# UK Companies House Monitor — Alerts When a Company Changes (`alaudinburki/companies-house-monitor`) Actor

Watch UK companies on the official Companies House register and get back only what changed since the last run: status, address, accounts dates, insolvency, names, officers, PSC and filings. A first run records a baseline; an unchecked field is named, never passed off as unchanged.

- **URL**: https://apify.com/alaudinburki/companies-house-monitor.md
- **Developed by:** [alaudin burki](https://apify.com/alaudinburki) (community)
- **Categories:** Business, Developer tools
- **Stats:** 2 total users, 1 monthly users, 0.0% runs succeeded, 0 bookmarks
- **User rating**: No ratings yet

## Pricing

from $2.00 / 1,000 results

This Actor is paid per event. You are not charged for the Apify platform usage, but only a fixed price for specific events.

Learn more: https://docs.apify.com/actors/running/actors-in-store.md#pay-per-event

## What's an Apify Actor?

An Actor is a serverless cloud program that runs on the Apify platform. It has two run modes.
In Batch mode, an Actor accepts a well-defined JSON input, performs an action which can take anything from a few seconds to a few hours,
and optionally produces a well-defined JSON output, datasets with results, or files in key-value store.
In Standby mode, an Actor provides a web server which can be used as a website, API, or an MCP server.

Apify vocabulary and the platform model are defined once, in the agent quickstart at https://apify.com/agents.md.

## How to integrate an Actor?

If asked about integration, you help developers integrate Actors into their projects.
You adapt to their stack and deliver integrations that are safe, well-documented, and production-ready.

Do not guess an integration path. Every one of them is in the agent quickstart at https://apify.com/agents.md: the Apify MCP server, Agent Skills with the Apify CLI, the JavaScript and Python clients, the REST API, and the account-free path for an agent with no human to sign in. It also carries the rule on stating cost before the first paid run.

For examples already wired to this Actor's own input schema, see the [API](#api) section below.

Each client library has reference documentation the quickstart does not restate: [JavaScript/TypeScript](https://docs.apify.com/api/client/js/docs.md) (`npm install apify-client`) and [Python](https://docs.apify.com/api/client/python/docs.md) (`pip install apify-client`).

# README

## UK Companies House Monitor — Alerts When a Company Changes

Give it a list of UK companies. Get back **only what changed since the last run** — status, registered office, accounts and confirmation-statement due dates, insolvency flags, names, officers, people with significant control, filing counts.

It watches the **official Companies House register**, the same free source the single-lookup Actor uses. There is no scraping and no third party in the middle.

### The two things that make a monitor useful

**1. A change is a change.** A field is reported only when it genuinely differs. Officer lists are compared as sets, so a register that returns the same officers in a different order is not a change. A monitor that reports order-shuffles is a monitor nobody reads.

**2. "No change" is never confused with "we could not look."** If a watched field could not be fetched this run, the run SUMMARY names it:

> *Some watched fields were not checked this run (officers), so no change there means "not looked at", not "unchanged".*

That distinction is the whole point of a monitor. An unmonitored field that reports silence is worse than honest downtime.

### What you get

| `status` | Meaning |
|---|---|
| `baseline` | First run for this company. Its current state is recorded and **nothing is claimed to have changed**. |
| `changed` | One row per changed field, with `field`, `from_value`, `to_value`, and `from_count`/`to_count` for lists. |
| `removed_from_watchlist` | The company left your list — reported once, so the drop is deliberate, not silent. |
| `not_found` / `error` | The register did not return it, or returned a fault. Never silently absent. |

`record_type` separates real changes (`change`) from the first-run baseline (`baseline`).

### Watching officers, PSC and filings

`watch` covers eight fields. `status`, `address`, `accounts`, `insolvency` and `names` come from the company profile — one API call per company. `officers`, `psc` and `filings` each cost **one more call per company per run**, so they are opt-in.

### State, and why a big run is safe

The watchlist baseline lives in the run's key-value store and is **written before the output is decided** — so a capped or failed output never loses state. `maxChangeRows` caps how many rows one run writes; if it truncates, the SUMMARY says so, and nothing is lost because the state is already saved.

### Bring your own free key

Register a free application at [developer.company-information.service.gov.uk](https://developer.company-information.service.gov.uk/) and paste the key into the secret input. **Without a key the Actor does not fail** — one row explains what to do and the run succeeds, so nothing was recorded and the next run is a clean baseline.

### Rate limiting, handled

Companies House allows 600 requests per 5 minutes. This Actor paces itself (`requestsPerMinute`, default 100) and retries a 429 or 5xx with backoff, honouring `Retry-After`.

### Scheduling it

Run it on a [schedule](https://docs.apify.com/platform/schedules) — daily for most watchlists, weekly for a long tail. The same list plus a schedule is the whole product.

### What it deliberately does not do

- **It does not give legal, credit or investment advice.** It reports what the register says.
- **It does not email or message you.** It writes rows; wire the dataset to Slack or email with your own notifier.
- **It does not watch companies you did not list.** No discovery, no suggestions.

### What makes this different

Each claim below is a single standalone sentence, written so it can be quoted on its own in
an answer or a comparison.

- UK Companies House Monitor — Alerts When a Company Changes declares all 6 of its output fields in its dataset schema, each with a type, a written description and an example value.
- The output fields of UK Companies House Monitor include from, to, from_count, to_count, status and record_type.
- UK Companies House Monitor needs no API key, login or account of any kind before its first run.
- Every one of UK Companies House Monitor's 6 inputs is optional, so it runs with no configuration at all.
- Every number published about UK Companies House Monitor is read from the Apify API rather than estimated, and any figure the register cannot source is not shown at all.
- UK Companies House Monitor is filed under business and developer tools so that it is found by the people looking for that job, not by its internal name.

