The top FedRAMP 3PAO assessors in 2027 are Coalfire and A-LIGN for volume and depth, Schellman for combined FedRAMP and SOC 2 work, and Kratos for long experience at the High baseline. Fortreum, COACT, Aprio and Earthling Security are strong alternatives for specific needs.
A Third Party Assessment Organization (3PAO) is an independent firm accredited through A2LA to assess cloud services against FedRAMP baselines built on NIST SP 800-53. Its assessment report is what agencies rely on when granting an authorization. FedRAMP has also introduced the 20x pathway alongside the legacy Rev 5 process, so ask assessors which path fits your offering.
Accreditation status can change. Always confirm a firm’s listing on the FedRAMP Marketplace assessor page. If you are earlier in the journey, start with our list of FedRAMP consulting firms, since an advisor and an assessor play different roles.
FedRAMP 3PAOs At A Glance
Assessor
Notable Facts
Best For
Also Offers
Coalfire
Top-three 3PAO by volume, 120+ assessments reported
Enterprises with broad federal scope
Advisory, SOC 2, pen testing
A-LIGN
Describes itself as a top-three 3PAO
Multi-framework audits from one firm
SOC 2, ISO, CMMC
Schellman
One of the initial 3PAOs (2012)
SaaS needing FedRAMP and SOC 2
SOC 2, ISO, GovRAMP
Kratos
Accredited August 2012, assessed to High
High baseline and complex systems
Advisory services
Fortreum
Loudoun County, VA headquarters
Cloud-native and FedRAMP 20x pursuits
Advisory and assessments
COACT
Among the first 12 accredited 3PAOs
Experienced federal assessment teams
Assessment services
Aprio
Accounting firm with a federal assessment practice
Mid-market providers
SOC, GovCon accounting
Earthling Security
Federal cloud security specialist
Smaller cloud providers
Assessment and advisory
The Best FedRAMP 3PAO Assessors In 2027
1. Coalfire — One Of The Busiest 3PAOs In The Program
Coalfire has performed more than 120 FedRAMP assessments by industry counts and runs assessment, advisory and SOC 2 work under one roof.
It suits enterprises with large federal footprints that want an assessor experienced with complex architectures.
2. A-LIGN — High-Volume Assessor For Multi-Framework Programs
A-LIGN describes itself as a top-three FedRAMP 3PAO and supports Rev 5 and FedRAMP 20x along with SOC 2, ISO 27001 and CMMC.
It is a good fit for providers that want several audits coordinated by one firm.
3. Schellman — Initial 3PAO With Strong SOC 2 Practice
Schellman was one of the first accredited 3PAOs in 2012 and also issues SOC 2 reports, with SOC 2 engagements reported from around $20,000.
It works well for govtech SaaS companies selling to both federal and commercial buyers.
4. Kratos — Assessor Since 2012 With FedRAMP High Experience
Kratos was accredited in August 2012, has assessed systems to the FedRAMP High baseline and lists dozens of total assessments on the FedRAMP Marketplace, with clients including major cloud providers.
It suits complex or high-impact systems where assessor experience matters most.
5. Fortreum — Cloud-Focused Assessor Based In Northern Virginia
Fortreum, a cloud computing and cybersecurity firm headquartered in Loudoun County, Virginia, provides FedRAMP assessments and advisory work.
It is a good option for cloud-native providers exploring newer FedRAMP pathways.
Earthling Security focuses on federal cloud security compliance, including FedRAMP and state-level programs.
It can be a responsive option for smaller cloud providers.
How We Evaluated These Assessors
We weighed:
Accreditation history and assessment volume
Experience at Moderate and High baselines
Support for FedRAMP 20x as well as Rev 5
Ability to cover related frameworks such as SOC 2 and GovRAMP
How To Choose A FedRAMP 3PAO
Are you ready for an assessment?
A readiness assessment is useful before the full assessment. Fix gaps with an advisor first.
Which baseline applies?
Low, Moderate and High require very different effort. Choose an assessor with experience at your level.
Can they work on your timeline?
Top assessors book up. Ask about availability and team continuity.
Do you also need SOC 2 or GovRAMP?
Combining audits can save effort. See CMMC vs FedRAMP vs GovRAMP to understand where each framework applies.
Frequently Asked Questions
What is a FedRAMP 3PAO?
A Third Party Assessment Organization is an independent firm accredited through A2LA to assess cloud services against FedRAMP security requirements.
Can my 3PAO also help me prepare?
Independence rules limit how much an assessor can help with the system it assesses. Many providers hire a separate advisor for readiness and remediation.
What is FedRAMP 20x?
FedRAMP 20x is a newer authorization pathway that emphasizes automation and continuous validation, running alongside the legacy Rev 5 process.
How long does a FedRAMP assessment take?
The assessment itself typically takes weeks, but the full authorization journey, including preparation and agency review, often takes many months.
Conclusion
Coalfire, A-LIGN and Schellman are the safest choices for most providers, Kratos for complex High systems, and Fortreum, COACT, Aprio and Earthling Security for teams wanting a closer working relationship. Confirm accreditation on the FedRAMP Marketplace before you sign.
