Sometimes contractors assume certain controls simply do not apply and mark them as “N/A” in their system security plan (SSP). That decision may seem harmless or even efficient, yet it can hide serious implications for achieving Cybersecurity Maturity Model Certification (CMMC) compliance requirements. In the context of preparing for a CMMC Accreditation Body (C3PAO) audit, seemingly innocuous omissions can raise red flags and threaten the entire assessment process.
Why “N/A” Flags Raise Red Alarms in Your SSP
When an organization marks many controls as “N/A” in the SSP, assessors often interpret this as avoidance rather than a considered decision. The official assessment criteria state that control ratings can be MET, NOT MET, or NOT APPLICABLE, but the methodology emphasises full implementation where applicable.
If a contractor chooses “N/A” without documented justification, it can signal insufficient understanding of scope or control relevance—both common CMMC challenges. A clean SSP should map each control to evidence or documentation rather than defaulting to “not applicable.”
In a CMMC Pre Assessment, one of the first tasks is verifying that the organization has considered each control from either the CMMC level 1 requirements or CMMC level 2 requirements. Failing to properly assess applicability creates a weak foundation for the assessment. Consultants providing CMMC compliance consulting often see this as an early warning sign that the organization might struggle during the Intro to CMMC assessment.
The Hidden Compliance Risk of Blanket “N/A” Responses
Marking large groups of controls as “N/A” can undermine your organisation’s ability to show a consistent security posture. Controls from the CMMC RPO or scoping guide may initially appear irrelevant, but on closer inspection, they often touch shared systems or third-party services. According to guidance, a requirement can still be considered applicable even when some assessment objectives are labeled “N/A.”
When a contractor overlooks these interdependencies, the SSP may show gaps—not because controls are missing, but because they were never evaluated for applicability. That creates risk when an auditor drills into shared responsibility or inherited controls.
External auditing firms or those offering government security consulting advise that these blanket “N/A” responses impair traceability of control implementation. Auditors expect to see how each control connects to your environment, your workflows, and your risk model—not just a checkbox that says “irrelevant.”
Assessors View “N/A” as a Control You’ve Just Ignored
To an auditor from a C3PAO, any control marked “N/A” still invites scrutiny. The auditor may probe why the control was deemed inapplicable, examine whether supporting documentation exists, and check whether the SSP clearly records the reasoning. This scrutiny aligns with the formal assessment criteria in the level 2 guide.
If the evidence trail is weak or missing entirely, your organisation risks being flagged for a NOT MET finding—despite choosing “N/A.” The logic is simple: omission of justification equals omission of implementation review.
In practice, consulting for CMMC often surfaces that control categories marked “N/A” without context later become audit focus areas. Control areas such as audit logging, remote access, or configuration management may appear non-applicable initially, but during the audit the assessor will want to verify why they are out of scope. Without this, you may face remedial action or deeper audit findings.
Documented Justification: No “N/A” Without Evidence
One of the foundational requirements of an SSP is documenting how controls apply to the system and environment of operation. When marking a control as “N/A,” you must attach credible justification—e.g., the control lies entirely within an inherited service provider that manages it, or the control does not interact with CUI at all. This justification must align with the CMMC scoping guide and your own declared boundaries.
Without that written rationale tied into the SSP, the “N/A” designation lacks legitimacy and may be challenged during a formal assessment.
In the broader context of compliance consulting, the organisations that maintain robust documentation around their decisions tend to better withstand audits. The compatible evidence includes policies, workflow diagrams, vendor contracts, and internal logs. A control labelled “N/A” without any of these leaves your SSP hollow and increases the chance of audit-related complications.
How “N/A” Can Undermine Shared Responsibility Models
Many modern IT setups involve service providers, cloud environments, and managed services—creating split responsibilities between contractors and external partners. When an organisation marks controls as “N/A” simply because a provider claims responsibility, it may overlook the need to verify and document that provider’s implementation. The assessment criteria allow for inherited controls but still expect the organisation to show how they hold those providers accountable.
If your SSP lists inherited controls as “N/A” without linking to the provider agreement or oversight mechanisms, you expose yourself to risk when auditors ask for proof of control.
This is a common stumbling block noted in CMMC compliance consulting engagements: recognising “shared responsibility” and then documenting how each part is managed, monitored, and evaluated. Simply marking controls as not applicable because “someone else handles it” doesn’t satisfy the requirements of a formal CMMC assessment.
When “N/A” Means You’re Off the Hook — Not for Compliance
It’s tempting to think marking a control as “N/A” means you can skip it entirely and move on. That mindset poses a misconception. The official guidance states that a control may still be applicable even if certain assessment objectives within it are inapplicable.
In other words, the “N/A” marking doesn’t guarantee relief—it often triggers more questions from assessors.
Contractors preparing for a CMMC assessment should treat “N/A” not as shorthand for “not needed,” but as a decision state requiring explicit justification and governance. Those working with CMMC consultants or involved in government security consulting frequently flag this misunderstanding as among the most common causes of audit delay or remediation.
Replacing “N/A” with Planned or Inherited Implementation
Instead of defaulting to “N/A,” best practice suggests marking controls as “Planned,” “Inherited,” or “Implemented,” depending on their state within your system. That nuanced approach conveys to auditors that your organisation examined the control, decided its status, and recorded how it will be addressed. This aligns better with how the CMMC Pre Assessment process works.
A planned control can be tracked in your POA&M (Plan of Action & Milestones) and demonstrates commitment to achieving CMMC level 2 compliance rather than avoiding the question.
One benefit of this method is that it sets up your readiness for the Intro to CMMC assessment. Analysts in compliance consulting often advise that those who treat their SSP as a living document with rational decisions ahead of time tend to face fewer audit surprises and smoother engagements with C3PAOs.
Your SSP at Risk: “N/A” Doesn’t Pass the Audit Trail Test
An SSP with numerous “N/A” marks risks failing the audit‐trail test: where is the evidence, how do you show applicability, and what oversight exists for shared controls? Auditors will expect your documentation to show how each control fits into your environment or why it does not. That expectation comes directly from the CMMC level 2 assessment guide.
If your SSP lacks that depth, your effort to meet CMMC compliance requirements may collapse late in the process rather than succeed smoothly. Contractors working with experienced CMMC RPOs understand that the credibility of an SSP comes from transparency, traceability and documented evaluation—not from sweeping “not applicable” selections. For those seeking support in this area, MAD Security provides end-to-end consulting for CMMC readiness, including SSP review and readiness strategy.
