Insight Assurance vs. Schellman: Comparing Audit Firms

Insight Assurance and Schellman both perform independent audit and assessment work across major security and compliance frameworks, including SOC examinations, ISO/IEC certification audits, PCI DSS, HITRUST, FedRAMP, CMMC, and cybersecurity testing. Their core framework coverage overlaps; the differences show up in credentials, multi-framework and federal coordination, pricing, and the team that carries the engagement from scope through reporting.

Insight Assurance is a licensed CPA firm, a PCI Qualified Security Assessor (QSA), a HITRUST Authorized External Assessor, an authorized CMMC Third-Party Assessment Organization (C3PAO), and a FedRAMP-recognized independent assessor (formerly 3PAO). ISO/IEC certification work runs through IA Certifications. 

Insight Assurance is accredited by the International Accreditation Service (IAS), an IAF MLA signatory, for ISO/IEC 27001, 27701, and 42001. Founded by former Big 4 professionals, the firm serves 2,500+ clients across North America, South America, Europe, and APAC and is expanding in the GCC.

Schellman is also a CPA firm and holds PCI QSA, HITRUST, CMMC, FedRAMP, and ISO/IEC certification credentials, including certification-body accreditation from ANAB and UKAS. It calls its multi-assessment model the Power of One.

Credentials and Framework Coverage at a Glance

That overlap does not make the services interchangeable. A SOC examination, PCI DSS assessment, HITRUST assessment, ISO/IEC certification audit, and penetration test follow different requirements and may call for different qualifications or specialists. When several are in scope, coordination has to preserve the requirements of each engagement.

Federal Assessments Call for Specific Credentials

FedRAMP’s 2026 rules refer to recognized third-party assessment organizations as Independent Assessors, formerly 3PAOs. CMMC Level 2 certification assessments require authorized C3PAOs. Insight Assurance and Schellman hold both types of assessment credentials.

FedRAMP work reaches beyond an initial assessment. Cloud architecture, technical testing, evidence, and continuous monitoring can all affect the engagement, so the experience of the assessors assigned to a particular authorization path matters. Ask whether the assigned assessors are currently recognized, familiar with comparable environments, and available for ongoing assessment work.

Power of One and InsightONE Tackle the Same Problem

Running SOC 2, ISO/IEC 27001, and PCI DSS in the same year can produce overlapping evidence requests. Schellman’s Power of One and InsightONE both coordinate schedules and evidence across engagements so teams can identify legitimate reuse without collapsing separate framework requirements.

Each framework keeps its own criteria, testing, and report. A SOC 2 examination is an attestation under AICPA standards, while ISO/IEC 27001 certification evaluates an information security management system against the standard. InsightONE is a delivery methodology, not software, and is designed to work alongside an organization’s existing compliance platform.

What Clients Say About Working With Insight Assurance

Insight Assurance holds a 4.9 out of 5 rating across more than 140 G2 reviews and earned Fall 2026 G2 Leader badges in IT Compliance Services and Penetration Testing Services. It also ranked No. 820 on the 2026 Inc. 5000, its second consecutive year on the list after placing No. 399 in 2025

G2 reviewers point to responsiveness and communication during the engagement. One wrote that the team was “consistently quick to respond throughout the engagement” and highlighted “communicating and collaborating with us directly in Slack.” London-based SaaS company Hook described its engagement as “a very seamless process in terms of the discovery and scoping.”

Advanced Logic Completes a Second Consecutive SOC 2 Type II

Advanced Logic, a managed IT and information security services provider in Blacksburg, Virginia, relies on independent validation to maintain customer and partner trust. For its second SOC 2 Type II examination, it wanted a thorough process grounded in its own environment and risk profile without turning the examination into a disruptive project for its security team.

Rather than starting with a generic checklist, the audit team learned the environment first. Advanced Logic credited the team’s “responsiveness and collaborative, solution-oriented mindset” and said its auditors “clarify complex compliance requirements.”

Advanced Logic completed the examination with limited disruption to daily operations. Dave Cropco, Vice President of Information Security, summed up the result: “Insight Assurance doesn’t just deliver audit reports — they bring clarity and consistency to the process, helping our team navigate the SOC 2 examination with confidence.”

Read the Advanced Logic case study.

ServiceRocket Adds an ISO/IEC 27001 Perspective

ServiceRocket, a technology services company with staff across multiple time zones, pursued its first ISO/IEC 27001 certification and needed clear expectations around audit stages, evidence, and internal-auditor qualifications. Insight Assurance selected a lead auditor with time-zone accessibility in mind and debriefed the team after each audit day through Stage 1 and Stage 2. ServiceRocket completed certification, remediated its nonconformities without major issues, and planned the full three-year certification cycle with fixed pricing. Catherine Matterson said the company “could not have been happier with the outcome.”

Read the ServiceRocket case study.

Continuity Carries Over From One Cycle to the Next

Recurring SOC 2 and ISO/IEC work brings prior findings, control history, and environmental changes back into scope. A returning team can reduce the amount of context that has to be rebuilt. One G2 reviewer praised the auditors’ “deep understanding of our product and environment, which is valuable for future audits.”

Insight Assurance was founded by former Big 4 auditors and emphasizes an auditor-led relationship. Ask either firm who will lead the work, which specialists will participate, and how assignments carry over between cycles.

How Each Firm Structures Pricing

Schellman describes its pricing as outcome-based and fixed-fee once scope is established. Insight Assurance uses custom-scoped pricing based on the frameworks, systems, and testing required for each engagement

Compare proposals against the same systems and entities in scope, testing requirements, deliverables, separately priced work such as penetration testing, and the conditions that would trigger a change in fees or scope.

Compare the Delivery Model Against Your Roadmap

Both firms can support commercial and federal compliance programs. Schellman’s Power of One model coordinates multiple assessments through one provider, while InsightONE coordinates work alongside an organization’s existing compliance tools. For organizations with several frameworks on the roadmap, the practical differences show up in how evidence is coordinated, which specialists stay involved, and how much context carries forward between cycles.

Learn more about Insight Assurance or Contact Us to discuss your security and compliance requirements.

FAQ

Is Insight Assurance or Schellman Better for SOC 2?

Both firms perform SOC 2 examinations under AICPA attestation standards. Compare the assigned team’s SOC experience, evidence workflow, continuity, and the frameworks likely to follow.

What Are Alternatives to Schellman?

Insight Assurance is one alternative, with licensed CPA, PCI QSA, HITRUST, CMMC, FedRAMP independent assessment, and ISO/IEC certification credentials. See Insight Assurance vs. A-LIGN and Insight Assurance vs. Prescient Security for more comparisons.

How Should Buyers Compare Insight Assurance and Schellman Pricing?

Insight Assurance uses custom-scoped pricing based on the frameworks, systems, and testing required for each engagement. Schellman describes its pricing as outcome-based and fixed-fee once scope is established. Compare equivalent systems and entities in scope, testing requirements, deliverables, and separately priced work before comparing fees.

How Do Power of One and InsightONE Differ?

Schellman’s Power of One coordinates teams, schedules, and evidence across multiple assessments through one provider. InsightONE is an audit-delivery methodology designed to coordinate work across frameworks alongside an organization’s existing compliance tools.

See Insight Assurance vs. A-LIGN and Insight Assurance vs. Prescient Security for more comparisons.