7 Mistakes Defense Contractors Make When Choosing a CMMC MSP
The CMMC managed services market is full of providers who’ve added CMMC language to their websites without meaningfully changing their capabilities. Defense contractors who choose the wrong CMMC MSP find out the hard way—during a C3PAO assessment, or worse, when they lose a contract. Here are seven mistakes we see repeatedly, and how to avoid them.
Mistake 1: Choosing Based on Price Alone
CMMC compliance is a high-stakes requirement with real contract consequences. A provider offering CMMC managed services at half the market rate is almost certainly cutting scope somewhere—whether it’s 24/7 monitoring coverage, depth of documentation support, or the qualifications of their staff. Price should be a factor, but it should never be the deciding factor. The cost of a failed CMMC assessment dwarfs any monthly savings from a cheaper provider.
Mistake 2: Not Verifying CMMC-Specific Experience
General managed services experience does not translate to CMMC competence. Ask specifically: how many CMMC Level 2 assessments has this provider supported? Can they name controls they’ve implemented? Do they have staff with CMMC certifications (CCP, CCA)? Providers who answer vaguely probably haven’t done the work.
Mistake 3: Assuming GCC-High Configuration Is Standard
Microsoft 365 GCC-High is not the same as commercial Microsoft 365, and most MSPs have more experience with the commercial version. Configuring a GCC-High tenant for CMMC compliance—Conditional Access policies, DLP rules, Microsoft Purview sensitivity labels, Microsoft Sentinel integration—requires specific expertise. Verify your MSP has hands-on GCC-High experience, not just general Microsoft credentials.
Mistake 4: Ignoring Assessment Boundary Implications
Your CMMC MSP is inside your assessment boundary. Their systems, their staff’s access, their tools—all of it is in scope. If your MSP hasn’t thought carefully about how they fit into your assessment boundary, they could be creating findings rather than preventing them. Ask explicitly: how does your service delivery model affect our assessment boundary?
Mistake 5: Signing Without Clear Scope Documentation
Vague MSP contracts are a major source of compliance gaps. If the contract doesn’t specify which CMMC controls the MSP is responsible for implementing and maintaining, you’ll discover the gaps at assessment time. Every managed services agreement for a defense contractor client should include a control responsibility matrix—who owns what, documented and signed.
Mistake 6: Not Planning for Ongoing Compliance, Just the Initial Assessment
CMMC is a triennial certification with continuous compliance obligations in between. Contractors who hire an MSP to get through the first assessment and then coast often discover that their compliance posture has degraded by the time reassessment comes. Your CMMC MSP should be providing ongoing documentation maintenance, continuous monitoring, and annual compliance reviews—not just assessment sprint support.
Mistake 7: Underestimating the Importance of Mission Alignment
Defense contracting isn’t just another vertical. The underlying mission—supporting national security—demands a certain gravity and urgency that commercial IT providers may not feel. VSO was founded by veterans who treat CMMC as an extension of the mission, not a compliance checkbox. That mindset shows up in how we respond to incidents, how we prioritize remediation, and how we communicate with our clients.
Conclusion
Avoiding these seven mistakes will significantly improve your odds of finding a CMMC MSP who can actually deliver. Take the time to evaluate carefully—your contracts depend on it.
🟢 Ready to evaluate VSO against your requirements? We’re confident in our capabilities and welcome the scrutiny. Schedule a discovery call today. — CMMC Managed Services | Contact VSO
Frequently Asked Questions
How long does it take to switch CMMC MSPs if our current provider isn’t working?
Transitions typically take 60–120 days. Plan carefully to avoid a compliance gap during the transition period. Your new MSP should provide a detailed transition plan that maintains continuity of all security monitoring and documentation.
Should we get multiple proposals before choosing a CMMC MSP?
Yes, always. Three proposals is a reasonable minimum. Compare not just pricing but scope specificity, experience documentation, and the quality of their responses to your technical questions.
Is it a red flag if an MSP can’t provide references from defense contractor clients?
Absolutely. References from other DIB contractors are the strongest validation of CMMC competence. A provider without any should be asked to explain why before you proceed.
What credentials should CMMC MSP staff hold?
Look for Certified CMMC Professionals (CCP) and Certified CMMC Assessors (CCA) at the individual level, and RPO designation at the organization level. Microsoft certifications in Azure Government and Security are also relevant for technical staff.
Can we use one MSP for managed services and a different one for CMMC compliance?
This split model creates accountability gaps. Unless you have a very clear contractual delineation of responsibilities, having two providers for overlapping services tends to result in neither owning CMMC compliance fully.
