# Retrieve the state cost effective for a product in a state on a given date

Endpoint: GET /v1/{countryCode}/products/{productNumber}/state-costs/{stateCode}/effective-cost
Version: 0.0.1
Security: jwt-authorizer

## Path parameters:

  - `countryCode` (string, required)
    Enum: "au", "nz"

  - `productNumber` (string, required)

  - `stateCode` (string, required)

## Query parameters:

  - `effectiveDate` (string, required)
    The date on which the returned cost takes effect, in ISO 8601 date format (YYYY-MM-DD).
    Example: "2026-07-01"

## Response 200 fields (application/json):

  - `productNumber` (string, required)
    The unique product number identifier.
    Example: "3000650"

  - `stateCode` (string, required)
    The two-character state code the cost applies to.
    Example: "03"

  - `effectiveDate` (string, required)
    The date on which the effective state cost takes effect (ISO 8601).
    Example: "2026-07-01"

  - `previous` (object, required)
    The state cost that applied immediately prior to the effective date.

  - `previous.fullyRebatedCost` (number, required)
    The fully rebated cost for the state.
    Example: 417.76

  - `previous.invoiceCost` (number, required)
    The state invoice cost.
    Example: 430.76

  - `previous.buyingGuideRecordNumber` (integer, required)
    Buying guide record number associated with the state cost.
    Example: 1198140

  - `effective` (object, required)
    The state cost taking effect on the effective date.

  - `effective.fullyRebatedCost` (number, required)
    The fully rebated cost for the state.
    Example: 417.76

  - `effective.invoiceCost` (number, required)
    The state invoice cost.
    Example: 430.76

  - `effective.buyingGuideRecordNumber` (integer, required)
    Buying guide record number associated with the state cost.
    Example: 1198140

## Response 400 fields (application/json):

  - `errorCode` (string, required)
    Stable, machine-readable application error identifier.
    Example: "RESOURCE_NOT_FOUND"

  - `message` (string, required)
    Human-readable description of the error.
    Example: "The requested resource was not found."

  - `status` (integer)
    HTTP status code.
    Example: 404

  - `timestamp` (string)
    Time the error occurred, in ISO 8601 format.
    Example: "2026-06-03T10:15:30Z"

  - `details` (array, required)
    Structured additional information, such as per-field validation errors.

  - `details.field` (string)
    The request field the issue relates to.
    Example: "stateCode"

  - `details.issue` (string)
    Description of the problem with the field.
    Example: "Must be a two-digit state code."

## Response 401 fields (application/json):

  - `errorCode` (string, required)
    Stable, machine-readable application error identifier.
    Example: "RESOURCE_NOT_FOUND"

  - `message` (string, required)
    Human-readable description of the error.
    Example: "The requested resource was not found."

  - `status` (integer)
    HTTP status code.
    Example: 404

  - `timestamp` (string)
    Time the error occurred, in ISO 8601 format.
    Example: "2026-06-03T10:15:30Z"

  - `details` (array)
    Structured additional information, such as per-field validation errors.