What due diligence tools do UK angel investors use?

Due diligence tools split by what they read. The registers by hand and Company Check read the filed record. Xapien reads global media and litigation. Startup Due Dil and ChatGPT or Claude read the documents you give them. Tero reads the register, the courts, the market and the web, and cites each figure.

Is ChatGPT enough for due diligence on a UK startup?

They read what you paste and what they can search, and they reason well over it. They do not read Companies House filings, the FCA register, sanctions lists or the courts unless you fetch those yourself, and their answers do not link to filed documents. Use them for questions about a deck. They do not verify.

What should a due diligence report cite?

The filed document behind each figure: the SH01 for a round's price and size, the confirmation statement for ownership, the accounts for revenue, the FCA register entry, the Gazette notice. If a tool gives a number without a source, treat it as the founder's claim restated.

How much do due diligence tools cost for an individual angel?

At the time of writing: the registers are free. Tero's first report is free, then £10 a report or plans from £10 a month. Company Check is £20 a report or £35 a month. Startup Due Dil is $49 a report or $449 a month. Xapien and Beauhurst price for teams.

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The best due diligence tools for UK angel investors (2026): what each one checks

Tero team

The team behind Tero

5 min read

Updated 10 September 2026

Due diligenceTools

Key takeaways

Diligence on a UK startup is four checks. The filed round against the pitch, the founders' histories, the market and the competition, and a source behind every figure. Score a tool on all four.
The register is the benchmark. Companies House, The Gazette and the FCA register are free and authoritative. Every tool here either reads them for you or asks you to.
AI earns its place by reading, not by writing. A model that fetches the SH01, the confirmation statement and the courts does an evening's work in minutes. A model that only summarises the deck adds a well-written guess.

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Run due diligence on any UK company. Nine AI agents read the registers, the courts and the founders' histories. Every figure cited.
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Companies HouseFCAGazetteCourtsSanctions

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First report free, then plans from £10 a month. Descriptive verdicts, never a recommendation.

Before the cheque there is a decision, and most of it is checkable. A UK company files the price of every round, its shareholders once a year, its accounts, its charges, and eventually its death. Its founders leave a trail across the register, the courts and the disqualified-directors list. Its market leaves a trail in traffic and search data. The due diligence tools on the market read some of that trail. None of them replaces a conversation with the founders. This guide sets out the four checks, then scores seven tools on how much of the trail each one reads, and whether it shows you where each figure came from. Tero sits the same tests as everyone else.

#	Tool	Register filings	Founder background	Market and competition	Citations	Beyond the UK	Price	Score
1	Tero	AI reads SH01, CS01, accounts	AI: directors, courts, sanctions	Semrush: traffic, search, rivals	Every figure, to the document	Live web; UK companies only	First report free, then £10	9.2/10
2	The registers by hand	The primary record, PDF by PDF	Officers, Gazette, courts	None	It is the source	UK only	Free	6.7/10
3	Xapien	Corporate records; not the round	Global media, litigation, adverse	None	Every report source-cited	Worldwide, any language	Team plans, on request	5.8/10
4	Company Check	Accounts, charges, CCJs	Directors and their companies	None	Register fields, few document links	UK only	£20 a report, £35 a month	5.0/10
5	Beauhurst	Verified rounds and valuations	Directors on record	Sector and grant data	Sources on record	UK only	£24,500 a year and up	4.2/10
6	Startup Due Dil	Your documents, not filings	Public web	Public web	Partial	Any country, web only	$49 a report	4.2/10
7	ChatGPT and Claude	None	What it can search	General web	Web pages at best	Any country, web only	About £20 a month	3.3/10

Full Partial NoneHow the score is built: 6 tests, each scored full (2), partial (1) or none (0): reads the Companies House filings: the SH01 round, the confirmation statement, the accounts; checks the founders: other companies, disqualifications, courts, sanctions; reads the market and the competition: traffic, search, rivals; cites every figure to its source; covers beyond the UK register: global media, other jurisdictions; priced for an individual angel. Points out of 12, shown out of ten. Tero sits the same tests. It scores half on coverage beyond the UK: it searches the live web but reads only the UK register. Prices as at September 2026.

