About CompanyStack

UK Company Intelligence, Built for Developers

CompanyStack provides instant access to comprehensive UK company data through a modern, developer-first API. We aggregate Companies House bulk data, PSC registers, and live filings into a single, fast, intelligent platform.

Our Mission

The Companies House API is powerful but limited — restrictive rate limits, no bulk access, and no intelligence layer. CompanyStack solves this by maintaining a complete, enriched database of every UK company, updated daily.

We believe company data should be fast, affordable, and intelligent. Whether you're building a fintech KYC flow, a B2B prospecting tool, or regulatory compliance software — you shouldn't have to worry about rate limits or stale data.

What We Offer

  • Full-text & autocomplete search across 5.7M+ companies
  • AI-powered health scores and risk intelligence
  • 15.4M+ Persons of Significant Control records
  • Industry & geographic analytics by SIC code & postcode
  • Real-time proxy to Companies House for live filings
  • Corporate group mapping & director network analysis
  • Enterprise due diligence reports
  • Watchlist monitoring with change alerts

CompanyStack by the Numbers

5.7M+
UK Companies
15.4M+
PSC Records
2.6M+
Postcodes Mapped
<50ms
Avg Response Time

Built with Modern Technology

PostgreSQL

Full-text search with tsvector, trigram similarity, and optimized indexes across 5.7M+ rows.

Hono Framework

Ultrafast Node.js API with middleware for auth, rate limiting, caching, and CORS.

Svelte 5

Latest Svelte with runes ($state, $derived) for a blazing-fast reactive portal.

Companies House

Real-time proxy integration for live officer, filing, PSC, and charge data.

In-Memory Cache

Analytics and frequently-accessed data cached with automatic TTL refresh.

Daily Updates

Automated differential updates from Companies House bulk data products.

Built by BlackPeak CFO

CompanyStack is a product of BlackPeak CFO Ltd, a London-based technology company focused on financial intelligence and data infrastructure. We build tools that make business data accessible and actionable.