Third-party assessment organizations, or “3PAOs,” play a crucial role in compliance with the Federal Risk and Authorization Management Program, more commonly known as FedRAMP.

3PAOs assess the offerings of cloud service providers (CSPs), to help those CSPs satisfy their FedRAMP compliance obligations. Moreover, the 3PAOs’ input allows U.S. federal agencies to make informed, risk-based decisions about the CSPs those agencies might want to use.

This article answers several important questions about 3PAOs. Among them:

  • How do 3PAOs contribute to the FedRAMP authorization process?
  • What are their responsibilities and obligations?
  • What are the requirements for 3PAO accreditation?

Let’s get started.

What Is a FedRAMP 3PAO?

As defined by FedRAMP itself, a FedRAMP 3PAO is “a trusted third party that provides independent assessments with integrity.” This independent party (typically a company rather than an individual person) is authorized to help CSPs meet the requirements for FedRAMP compliance, foremost by assessing the CSP systems for security risks.

The 3PAO must be accredited through the FedRAMP 3PAO program for JAB P-ATO (Joint Authorization Board Provisional Authorization to Operate). 3PAOs must demonstrate independence and the technical competence to test and document a CSP’s security implementations. Authorized and accredited 3PAO assessors are listed on the FedRAMP Marketplace.

Federal agencies can use other independent assessors for FedRAMP security authorizations decisions, but the agency doing so must attest in writing that the assessor is independent and competent. Using an approved 3PAO eliminates the need to provide such attestations.

3PAO: Accreditation Requirements

FedRAMP and the U.S. General Services Administration (GSA) have specific criteria for 3PAO qualification. For example, the assessor must…

  • Meet the International Organization for Standardization (ISO/IEC) 17020 standards for independence and managerial competence.
  • Have technical competence in Federal Information Security Management Act (FISMA) and FedRAMPspecific requirements. (Click here to read more about FedRAMP vs. FISMA.)
  • Demonstrate expertise in assessing cloud-based solutions.

The American Association of Laboratory Accreditors (A2LA) performs the assessment to accredit 3PAOs, based on the accreditation requirements on A2LA provides an assessment report to FedRAMP documenting the 3PAO’s technical competence and experience in inspecting CSP systems.

The report also states whether the 3PAO has a documented and fully operational quality management system (QMS) and whether the organization operates according to this QMS.

3PAO Roles and Responsibilities

A 3PAO evaluates a CSP from a security and risk perspective. It verifies the vendor’s security implementations, compares them against the controls specified in FedRAMP, and confirms whether the implementations match the controls requirements. The 3PAO also reviews the documents (formally known as “artifacts”) of a CSP’s security authorization package in accordance with FedRAMP requirements

Finally, the assessor considers the overall risk posture of the vendor’s cloud environment, to guide the security authorization decision of a federal agency or the FedRAMP JAB.

The 3PAO plays a role at various stages of the CSP assessment and authorization process:

  • Readiness assessment. The assessor prepares the readiness assessment report (RAR) and submits it to the FedRAMP PMO.
  • Full security assessment. The 3PAO performs an in-depth review of the CSP’s system security plan (SSP) for FedRAMP compliance and creates a security assessment plan (SAP) and security assessment report (SAR) with matching test cases. It also works with the CSP to develop a plan of action and milestones (PoAM).
  • Authorization process. The assessor highlights risks in a cloud service offering (CSO), performs any required retests, and updates all security documentation based on comments from JAB reviewers.

3PAO Obligations

All 3PAOs and their assessments must adhere to FedRAMP requirements for quality, accuracy, integrity, and timeliness. They must also maintain accreditation by demonstrating that they operate in accordance with ISO/IEC 17020 and FedRAMP requirements.

The 3PAO must be independent of the CSP it is assessing, so that the assessor can submit an opinion about the CSP’s security posture without influence from the CSP.

Finally, every 3PAO must develop an employee training program with content incorporating FISMA, FedRAMP, cloud computing, and cybersecurity.

Important Documents Created by a 3PAO

When assessing the security of a CSO, the 3PAO creates numerous documents. These are explained below.

Readiness Assessment Report (RAR)

During the CSP assessment and authorization process, 3PAOs produce a RAR. They may also provide a complete security authorization package consisting of an SAP and SAR. (We will explain the SAP and SAR in more detail below.)

RAR is part of the first phase of the CSP assessment. During this phase, the 3PAO completes the readiness assessment, prepares the RAR, and submits it to the FedRAMP PMO. The assessor also provides support to the FedRAMP project management office during the RAR review.

