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

# Company Matching API

> Match a company name to a UK Companies House registration number.

Send a company name (optionally with a website, postcode, address, SIC code, or trading date) and get back the best matching UK company registration number (CRN), plus the registered name, active status, and a confidence level.

> [!NOTE]
>
> **This API is in beta.** It is stable enough to build against and serves production data. Keys are
> issued by hand. Email [support@thedatacity.com](mailto:support@thedatacity.com) to get one.
> Feedback now shapes what ships next.

## What you get back

| Field | What it is |
| - | - |
| **matched\_company\_number** | Companies House registration number (CRN), when a match is found |
| **matched\_company\_name** | Registered name for that CRN |
| **matched\_registered\_postcode** | Registered office postcode for that CRN |
| **active** | Active / inactive (or equivalent) status from our company data |
| **confidence** | How strong the match is: `high`, `medium`, `low`, or `none` |
| **rigorous\_match** | Whether the match passed the stricter scoring check |
| **route** | Which matching path ran: `fast`, `local`, `slow`, or `null` when unmatched |
| **Request fields** | Your `input_name`, optional `id`, URL, postcode, address, SIC, and trading date |

Each result includes a confidence level, so you can decide how much to trust it. See the [response reference](https://docs.thedatacity.com/company-matching/guides/response-reference.md) for what every field contains.

A single `POST /match` returns one result. For lists, submit a batch and poll until it completes, or pass `callback_url` to be notified once.

## Who it's for

Use this API when you need to attach a reliable Companies House identity to customer lists, CRM records, or enrichment pipelines.

## How to get started

> [card] [Quickstart](https://docs.thedatacity.com/company-matching/guides/quickstart.md)
>
> Get an API key and match your first company in a few minutes.

> [card] [Authentication](https://docs.thedatacity.com/company-matching/guides/authentication.md)
>
> Customer API keys (`dm_live_…`) as a Bearer token.

> [card] [Response reference](https://docs.thedatacity.com/company-matching/guides/response-reference.md)
>
> Every field in the response, and when it is empty.

> [card] [Batch matching](https://docs.thedatacity.com/company-matching/guides/batch.md)
>
> Submit up to 1,000 companies and poll for results.

> [card] [Errors](https://docs.thedatacity.com/company-matching/guides/errors.md)
>
> Status codes, what they mean, and what to do.

> [card] [Rate limits](https://docs.thedatacity.com/company-matching/guides/rate-limits.md)
>
> Per-minute limits on match endpoints.

> [card] [Data handling](https://docs.thedatacity.com/company-matching/guides/data-handling.md)
>
> Where the data you submit goes, and how long we keep it.

> [card] [Versioning](https://docs.thedatacity.com/company-matching/guides/versioning.md)
>
> The `/api/v1` contract, the release number, and what counts as breaking.

> [card] [Changelog](https://docs.thedatacity.com/company-matching/changelog.md)
>
> Material changes to the API, newest first.

## Base URL

```text theme={null}
https://datamatcher-api.thedatacity.com/api/v1
```

All match endpoints sit under `/api/v1/match`. The interactive playground on each endpoint page lets you paste your API key and send live requests.

<Snippet file="need-help.mdx" />


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