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The 12-source due-diligence checklist for UK angel investors

Tero team
The team behind Tero
2 min read
Updated 13 July 2026
Due diligenceChecklist
Key takeaways
  • Twelve sources, mostly free. Companies House, SH01 filings, the Gazette, sanctions lists, disqualifications, the courts, the FCA register, adverse media, traffic, app ratings, hiring and reviews.
  • Each check takes minutes; together they take an evening. Which is why most angels check two of them, or none.
  • Absence of data is not adverse evidence. The skill is separating 'not disclosed' (normal for private companies) from 'contradicts the pitch' (a real flag).
Tero for angel investors
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Companies HouseFCAGazetteCourtsSanctions
Check a company free
First report free, then plans from £10 a month. Descriptive verdicts, never a recommendation.
Proper diligence on a UK startup means checking about a dozen sources. Each takes minutes once you know where to look; together they take an evening, which is why most angels check two, or none. The list:

Company & filings

  • Companies House: is the entity real, are filings current, who are the directors and PSCs? Free.
  • SH01 allotment filings: the real price and size of every prior round, and the implied valuation. Free, buried in PDFs.
  • The Gazette: insolvency, winding-up and bankruptcy notices, incl. against founders personally. Free.
  • People

  • Disqualified-directors register: is anyone banned from running a company? Free.
  • Sanctions lists (OFSI, OFAC, UN): a screen every professional investor runs and most angels skip. Free.
  • Court judgments (Find Case Law, The National Archives): litigation involving the company or founders, 2022 onwards. Free.
  • Adverse media: targeted news search for fraud, regulatory action, disputes. Free to do manually.
  • FCA Financial Services Register: essential for anything fintech: is the firm (or founder) authorised, an appointed representative, or neither? Free.
  • Traction & digital

  • Website traffic estimates: does the traffic curve corroborate the claimed growth? Paid data (SEMrush et al.).
  • App-store ratings and review counts: real user counts for consumer products. Free.
  • Hiring boards & LinkedIn headcount: companies hire ahead of growth and freeze ahead of trouble. Free.
  • Reviews (Trustpilot, G2, Reddit): what customers say when the founder isn't in the room. Free.
  • The honest caveat

    A clean check is a finding too, and absence of data is not adverse evidence. Most private companies publish almost nothing; the skill is separating "not disclosed" (normal) from "contradicts the pitch" (a real flag).

    Tero runs all twelve automatically on every screen, adds a nine-module researched report on the market, competition, founders and plan, and lists each check it ran with its result. That's the product: the evening of tab-hopping, done in minutes.
    From the register

    See it on a real filing history

    Three UK companies whose priced rounds Tero has read from Companies House, with implied valuation at each allotment.

    Questions this guide answers

    Which sources should a UK angel check before investing?
    Twelve: Companies House, SH01 filings, The Gazette, sanctions lists, the disqualified-directors register, court judgments, the FCA register, adverse media, web traffic, app-store ratings, hiring boards and reviews. Most are free.
    How long does startup due diligence take by hand?
    Each check takes minutes once you know where to look; together they take an evening. That is why most angels check two sources, or none.
    Is missing data a red flag?
    Not by itself. Most private companies publish very little. The skill is separating 'not disclosed', which is normal, from 'contradicts the pitch', which is a real flag.
    What does a sanctions screen involve?
    Checking the founders and directors against the OFSI, OFAC and UN lists. Professional investors run it as standard and most angels skip it, although the lists are free.
    Tero runs these checks automatically.
    Twelve sources, one gateway. Diligence in minutes, monitoring forever.