AWS Well-Architected Security Pillar covers 43.3% of NIST SP 800-171 Rev 3
42 of the 97 controls in NIST SP 800-171 Rev 3 are already satisfied by evidence you collected for AWS Well-Architected Security Pillar. 55 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.
What this leaves you to do
NIST SP 800-171 Rev 3 has 97 controls. Holding AWS Well-Architected Security Pillar already evidences 42 of them, so the work in front of you is 55 controls, not 97, which is 57% of the standard rather than all of it.
That is the whole claim. We do not know your hourly rate, how long a control takes you, or how many people you have, so there is no figure here in dollars or weeks. Every number in that sentence comes from the two counts above it and can be re-derived from the free tools without taking our word for any of it.
This number is directional. It says how much of NIST SP 800-171 Rev 3 your AWS Well-Architected Security Pillar 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.
145 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.
Lifecycle-driven grant and revocation on joiner mover leaver events evidences account creation, modification and removal.
Layered IAM, resource, KMS and endpoint policies enforce approved authorizations on data resources.
Least privilege IAM policies granting only required actions and conditions are direct access enforcement evidence.
Restricting flows to only those each component needs is direct information flow enforcement evidence.
Unused access findings and last accessed data evidence periodic review and removal of privileges.
Policies granting only specific required actions and resources is the core least privilege evidence.
Routing administrative access through automation and managed session tooling is direct managed access point evidence.
Enabling CloudTrail, flow logs and application logs across accounts defines and implements the logged event types.
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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