1Tero9.2/10

Register filings:: AI reads SH01, CS01, accounts
Founder background:: AI: directors, courts, sanctions
Market and competition:: Semrush: traffic, search, rivals
Citations:: Every figure, to the document
Beyond the UK:: Live web; UK companies only
Price:: First report free, then £10

2The registers by hand6.7/10

Register filings:: The primary record, PDF by PDF
Founder background:: Officers, Gazette, courts
Market and competition:: None
Citations:: It is the source
Beyond the UK:: UK only
Price:: Free

3Xapien5.8/10

Register filings:: Corporate records; not the round
Founder background:: Global media, litigation, adverse
Market and competition:: None
Citations:: Every report source-cited
Beyond the UK:: Worldwide, any language
Price:: Team plans, on request

4Company Check5.0/10

Register filings:: Accounts, charges, CCJs
Founder background:: Directors and their companies
Market and competition:: None
Citations:: Register fields, few document links
Beyond the UK:: UK only
Price:: £20 a report, £35 a month

5Beauhurst4.2/10

Register filings:: Verified rounds and valuations
Founder background:: Directors on record
Market and competition:: Sector and grant data
Citations:: Sources on record
Beyond the UK:: UK only
Price:: £24,500 a year and up

6Startup Due Dil4.2/10

Register filings:: Your documents, not filings
Founder background:: Public web
Market and competition:: Public web
Citations:: Partial
Beyond the UK:: Any country, web only
Price:: $49 a report

7ChatGPT and Claude3.3/10

Register filings:: None
Founder background:: What it can search
Market and competition:: General web
Citations:: Web pages at best
Beyond the UK:: Any country, web only
Price:: About £20 a month

Full Partial NoneHow the score is built: 6 tests, each scored full (2), partial (1) or none (0). Points out of 12, shown out of ten. Tero sits the same tests. It scores half on coverage beyond the UK: it searches the live web but reads only the UK register. Prices as at September 2026.

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Tero

AI due diligence from the filed record

9.2/10

11 of 12 points

Give it a company name, a website or a deck. Tero builds an evidence pack from Companies House, the FCA register, sanctions lists, The Gazette, court judgments, Semrush traffic and search data, and the live web. Nine AI research agents run over it in parallel, one per module, then a second agent challenges each claim before the report states it. Every figure links to its source and the verdict is descriptive. It reads UK companies only.

Reads: Companies House, FCA, OFSI, Gazette, courts, Semrush, web
Cites: Every figure, to the document
Time: About fifteen minutes

For

Powered by AI agents: nine researchers and a sceptic on every report
Prices the round from the SH01, and compares it with the deck
Founder background across the registers and the courts
Priced for one person

Against

UK only
A report takes about fifteen minutes
A finding, never a recommendation

Check a company free See an example report →

Sources, checked 10 September 2026: tero.capital/pricing; example report

The registers by hand

Companies House, The Gazette, the FCA register

6.7/10

8 of 12 points

The authoritative sources cost nothing: company filings, insolvency notices, authorised firms and individuals, disqualified directors, court judgments. Reading a year of SH01 PDFs and cross-checking each founder takes an evening, which is why most angels check two sources or none. Tero's free checker reads the first layer in seconds.

Reads: The primary record
Cites: It is the source
Time: An evening per company

For

Authoritative and free
Nothing hidden

Against

An evening per company
No market or competition data
Easy to stop after two sources

The free company checker →

Sources, checked 10 September 2026: Companies House; The Gazette; FCA register

Xapien

AI background reports, worldwide

5.8/10

7 of 12 points

Company and people reports strongest on global media, litigation and adverse coverage, every report cited to its sources. Built for compliance teams, wealth managers and law firms, with plans that start at 250 reports a year. It answers the reputation question well. It does not price a UK round from the SH01, and it does not read the market.

Reads: Global media, litigation, corporate records
Cites: Yes
Time: Minutes

For

Adverse media across languages
Cited to the source
Strong on people

Against

Priced for teams
No UK round or ownership reading
No market or traffic data

Sources, checked 10 September 2026: xapien.com/plans

Company Check

Credit-bureau reports on UK companies

5.0/10

6 of 12 points

Accounts history, county-court judgments, charges, directors and group structure, in credit-report form. Good for whether a company is solvent and who runs it. Silent on the round, the valuation, the pitch and the founders' claims, because it was built for trade credit.

Reads: Companies House, court and credit data
Cites: Register fields
Time: Seconds

For

Cheap
CCJs and charges surfaced

Against

No round or valuation reading
No market data
Built for trade credit

Sources, checked 10 September 2026: companycheck.co.uk; Company Check help centre

Beauhurst

The UK private-company database

4.2/10

5 of 12 points

Analyst-verified coverage of UK rounds, valuations, grants and accelerators, the deepest commercial UK dataset. Built and priced for teams: the public-sector list price starts at £24,500 a year for five users, and commercial pricing is on request. An individual angel's budget does not reach it.

