What to Know About the CMMC Final Rule: Key Changes and How to Prepare

The long-anticipated Cybersecurity Maturity Model Certification (CMMC) Final Rule, published on September 10, 2025, officially became effective November 10, 2025. This shift from voluntary guidance to mandatory, enforceable contract requirements under the Defense Federal Acquisition Regulation Supplement (DFARS) marks a turning point for every organization that supports the federal defense supply chain. This critical milestone also signifies that full implementation is just beginning.

In this article, we’ll explain the implications of the CMMC Final Rule, why it’s important for defense contractors, and steps to take now to prepare for compliance.

What is the CMMC Final Rule?

The CMMC program was first proposed in 2020 to standardize cybersecurity across the defense industrial base (DIB). The Department of War (DoW) then introduced an updated version, known as CMMC 2.0, in 2021 to simplify and align the program with NIST SP 800-171. In October 2024, the DoW issued the CMMC Program Rule (32 C.F.R. Part 170), which became effective that December and established the framework and oversight structure.

The final DFARS amendment took place in September 2025, making CMMC a contractual, legally binding requirement across applicable defense contracts. Compliance with CMMC is now tracked through annual affirmations of continuous compliance posted in the Supplier Performance Risk System (SPRS), signaling the need for ongoing adherence.

There are three CMMC levels:

Why the CMMC Final Rule Matters for Defense Contractors

As of November 2025, contracting officers must include CMMC clauses in solicitations and enforce compliance verification through SPRS. Enforcement of the CMMC Final rule applies to all contractors and subcontractors within the DoW supply chain handling FCI or CUI. The DoW will introduce requirements across solicitations in four stages, over a three-year phased rollout, detailed below. Despite this gradual enforcement approach, there is still an urgency for early preparation.

Companies that fail to maintain a current CMMC status will be ineligible for new contracts, renewals, or option exercises. This presents business risks for those who are not ready before the phased rollout reaches their current contact obligations and future business opportunities. Alternatively, organizations who achieve CMMC certification early on will have a competitive advantage by demonstrating reliability and security maturity to government partners.

CMMC Phased Implementation Timeline and Requirements

During the first three years (and phases) of this rollout, programs have the discretion to decide when and how to include CMMC requirements, meaning some may require Level 2 or Level 3 certification at any point. In anticipation of this variability, contractors should proactively prepare to be faced with potentially accelerated requirements.

How to Prepare for CMMC Compliance

Organizations should start preparing now to ensure they don’t miss out on any contracts due to lack of compliance and to avoid a last-minute scramble as the rule begins to take effect.

Below are strategic steps to prepare for compliance with the CMMC Final Rule:

1. Perform a Gap Assessment

2. Train and Mobilize Stakeholders

CMMC compliance needs to be an organization-wide effort, requiring cross-team collaboration. Ensure leadership, IT, procurement, legal, and compliance teams understand the new obligations, reporting requirements, and enforcement timeline. Identify and designate personnel who will be responsible for ensuring annual affirmation of continuous compliance. Engage leadership teams for strategic decision-making and resource allocation with CMMC requirements in mind.

Ensure that internal processes are established and monitored across teams. Review current and pending DoW contracts for CMMC requirements and ensure proposals feature all necessary information. Monitor solicitations for awareness of required CMMC Levels. Establish a process to ensure subcontractors also comply with CMMC requirements at the necessary level and update subcontract templates accordingly.

3. Engage a Trusted Partner

4. Implement Continuous Monitoring

As you plan for the rollout, monitor DoW guidance for updates as the phased implementation progresses. Failure to comply will become a barrier to entry, so preparation should begin now.

Moving Forward Toward CMMC Compliance

The CMMC Final Rule signals that cybersecurity is a contractual foundation of the DoW supply chain. For contractors, the path forward requires moving from compliance planning to actionable, verified readiness.

Organizations should invest now in assessments, training, and continuous monitoring to not only meet federal requirements, but to strengthen their overall security posture and position themselves as trusted partners.

To learn more about preparing for CMMC certification or beginning your compliance journey, contact us today. In the meantime, discover additional helpful insights here:

• What DoD Contractors Need to Know About the 32 CFR CMMC Rule and Its Effect on Vendors

• Your Guide to CMMC vs. FedRAMP
• Determining Your Level of CMMC Compliance: The Importance of CUI