> ## Documentation Index
> Fetch the complete documentation index at: https://docs.casexchange.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Jurisdictions & Counties

> Reference data for state, territory, and county coverage

## Overview

Jurisdictions represent the US states and territories supported by CaseXchange. Each jurisdiction has a two-letter `code` and a display `name`. Counties are a related resource — every county belongs to exactly one jurisdiction and can be fetched independently or filtered by jurisdiction code.

Both endpoints require the `read_only` API key tier and authenticate via the `X-API-Key` header.

## Endpoints

| Method | Path             | Description                                           |
| ------ | ---------------- | ----------------------------------------------------- |
| `GET`  | `/jurisdictions` | Returns all supported jurisdictions                   |
| `GET`  | `/counties`      | Returns counties, optionally filtered by jurisdiction |

## List jurisdictions

Returns an array of `{ code, name }` objects for every supported US state and territory.

```bash theme={null}
curl "https://api.casexchange.com/api/public/v1/jurisdictions" \
  -H "X-API-Key: cxp_ro_your_key_here"
```

Example response:

```json theme={null}
{
  "data": [
    { "code": "AL", "name": "Alabama" },
    { "code": "AK", "name": "Alaska" },
    { "code": "CA", "name": "California" },
    { "code": "FL", "name": "Florida" },
    { "code": "NJ", "name": "New Jersey" },
    { "code": "NY", "name": "New York" },
    { "code": "TX", "name": "Texas" }
  ],
  "meta": {
    "requestId": "req_8a4c2e1b9d3f5071a6c8e4d2",
    "timestamp": "2026-03-31T14:22:45.000Z"
  }
}
```

Use the two-letter `code` value when filtering counties or setting the jurisdiction on a case.

## List counties

Returns counties, optionally filtered by one or more jurisdiction codes via the `jurisdictionCodes` query parameter.

**Query parameters**

| Parameter           | Type   | Required | Description                                                                     |
| ------------------- | ------ | -------- | ------------------------------------------------------------------------------- |
| `jurisdictionCodes` | string | No       | Comma-separated jurisdiction codes (e.g. `NY,NJ`). Omit to return all counties. |

```bash theme={null}
curl "https://api.casexchange.com/api/public/v1/counties?jurisdictionCodes=NY,NJ" \
  -H "X-API-Key: cxp_ro_your_key_here"
```

Example response:

```json theme={null}
{
  "data": [
    {
      "id": "e5f6a7b8-9abc-def0-1234-567890abcdef",
      "name": "Kings County",
      "jurisdictionCode": "NY"
    },
    {
      "id": "f6a7b8c9-abcd-ef01-2345-67890abcdef0",
      "name": "New York County",
      "jurisdictionCode": "NY"
    },
    {
      "id": "b8c9d0e1-cdef-0123-4567-890abcdef012",
      "name": "Bergen County",
      "jurisdictionCode": "NJ"
    }
  ],
  "meta": {
    "requestId": "req_1b3d5f7a9c2e4068b0d2f4a6",
    "timestamp": "2026-03-31T14:23:12.000Z"
  }
}
```

Without `jurisdictionCodes` the response includes every county across all jurisdictions. Filter to keep payloads small when you only need specific states.

## Use cases

* Power jurisdiction and county dropdowns when creating or filtering cases.
* Validate inputs client-side before calling `POST /sent-cases`.
* Combine with firm specialties to narrow destination firms by region.
* Use the counties endpoint to build a two-step picker: select a jurisdiction first, then load its counties.

<Note>
  Jurisdiction codes follow standard postal abbreviations. Use uppercase strings in requests.
</Note>

## Related

* [Reference Data examples](/api-reference/examples/reference-data) — full curl examples for jurisdictions, counties, and case types.