UK Cyber Essentials covers 20.6% of NIST SP 800-171 Rev 3
20 of the 97 controls in NIST SP 800-171 Rev 3 are already satisfied by evidence you collected for UK Cyber Essentials. 77 are genuine gaps. Every claim below was judged against both control sets and then argued against; the ones that did not survive are published further down with the reason each failed.
This number is directional. It says how much of NIST SP 800-171 Rev 3 your UK Cyber Essentials evidence satisfies. The reverse pair is a different number, often very different, because a security standard has enormous depth for access control and almost none for lawful basis or data subject rights.
55 candidate mappings were examined and 0 were removed. Signed off 2026-08-19, review level machine verified. Mappings were judged by Claude Code rather than read line by line by a practitioner. Every claim shows its reasoning so you can check it. Ask and a practitioner will review this pair.
Where the gaps are
Coverage is never evenly spread. A source standard usually satisfies one part of a target almost completely and barely touches another, and which part is which is the thing worth knowing before you plan the work.
Theme level, not control level, deliberately. The per-control list of what is evidenced and what is a gap is the report itself, so publishing it here would be publishing the thing being sold.
Claims that held
A sample. Each one names the control whose evidence does the work, the control it satisfies, and why.
Both require accounts to be disabled or removed once no longer required.
Both require a documented approval process before an account is established.
Both require access and privileges to be granted only under approved authorisation.
Both require authentication against a unique account before access is granted.
Both require periodic review of privileges and removal of those no longer needed.
Both require privilege grants to be controlled to what the task actually needs.
Both require non-privileged accounts to be used for routine non-administrative work.
Both restrict administrative accounts to approved designated personnel.
Claims that did not hold
Nothing proposed for this pair was rejected in review. That is unusual and worth knowing rather than hiding: it means the candidate set was small and every candidate held.
The full report
Everything above is a sample. The report is every evidenced control and every gap, with the reasoning and the source document behind each one, in a form you can hand to an assessor. $299, emailed immediately.
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