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KYB checks: what pass, refer and fail mean

A KYB check tests a company against the Companies House register and other public records. Fail means a check failed, refer means a person should review it, and pass means every check that could run passed.

A KYB ("know your business") check runs a set of automated checks on a company and gives one result: pass, refer or fail. Each check has a PDF certificate you can keep on file.

Running a check

In the web app (Pro and Team): open a list and click KYB next to a company, select several and click Run KYB, or click KYB-check all. Pro includes 250 checks a month and Team 1,000. The result appears next to each company as "KYB pass", "KYB refer" or "KYB fail". Click it to open the PDF certificate.

Through the API (Starter and above): send POST /kyb/check with the company number. You can also send the name and postcode you were given, so we can compare them with the register.

What the results mean

Fail: at least one check failed

For example:

  • the company number is not on the register;
  • the company is dissolved, or in liquidation or another insolvency process;
  • the name you gave does not match the registered name;
  • The Gazette has published an insolvency notice about the company in the last 24 months.

Refer: nothing failed, but a person should look

For example:

  • Companies House has proposed striking the company off, or it is in a voluntary arrangement;
  • the name you gave is similar to, or a former name of, the registered name;
  • the postcode you gave does not match the registered office;
  • the company is less than six months old;
  • its accounts or confirmation statement are overdue;
  • no person with significant control is registered, or the PSC or director records do not match;
  • a director or PSC has a possible match on the disqualified directors register. These are name matches, so confirm the person's identity before you act on them;
  • a director or PSC has missed their identity verification deadline.
  • the company, a previous name, a PSC or an officer is a possible or strong match on a sanctions list. A name match is not a finding that anyone is sanctioned: review it against the official entry. See Sanctions screening.

Pass: every check that could run passed

Some results also carry warnings, such as negative net assets, 50 or more companies at the same registered office, or sanctions screening that could not cover every list or name. Warnings are for information only and do not change the result.

A check that could not run, for example because a record was not available, is shown as "not checked".

What KYB does not cover

  • Politically exposed persons (PEPs). We do not check PEP lists. Sanctions lists are checked: see Sanctions screening.
  • Identity documents. We do not see or verify passports or other ID.
  • Credit risk. KYB is not a credit check.

KYB results are automated information from public records. They are not legal or compliance advice. Use them alongside your own procedures.

Last updated 2 October 2026

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