---
title: "Create a Payment Instrument Association"
method: POST
path: "/payment_instrument_associations"
tags: ["Payment Instrument Associations"]
---

# Create a Payment Instrument Association

`POST /payment_instrument_associations`

Create a `Payment Instrument Association` to associate a `Payment Instrument` with a `Merchant` for fee assignment purposes.

## Headers

- `Finix-Version` string
- `Content-Type` string

## Request body

- CreatePaymentInstrumentAssociation
  - `merchant_id` string, required — The ID of the `Merchant` that fees will be applied to.
  - `payment_instrument_id` string, required — The ID of the `Payment Instrument` whose events will be charged to the specified merchant.
  - `tags` Tags, nullable — Include up to 50 `key: value` pairs to annotate requests with custom metadata. - Maximum character length for individual `keys` is 40. - Maximum character length for individual `values` is 500. (For example, `order_number: 25`, `item_type: produce`, `department: sales`)

## Response `201`

A single Payment Instrument Association

- PaymentInstrumentAssociation
  - `id` string — The ID of the `Payment Instrument Association`.
  - `created_at` string, date-time — Timestamp of when the object was created.
  - `updated_at` string, date-time — Timestamp of when the object was last updated.
  - `application_id` string — The ID of the `Application` the resource was created under.
  - `enabled` boolean — Indicates whether this current `Payment Instrument Association` is enabled.
  - `payment_instrument_id` string — The ID of the `Payment Instrument` whose events will be charged to the specified merchant.
  - `merchant_id` string — The ID of the `Merchant` that fees will be applied to.
  - `tags` Tags, nullable — Include up to 50 `key: value` pairs to annotate requests with custom metadata. - Maximum character length for individual `keys` is 40. - Maximum character length for individual `values` is 500. (For example, `order_number: 25`, `item_type: produce`, `department: sales`)
  - `_links` object
    - `self` Self — Link to the resource that was used in the request.
      - `href` string

## Other responses

- `400` — Bad Request. The server cannot process the request due to malformed syntax or invalid data.
- `401` — Unauthorized. Authentication is required and has failed or has not been provided.
- `403` — Forbidden. The client is authenticated but does not have permission to access the resource.
- `404` — Not Found. The requested resource could not be found on the server.
- `406` — Not Acceptable. The server could not accept the submitted request. Confirm how the request was formatted and submitted.

---

[API](https://skmtc.net/finix/apis/finix-api-reference.md) · [All operations](https://skmtc.net/finix/apis/finix-api-reference/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/finix/finix-api-reference/revisions/96653f0c196b/schema)