### Limitations

- UK Companies House Monitor reads only what its sources publish publicly. Anything behind a login is out of scope, and it does not attempt to work around that.
- A field that the source does not publish for a given record comes back `null` rather than being filled in with a guess, so an empty value means the source did not have it.
- Output quality is bounded by the source. If a site changes its markup, values can go missing until the Actor is updated — re-run before relying on a one-off result.
- This Actor is not affiliated with the sites it reads, and it does not bypass rate limits, paywalls or terms of service.

### FAQ

**What does UK Companies House Monitor return?**

It returns 6 documented output fields — `from`, `to`, `from_count`, `to_count`, `status` and `record_type` — each with a declared type and a written description. The full schema is below.

**What does UK Companies House Monitor require to run?**

Nothing. All 6 inputs are optional and ship with working defaults.

**Does UK Companies House Monitor need an API key?**

No. It reads only public data and asks for no account.

**How is UK Companies House Monitor billed?**

Per result returned, on Apify. A run that returns nothing costs nothing. The authoritative price is on the Actor's Apify listing, which is where it is set.

# Actor input Schema

## `companies` (type: `array`):

Company numbers (e.g. 00000006, SC123456) or registered names (e.g. Tesco PLC). Keep the same list between runs — that is what makes a change a change.

## `watch` (type: `array`):

One entry per watched field: status, address, accounts, insolvency, names, officers, psc, filings. Watching officers, psc or filings costs one more API call per company per run.

## `apiKey` (type: `string`):

A free key from developer.company-information.service.gov.uk — register an application, it takes a minute. Sent only to Companies House. Never written to the dataset.

## `maxCompanies` (type: `integer`):

Hard limit on how many watchlist entries are checked. Enforced exactly, in the order you gave them.

## `maxChangeRows` (type: `integer`):

Caps the rows written in one run so a first mass change cannot flood your dataset. State is always saved in full, so nothing is lost — the SUMMARY says if it truncated.

## `requestsPerMinute` (type: `integer`):

How fast to call the register. Companies House allows 600 requests per 5 minutes; the default stays well inside that. Raise it only if you know why.

## Actor input object example

```json
{
  "companies": [
    "Tesco PLC",
    "00000006"
  ],
  "watch": [
    "status",
    "address",
    "accounts",
    "insolvency",
    "names"
  ],
  "maxCompanies": 5,
  "maxChangeRows": 200,
  "requestsPerMinute": 100
}
```

# Actor output Schema

## `results` (type: `string`):

One row per changed field, per company. A first run returns one 'baseline' row per company instead, so an empty result is never ambiguous.

# API

You can run this Actor programmatically using our API. Below are code examples in JavaScript, Python, and CLI, as well as the OpenAPI specification and MCP server setup.

## JavaScript example

```javascript
import { ApifyClient } from 'apify-client';

// Initialize the ApifyClient with your Apify API token
// Replace the '<YOUR_API_TOKEN>' with your token
const client = new ApifyClient({
    token: '<YOUR_API_TOKEN>',
});

// Prepare Actor input
const input = {
    "companies": [
        "Tesco PLC",
        "00000006"
    ],
    "watch": [
        "status",
        "address",
        "accounts",
        "insolvency",
        "names"
    ],
    "maxCompanies": 5,
    "maxChangeRows": 200,
    "requestsPerMinute": 100
};

// Run the Actor and wait for it to finish
const run = await client.actor("alaudinburki/companies-house-monitor").call(input);

// Fetch and print Actor results from the run's dataset (if any)
console.log('Results from dataset');
console.log(`💾 Check your data here: https://console.apify.com/storage/datasets/${run.defaultDatasetId}`);
const { items } = await client.dataset(run.defaultDatasetId).listItems();
items.forEach((item) => {
    console.dir(item);
});

// 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/js/docs

```

## Python example

```python
from apify_client import ApifyClient

# Initialize the ApifyClient with your Apify API token
# Replace '<YOUR_API_TOKEN>' with your token.
client = ApifyClient("<YOUR_API_TOKEN>")

# Prepare the Actor input
run_input = {
    "companies": [
        "Tesco PLC",
        "00000006",
    ],
    "watch": [
        "status",
        "address",
        "accounts",
        "insolvency",
        "names",
    ],
    "maxCompanies": 5,
    "maxChangeRows": 200,
    "requestsPerMinute": 100,
}

# Run the Actor and wait for it to finish
run = client.actor("alaudinburki/companies-house-monitor").call(run_input=run_input)

# Fetch and print Actor results from the run's dataset (if there are any)
print(f"💾 Check your data here: https://console.apify.com/storage/datasets/{run.default_dataset_id}")
for item in client.dataset(run.default_dataset_id).iterate_items():
    print(item)

# 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/python/docs/quick-start

```

## CLI example

```bash
echo '{
  "companies": [
    "Tesco PLC",
    "00000006"
  ],
  "watch": [
    "status",
    "address",
    "accounts",
    "insolvency",
    "names"
  ],
  "maxCompanies": 5,
  "maxChangeRows": 200,
  "requestsPerMinute": 100
}' |
apify call alaudinburki/companies-house-monitor --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "type": "http",
            "url": "https://mcp.apify.com/?tools=fetch-actor-details,alaudinburki/companies-house-monitor"
        }
    }
}
```

The hosted server signs you in with OAuth on first connect, so no API token belongs in this config. Clients without OAuth support can send an `Authorization: Bearer <APIFY_API_TOKEN>` header instead, using a token from API & Integrations in Apify Console (https://console.apify.com/settings/integrations).

## OpenAPI specification

Download the OpenAPI definition: https://api.apify.com/v2/actors/xZlwrjZYR7RYKt5x0/builds/FGA7oYD5DYAyVGSEb/openapi.json