": "YOUR_INTERNAL_SUBSCRIPTION_UUID",
    "merchant_ref_id": "SUB-MUKTE217-UNIQUE-001",
    "auth_data": {
      "url": "https://payments.cashfree.com/subscriptions/checkout/timer",
      "method": "post",
      "payload": {
        "paymentType": "UPI",
        "upiIntentData": {
          "iosAuthAppLinks": {
            "BHIM": "bhim://...",
            "GPAY": "tez://...",
            "PHONEPE": "phonepe://..."
          },
          "androidAuthAppLinks": {
            "BHIM": "bhim://...",
            "GPAY": "gpay://...",
            "PHONEPE": "phonepe://...",
            "DEFAULT": "upi://..."
          }
        }
      },
      "content_type": "application/json"
    }
  },
  "meta": null
}

{
  "status": "failure",
  "status_code": 400,
  "message": "Subscription creation failed",
  "detail": null,
  "data": {
    "subscription_id": "INTERNAL_SUBSCRIPTION_ID",
    "error_message": "Error returned by PSP",
    "raw_response": {}
  },
  "meta": null
}

Response Fields

string

Indicates whether the subscription initialization request succeeded or failed.Possible values include success and failure.

integer

HTTP-style status code associated with the response.A successful request returns 200. Validation or subscription creation failures may return a 4xx status code.

string

Human-readable message describing the result of the request.

object

Additional details related to the response when available.This may be null.

string

Unique FastFlowPe internal subscription ID.This value may be returned for both successful and failed subscription creation attempts.

string

Merchant reference ID originally provided in customer_info.merchant_ref_id.This field is returned when the subscription is created successfully.

object

Authorization information required for the customer to complete the recurring mandate setup.This field is returned when subscription initialization succeeds.

string

URL associated with the mandate authorization flow.

string

HTTP method associated with the authorization request.Typically returned as post.

object

Payment authorization payload containing the details needed to complete mandate authorization.

string

Payment type used for mandate authorization.For UPI recurring subscriptions, this is UPI.

object

Contains platform-specific UPI application links that can be used to complete the mandate authorization.

object

UPI application deep links returned for supported iOS applications such as BHIM, Google Pay, and PhonePe.

object

UPI application deep links returned for supported Android applications.A generic DEFAULT UPI deep link may also be returned.

string

Content type associated with the authorization payload.Typically application/json.

string

Error message returned when the subscription could not be created.This field is present in failure responses.

object

Raw error response received while attempting to create the subscription.This field can be used for debugging or support investigation.

object

Optional response metadata.This may be null.

A successful subscription initialization does not mean that the recurring mandate has already been authorized.The customer must complete the mandate authorization using the details returned in auth_data.

If subscription creation fails, an internal subscription_id may still be returned.Use error_message and raw_response to understand the reason for the failure.

Store both subscription_id and merchant_ref_id for successful subscriptions. Use subscription_id for FastFlowPe subscription operations and merchant_ref_id to correlate the subscription with your own records.

curl --location 'https://api.fastflowpe.com/merchant/recurring/subscription/initialize' \
  --header 'Content-Type: application/json' \
  --header 'Accept: application/json' \
  --header 'x-api-key: YOUR_MERCHANT_X_API_KEY' \
  --data-raw '{
    "customer_info": {
      "merchant_ref_id": "SUB-MUKTE217-UNIQUE-001",
      "name": "Sabyasachi Biswal",
      "email": "sabyasachi@bluswap.co",
      "phone": "9521680514",
      "payment_mode": "UPI_RECURRING",
      "upi_id": "9521680514@ptsbi",
      "authorization_amount": 2
    },
    "plan_details": {
      "plan_name": "sabyatest",
      "plan_type": "PERIODIC",
      "plan_amount": 100,
      "plan_max_amount": 100,
      "plan_max_cycles": 6,
      "plan_intervals": 1,
      "plan_interval_type": "DAILY"
    },
    "subscription_meta": {
      "subscription_first_charge_time": "2026-10-07T00:00:00+05:30"
    }
  }'

{
  "status": "success",
  "status_code": 200,
  "message": "Subscription created. Redirect customer to complete mandate authorization.",
  "detail": null,
  "data": {
    "subscription_id": "YOUR_INTERNAL_SUBSCRIPTION_UUID",
    "merchant_ref_id": "SUB-MUKTE217-UNIQUE-001",
    "auth_data": {
      "url": "https://payments.cashfree.com/subscriptions/checkout/timer",
      "method": "post",
      "payload": {
        "paymentType": "UPI",
        "upiIntentData": {
          "iosAuthAppLinks": {
            "BHIM": "bhim://...",
            "GPAY": "tez://...",
            "PHONEPE": "phonepe://..."
          },
          "androidAuthAppLinks": {
            "BHIM": "bhim://...",
            "GPAY": "gpay://...",
            "PHONEPE": "phonepe://...",
            "DEFAULT": "upi://..."
          }
        }
      },
      "content_type": "application/json"
    }
  },
  "meta": null
}

{
  "status": "failure",
  "status_code": 400,
  "message": "Subscription creation failed",
  "detail": null,
  "data": {
    "subscription_id": "INTERNAL_SUBSCRIPTION_ID",
    "error_message": "Error returned by PSP",
    "raw_response": {}
  },
  "meta": null
}

Get Started

Collections

Payment Links

Fund Transfer

Refunds

Callbacks

subscription

Initiate Subscription

Endpoint Details

Request Headers

Request Body

Customer Information

Plan Details

Subscription Metadata

Request Example

Response

Response Fields

​Endpoint Details

​Request Headers

​Request Body

​Customer Information

​Plan Details

​Subscription Metadata

​Request Example

​Response

​Response Fields

Endpoint Details

Request Headers

Request Body

Customer Information

Plan Details

Subscription Metadata

Request Example

Response

Response Fields