---
title: "Create Tax Association"
method: POST
path: "/taxes/associations"
tags: ["Tax Associations"]
---

# Create Tax Association

`POST /taxes/associations`

Use when linking a tax rate to an entity (e.g. customer, product, or region) so that rate applies on invoices.

## Request body

- CreateTaxAssociationRequest
  - `auto_apply` boolean
  - `currency` string
  - `end_date` string, date-time — EndDate sets when this association expires. Must be after StartDate when both are provided.
  - `entity_id` string
  - `entity_type` 'customer' | 'subscription' | 'invoice' | 'tenant'
  - `external_customer_id` string
  - `metadata` object
  - `priority` integer
  - `start_date` string, date-time — StartDate sets when this association becomes active. Defaults to now if omitted.
  - `tax_behavior` 'inclusive' | 'exclusive'
  - `tax_rate_code` string, required

## Response `200`

OK

- TaxAssociationResponse
  - `auto_apply` boolean — Whether this tax should be automatically applied
  - `created_at` string, date-time
  - `created_by` string
  - `currency` string — Currency
  - `end_date` string, date-time — EndDate is the optional date until which this association is active
  - `entity_id` string — ID of the entity this tax rate applies to
  - `entity_type` 'customer' | 'subscription' | 'invoice' | 'tenant'
  - `environment_id` string — EnvironmentID is the ID of the environment this tax rate config belongs to
  - `id` string — ID of the ent.
  - `metadata` object — Metadata holds the value of the "metadata" field.
  - `priority` integer — Priority for tax resolution (lower number = higher priority)
  - `start_date` string, date-time — StartDate is the date from which this association is active
  - `status` 'published' | 'deleted' | 'archived'
  - `tax_behavior` 'inclusive' | 'exclusive'
  - `tax_rate` TaxRateResponse
    - `code` string
    - `created_at` string, date-time
    - `created_by` string
    - `description` string
    - `environment_id` string
    - `id` string
    - `metadata` object
    - `name` string
    - `percentage_value` string
    - `scope` 'INTERNAL' | 'EXTERNAL' | 'ONETIME'
    - `status` 'published' | 'deleted' | 'archived'
    - `tax_rate_status` 'ACTIVE' | 'INACTIVE'
    - `tax_rate_type` 'percentage'
    - `tenant_id` string
    - `updated_at` string, date-time
    - `updated_by` string
  - `tax_rate_id` string — Reference to the TaxRate entity
  - `tenant_id` string
  - `updated_at` string, date-time
  - `updated_by` string

## Other responses

- `400` — Invalid request
- `500` — Server error

## Changes

- **2026-09-01** `e1d4e27b5677` — 1 warning, 3 info
  - removed the optional property `tax_rate/fixed_value` from the response with the `200` status
  - added the new optional request property `tax_behavior`
  - added the optional property `tax_behavior` to the response with the `200` status
  - removed the `fixed` enum value from the `tax_rate/tax_rate_type` response property for the response status `200`
- **2026-07-15** `f8ecf435d25d` — 2 warning
  - added the new `not_implemented` enum value to the `code` response property for the response status `400`
  - added the new `not_implemented` enum value to the `code` response property for the response status `500`
- **2026-07-09** `646d6658479b` — 2 breaking
  - the `end_date` request property type/format changed from `string`/`` to `string`/`date-time`
  - the `start_date` request property type/format changed from `string`/`` to `string`/`date-time`
- **2026-07-09** `7d57386313c7` — 8 breaking, 17 warning, 4 info
  - request property `entity_type` was restricted to a list of enum values
  - the `entity_type` request property type/format changed from ``/`` to `string`/``
  - the `entity_type` response's property type/format changed from ``/`` to `string`/`` for status `200`
  - the `status` response's property type/format changed from ``/`` to `string`/`` for status `200`
  - …25 more
- …earlier changes not shown

[Full history](https://skmtc.dev/flexprice/apis/flexprice-api/changes/taxes/associations/post.md)

---

[API](https://skmtc.dev/flexprice/apis/flexprice-api.md) · [All operations](https://skmtc.dev/flexprice/apis/flexprice-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/flexprice/flexprice-api/revisions/fd7112159d0a/schema)