Security Assessment Plan (SAP)

The 3PAO creates an SAP during the full security assessment of the CSP. For this, the assessor uses a FedRAMP SAP template available on

In this phase, the assessor assures that all documentation within the SSP matches security control implementations and supports the FedRAMP PMO’s completeness checks.

The SAP identifies the various assets within the scope of the assessment, including hardware, software, and physical facilities

It also provides a methodology and rules of engagement to execute the security tests when assessing a CSO for FedRAMP compliance. The baseline test cases are available on

The 3PAO can also create alternative test cases for the alternative implementation of controls in the SSP. These are meant to test the effectiveness of the CSP’s controls and to identify the risks that may arise with the implementation of these controls.

During testing, the CSP creates a plan to coordinate the 3PAO’s site visits and personnel interviews. The CSP will also define a schedule of when scans will be performed on the system.

Security Assessment Report (SAR)

After testing the CSP’s security controls, the 3PAO analyzes the risks in the provider’s cloud environment and presents the results in a security assessment report (SAR). This document contains information about the vulnerabilities, threats, and risks discovered during testing.

The SAR also contains guidance to help CSPs mitigate these security weaknesses. The report is first delivered to the CSP and then to the federal agency’s security team. This team will analyze the SAR to determine the CSO’s risk posture.

In general, a 3PAO’s SAR contains these artifacts:

  • Security assessment test case workbook
  • Risk exposure table
  • Penetration test report
  • Vulnerability scan data files
  • Test artifacts

Like the SAP, the 3PAO uses a template for the SAR available on

Per FedRAMP rules, all these documents must be based on the most recent standard templates. They must also:

  • Be complete on the first submission.
  • Meet the quality standards published in the FedRAMP General Document Acceptance Criteria guidance.
  • Be delivered per the schedule agreed upon by the CSP, agency, and 3PAO.
  • Assure testing of the CSO in accordance with ISO/IEC 17020.

Choosing a 3PAO: Checklist for Cloud Service Providers

CSPs must also be careful about choosing a 3PAO as they pursue FedRAMP certification. To make the right choice, the service provider must ask crucial questions such as:

  • How many FedRAMP security assessments has the 3PAO previously completed?
  • Has the 3PAO worked with this federal agency (the agency the CSP wants to work with) before?
  • Is the 3PAO familiar with the agency’s assessment processes and procedures?
  • Is its assessment team experienced with both auditing and IT systems management and engineering?
  • Does the 3PAO perform a gap assessment before technical analysis and penetration testing of the CSP’s cloud environment?

A 3PAO that ticks off all these requirements can be hugely beneficial for a CSP.

An experienced 3PAO can significantly ease the burden of preparing the SSP and PoAM. The assessor can perform a gap assessment to identify existing shortfalls in the CSP’s processes, documentation, or technology; and can guide changes the  CSP will need to make to meet FedRAMP compliance requirements.


Cost of 3PAO FedRAMP

The cost of 3PAO assessments can vary significantly based on numerous factors. Here’s a breakdown of the typical costs associated with obtaining a FedRAMP authority-to-operate (ATO):

  • Security assessment report (SAR). The cost ranges from $125,000 to $190,000, depending on the 3PAO​​.
  • 3PAO assessment. The average cost for a 3PAO assessment is around $500,000​​.
  • Additional costs. Engaging a 3PAO for testing and execution of the test plan can cost in excess of $150,000​​.
  • Overall budget. Organizations may need to budget anywhere from $250,000 to $750,000 to pursue FedRAMP certification​​.

Approval or Recognition of 3PAOs

3PAOs are recognized by the FedRAMP Program Management Office (PMO) but are required to be accredited by A2LA (American Association for Laboratory Accreditation). To gain this recognition, the assessor must do two things.

  • Accreditation. Organizations must spend at least a year in the Cybersecurity Inspection Body Program demonstrating technical competence before consideration for FedRAMP 3PAO recognition.
  • Program requirements. The 3PAO must adhere to various international standards and requirements, including ISO/IEC 17020 and specific FedRAMP requirements​​.

The Process for 3PAOs to Be Certified

Broadly speaking, a 3PAO must pass three tests to be certified as suitable for FedRAMP compliance.

  • Technical proficiency testing. A real-time assessment of a simulated cloud environment is conducted. Teams review system security plans and assess a subset of security controls.
  • Evaluation of technical competence. 3PAOs undergo a rigorous evaluation of their technical skills and compliance with international standards.
  • Continuous partnership. A2LA works with BCR Cyber to provide proficiency testing for 3PAOs. The entire process is managed and streamlined to assure efficiency​​.

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