Reads: Filings plus analyst verification
Cites: Sources on record
Time: Instant lookup

For

Deepest UK coverage
Analyst-verified rounds

Against

Institutional pricing
Not a per-company diligence report
No founder background check

Sources, checked 10 September 2026: beauhurst.com/data; G-Cloud 14 pricing document

Startup Due Dil

Ten agents over the deck

4.2/10

5 of 12 points

Ten AI agents read a pitch deck, supporting documents and public sources and return a structured report in about ten minutes. Built mainly for VC and PE firms, with an angel plan on the side. It reads what you give it and the open web, and skips the UK register, so the filed round and the ownership stay unchecked.

Reads: Your documents and the public web
Cites: Partially
Time: About ten minutes

For

Fast structured output
Handles the deck well

Against

No UK register depth
$449 a month for the angel plan
No monitoring after the report

Sources, checked 10 September 2026: startupduedil.com

ChatGPT and Claude

A reasoning partner for the deck

3.3/10

4 of 12 points

Paste the deck and ask: is the market-size claim consistent, what does the cap table imply, what would you ask the founders. Both reason well over long documents. Neither reads Companies House, the FCA register or the courts unless you fetch the documents yourself, and neither links a figure to a filing.

Reads: What you paste, and web search
Cites: Web pages at best; never filings
Time: Seconds

For

Excellent at questions and structure
Cheap and immediate

Against

No register access
No citations to filed documents
Confident about numbers it has not checked

Sources, checked 10 September 2026: openai.com/chatgpt/pricing; claude.com/pricing

What UK angel investors need from due diligence tools

The filed round against the pitch. When a UK company issues shares it files an SH01 with the number allotted and the price per share. Multiplied out, that is the valuation investors paid. The deck may say something else. See how to read an SH01.

The founders' histories. Every current and former directorship is public, and so are the disqualified-directors register, county-court judgments, insolvency notices and sanctions lists. A portfolio of dissolved companies is no verdict on its own, but you want to know before you invest.

The market and the competition. Traction claims can be tested against traffic and search data, app-store rankings, live job listings and the competitors' own announcements. The pattern to watch is a deck whose every number sits at the optimistic edge of what the public data supports.

A source behind every figure. A number that links to the filed document can be checked by a co-investor in a minute. A number without a link is a claim. Ask any tool to show its source before you trust the figure.

The gap in the market

The deep tools serve teams. Beauhurst sells verified UK round data from £24,500 a year on its public-sector list. Xapien sells background reports to compliance departments in blocks of 250 a year. Harmonic and Specter feed the sourcing teams of funds. An individual angel writing £25,000 cheques is left with Companies House on a Sunday night, a chat window for the deck, and a folder of PDFs. What the angel needs is one report that reads the register, checks the founders, reads the market and cites its sources, at a price that makes sense for one deal.

Six tests

Reads the Companies House filings. The SH01 for the round, the confirmation statement for ownership, the accounts, the charges. The press release does not count.

Checks the founders. Other companies, disqualifications, court judgments, sanctions lists, with the source shown.

Reads the market and the competition. Traffic, search demand, competitors' presence, from data rather than the deck.

Cites every figure to its source. You can check a number that links to the filed document. A number without a link is a claim.

Covers beyond the UK register. Global media, other jurisdictions, signals the register does not carry.

Priced for an individual angel. A £25,000-cheque angel can afford it without a team budget.

Each test scores full, partial or none. Twelve points is a tool that does the whole check for one person.

Where due diligence tools stop

Three things no tool changes. A clean check is a finding. It guarantees nothing: most private companies publish very little, and the skill is separating "not disclosed" from "contradicts the pitch". The founders still need a conversation, and the tool should give you the questions for it. And the decision stays yours. Information, not investment advice.

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.

All company pages →

Questions this guide answers

What due diligence tools do UK angel investors use?: Due diligence tools split by what they read. The registers by hand and Company Check read the filed record. Xapien reads global media and litigation. Startup Due Dil and ChatGPT or Claude read the documents you give them. Tero reads the register, the courts, the market and the web, and cites each figure.
Is ChatGPT enough for due diligence on a UK startup?: They read what you paste and what they can search, and they reason well over it. They do not read Companies House filings, the FCA register, sanctions lists or the courts unless you fetch those yourself, and their answers do not link to filed documents. Use them for questions about a deck. They do not verify.
What should a due diligence report cite?: The filed document behind each figure: the SH01 for a round's price and size, the confirmation statement for ownership, the accounts for revenue, the FCA register entry, the Gazette notice. If a tool gives a number without a source, treat it as the founder's claim restated.
How much do due diligence tools cost for an individual angel?: At the time of writing: the registers are free. Tero's first report is free, then £10 a report or plans from £10 a month. Company Check is £20 a report or £35 a month. Startup Due Dil is $49 a report or $449 a month. Xapien and Beauhurst price for teams.

Tero runs these checks automatically.

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