API Live

The dependable
Companies House API.

Structured financials, director networks, and intelligent caching on top of Companies House. Stop wrestling with iXBRL and rate limits - get clean JSON in one call. Submit 500 companies as a batch and we handle the rest in the background. Now with ECCTA identity verification compliance monitoring.

No Companies House API key needed. One Registrum key covers everything.

24h
Company cache
7d
Financials cache
5
Free lookups/day

# Request

curl -H "X-API-Key: reg_live_..." \

"https://api.registrum.co.uk/v1/company/00445790"

# Response

{

"company_name": "TESCO PLC",

"company_age_years": 104,

"turnover": 68190000000,

"accounts_overdue": false,

"credits_remaining": 49

}

Search any UK company

Sign up free to search live UK company data — financials, directors, and ownership.

Free API key required — sign up below in seconds · Get your free key

Everything Companies House doesn't give you

Structured financials parsed from iXBRL. Director networks. Beneficial ownership chains. ECCTA compliance. All in clean JSON — no CH API key needed.

7-day cache

Structured Financials

iXBRL filings parsed into clean JSON — turnover, net assets, profit/loss, employees. Current and prior year, all values in actual GBP. Explicit data_quality metadata so you know exactly what's available.

Try with any company →
24h cache

Director Networks

One endpoint traverses the full board network to 2 degrees. Returns all companies sharing directors, sorted by connection strength. Discover related entities not obvious from a single filing.

Try with any company →
24h cache

Beneficial Ownership (PSC)

The PSC register decoded and traversable. Natures of control in plain English. Corporate PSCs include their company number — pass it to the chain endpoint to find the ultimate beneficial owner.

Try with any company →
Pro/Enterprise

ECCTA Compliance

Monitor director and PSC identity verification under the Economic Crime and Corporate Transparency Act 2023. One call returns a risk rating, verified count, and list of unverified persons.

See live demo →
500 companies/batch

Async Batch Enrichment

Submit 500 company numbers in one POST. We enrich them in the background, automatically managing the CH rate limit. Poll for results — no timeouts, no queuing logic on your side.

POST /v1/batch
{"company_numbers": ["00445790", ...]}

→ {"batch_id": "3fa85f64-...", "status": "queued"}
How it works →

Integration in 10 minutes

01

Get your API key

Enter your email below. Your free key arrives instantly — no credit card, no forms.

# 5 free calls/day — no credit card
X-API-Key: reg_live_...
02

Make your first call

Pass the API key in the header. Any HTTP client works — curl, Python, Node, whatever you use.

curl -H "X-API-Key: reg_live_..." \
  "https://api.registrum.co.uk/v1/company/00445790"
03

Get clean, structured data

JSON back in milliseconds. Cached, enriched, with explicit metadata about what's available.

{
  "company_name": "TESCO PLC",
  "turnover": 68190000000
}

Simple, transparent pricing

No setup fees. No hidden costs. Upgrade or cancel any time.

Free
£0/forever
5 lookups / day
Burst: 10 / min
  • All core endpoints
  • Financials + director network
  • PSC beneficial ownership
  • Async batch (quota-limited)
  • Email support
Get started
Web
£19/per month
500 calls / month
Burst: 30 / min
  • Everything in Free
  • 500 API calls / month
  • 50 calls / day limit
  • Unlimited web browsing on registrum.co.uk
Most popular
Pro
£49/per month
4,000 calls / month
Burst: 100 / min
  • Everything in Web
  • 4,000 API calls / month
  • PSC chain & UBO traversal
  • ECCTA compliance endpoint
  • SLA uptime commitment
Enterprise
£149/per month
Unlimited calls
Burst: 500 / min
  • Everything in Pro
  • Unlimited API calls
  • Dedicated support
  • Custom rate limits on request
Contact us
FeatureFreeWebProEnterprise
Company profile & filings
Director list
Structured financials (iXBRL)
Fuzzy company search
PSC beneficial ownership
Async batch enrichmentquota-limitedquota-limited
Director network (depth 1)
Director network (depth 2)
PSC chain & UBO traversal
ECCTA compliance monitoring
KYB pack
SLA uptime commitment

Batch enrichment consumes credits per company processed (1 credit each). Free and Web plans are quota-limited by their monthly allowance. Director network depth 2 and PSC chain are Pro/Enterprise only as each request can consume up to 30+ upstream API calls.

Create your free account

Your email is your login. You get an API key for code integrations and a dashboard to look up companies in your browser. No credit card required.

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