Is the Companies House API really free?

Yes. The UK government provides it free as a public service. There is no paid tier — meaning the 600 requests / 5-minute rate limit is the hard ceiling.

Does Prometiam replace the Companies House API?

For UK-only low-volume use cases, no — and we would not recommend it. For multi-country (UK + EU) use cases, batch enrichment that exceeds the CH rate limit, or any workflow that needs sanctions screening in the same call, yes.

Where does Prometiam UK data come from?

From the official Companies House sources — bulk product files plus the daily delta feed, plus The Gazette for insolvency notices. Same data lineage as the CH API; Prometiam normalizes it into a multi-country schema and adds sanctions screening.

Can I use both the CH API and Prometiam together?

Yes. Common pattern: use CH for real-time filing-event consumption and Prometiam for batch enrichment, multi-country queries, and sanctions screening.

Does Prometiam cover Persons with Significant Control (PSC)?

Yes. PSC data for UK companies is embedded in /companies/{id} and /people/{id} responses, and the director-network graph at /directors/network exposes cross-company linkages.

How does pricing compare?

CH is free with a hard rate limit. Prometiam has a 14-day free trial (1,000 calls/month, no card, not an ongoing plan); paid starts at €9.99/mo for 10,000 calls/month (Starter), or €29.99/mo for 100,000 calls/month with full sanctions screening (Professional), with annual billing at ten months' price for twelve. The right comparison is "free CH + paid sanctions vendor + paid EU vendor" vs "Prometiam Professional at €29.99/mo".

Companies House API: rate limits, cost and access (2026)

An honest comparison between Prometiam and the UK Companies House public API. The CH API is the canonical, free, government-maintained source of truth for UK company data, and for UK-only use cases that fit inside its 600 requests / 5-minute rate limit, you should keep using it. Prometiam is the right alternative when you also need EU coverage, need sanctions screening in the same API, want normalized corporate events instead of raw filings, or exceed the CH rate limit.

Why teams look for an alternative

Multi-country need: as soon as a portfolio touches Spain or France, CH (UK-only by design) requires a second integration.
The 600 requests / 5-minute rate limit is hard for medium-volume workloads, and there is no paid tier to lift it.
No sanctions screening — CH tells you who is behind a UK company, not whether they are listed.
CH returns raw filings; you classify capital changes, director changes, and dissolutions yourself.

Where Prometiam adds value

Prometiam is a layer on top, not a re-hosted copy. Its UK data comes from the same official Companies House bulk product files plus the daily delta feed and The Gazette for insolvency notices. It adds further coverage on the same endpoints (Spain via BORME, France via BODACC, Norway via Brønnøysundregistrene with companies and directors, plus Ireland and Poland at company level only — no directors or UBO there), sanctions and US export-control screening across 6 sources (EU, UN, OFAC, UK OFSI, French gels, and the US Consolidated Screening List / BIS Entity List, Denied Persons, ITAR) covering 44,000+ active entities, and normalized typed corporate events. UK beneficial ownership is covered via PSC data. PEP screening is beta and Spain-only (no relatives or close associates); no adverse-media, and no natural-person identity verification.

Pricing and rate limits

CH is free with a hard ceiling. Prometiam has a 14-day free trial (1,000 calls/month, no card — not an ongoing plan; subscribing keeps the same key working); paid starts at EUR 9.99/mo (Starter), with sanctions screening on the EUR 29.99/mo Professional tier (100,000 calls/month, 300 rpm), higher Scale and Enterprise tiers above, and annual billing at ten months' price for twelve on every paid tier.

Built for the API-native workflow

Every registry identifier is one parameter — company number (UK), SIREN/SIRET (France), NIF/CIF (Spain), CRO number (Ireland), KRS number (Poland), organisasjonsnummer (Norway) — and ?name= is a normalised partial match a type-ahead field can call on every keystroke, across one schema for all six countries. Auth is one bearer key; rate limits scale 10 to 600 requests/minute by tier. A TypeScript SDK (prometiam-risk-api on npm) and an MCP server (prometiam-risk-mcp, also at /mcp) are both published; no Python SDK yet. Free Companies House number, SIREN, NIF, KRS, CRO number and organisasjonsnummer lookup tools run the same call without a key.

Beyond the registry record

Two derived signals on the Prometiam side, neither of them a rating: registry_compliance, which marks companies still on the register that stopped meeting their filing duties (Spain, the United Kingdom, Ireland and Norway), and public procurement — contract awards from Spain, France, the UK, Ireland, Poland and Norway by supplier, buyer, identifier, CPV code and date, plus a beta score for the contracting body itself in Spain and France. Both are dated facts with their source, on the published price and in the free tier; a score is a prompt to look, never a finding of wrongdoing. Public-buyer risk · Procurement screening

At a glance

	Prometiam	Companies House API
Coverage	UK + Spain + France + Ireland + Poland + Norway	UK only
Pricing	Public — 14-day trial, then €9.99 / €29.99 / Custom, monthly or annual	Free
Rate limit	Per-tier; 300 rpm and 100,000 calls/month on Professional	600 / 5min hard ceiling
Auth	Bearer rk_live_*	API key (HTTP Basic)
Sanctions screening	Included on Professional	Not provided
Corporate events	Normalized into typed events	Raw filings — you classify them
PSC data	Included in person/company endpoints	Available via separate endpoints
Insolvency notices	Included in /search and /records/{id}	Available via separate Gazette feed
SLA / support	Yes on paid tiers	None — public service

Frequently asked questions

Is the Companies House API really free?: Yes. The UK government provides it free as a public service. There is no paid tier — meaning the 600 requests / 5-minute rate limit is the hard ceiling.
Does Prometiam replace the Companies House API?: For UK-only low-volume use cases, no — and we would not recommend it. For multi-country (UK + EU) use cases, batch enrichment that exceeds the CH rate limit, or any workflow that needs sanctions screening in the same call, yes.
Where does Prometiam UK data come from?: From the official Companies House sources — bulk product files plus the daily delta feed, plus The Gazette for insolvency notices. Same data lineage as the CH API; Prometiam normalizes it into a multi-country schema and adds sanctions screening.
Can I use both the CH API and Prometiam together?: Yes. Common pattern: use CH for real-time filing-event consumption and Prometiam for batch enrichment, multi-country queries, and sanctions screening.
Does Prometiam cover Persons with Significant Control (PSC)?: Yes. PSC data for UK companies is embedded in /companies/{id} and /people/{id} responses, and the director-network graph at /directors/network exposes cross-company linkages.
How does pricing compare?: CH is free with a hard rate limit. Prometiam has a 14-day free trial (1,000 calls/month, no card, not an ongoing plan); paid starts at €9.99/mo for 10,000 calls/month (Starter), or €29.99/mo for 100,000 calls/month with full sanctions screening (Professional), with annual billing at ten months' price for twelve. The right comparison is "free CH + paid sanctions vendor + paid EU vendor" vs "Prometiam Professional at €29.99/mo".