Companies House API for newly registered companies

    The official Companies House API gives you any one company's record. It cannot tell you which companies registered last week in construction in Manchester. NewcoSignal's read-only API can, with a sector, a shell flag, a contactable-by-post flag and a verified website on every record.

    Official API or NewcoSignal API?

    You want toCompanies House APINewcoSignal API
    Look up one company by numberYes, freeYes
    Officers, filings, charges, PSCsYes, full historyOfficers and key dates
    Companies registered this week in a sector and townNo search by sector or locationYes: sector, SIC, postcode, age, type
    Plain-English sector for each companySIC codes onlyYes, 20 sectors and 100 sub-sectors
    Shell-company and postal-reachability flagsNoYes
    Verified website, email, LinkedInNoWhere verified
    Matches for your saved searchesNoYes
    Raw stream of every change on the registerYesNo
    Dated business signals (new lending, directors, owners, insolvency) by sector and areaNoYes, Signals API
    CostFreeFree demo, then from £49 a month + VAT

    Endpoints

    All endpoints are read-only and return JSON. Send your key in the Authorization header.

    • GET /api/v1/companies searches the register. Filters: sic_category, postcode, age, company_type, company_status, name, has_website, hide_shells, reachable_by_post, page, limit (max 100).
    • GET /api/v1/companies/:companyNumber returns one company.
    • GET /api/v1/matches returns new companies matching your saved searches. Optional days (1 to 90, default 7) and limit.
    curl -H "Authorization: Bearer nh_your_key_here" \
  "https://www.newcosignal.co.uk/api/v1/companies?sic_category=construction&postcode=M&age=new&limit=5"

    Rate limits are 60 requests a minute and 1,000 a day per key, reported in the standard RateLimit-* headers. Contact fields are returned only where we have verified them, never guessed. For dated events such as new lending, new directors and insolvency, see the Signals API; both APIs are documented in the API documentation.

    Frequently asked questions

    Is the Companies House API free?

    Yes. Companies House publishes a free REST API and a streaming API for the whole register; you register for a key on the Companies House developer hub. It gives you the raw record for a company, its officers, filings and charges. What it does not give you is any way to ask for new companies by sector or town, or a sector classification, or a verified website.

    How is the NewcoSignal API different?

    It sits on top of the register and answers the question the official API cannot: which companies registered recently in a given sector and area. Every company carries a plain-English sector, a shell-company flag, a contactable-by-post flag and, where one has been verified against the registration number, a website. It also returns the matches for your saved searches, so an integration can pull exactly what your alerts would have emailed.

    What does the NewcoSignal API cost?

    Every verified account gets a free demo key with 100 records. The Companies API is £49 a month + VAT for 2,500 records, and the Signals API, which adds live events such as new lending, new directors, new owners and insolvency, is £149 a month + VAT for 10,000 records. The Business website plan includes 2,000 API records a month. Full details are on the developers page.

    What are the rate limits?

    60 requests a minute and 1,000 a day per key. Every response carries the standard RateLimit headers. A search returns up to 100 companies a page.

    Can I get the data without writing code?

    Yes. Pro plans export any search to CSV or Excel, Zapier and webhooks push new matches to other tools, and anyone can buy a one-off list of a search from £10 without a subscription.

    Start with a free key

    100 records free, no card needed. Plans, the full reference and code samples are on the developers page.

    See the APIAlerts instead