How to Choose a SOC 2 Auditor

Required Qualifications

SOC 2 audits are attestation engagements governed by AICPA professional standards (SSAE 18). Not every accounting firm — and no non-CPA firm — is qualified to perform them. Before engaging any firm, verify two non-negotiable qualifications:

• Licensed CPA firm — The firm must hold a valid CPA license issued by a state board of accountancy. Only licensed CPA firms can issue SOC 2 reports under AICPA standards. Non-CPA security consultants, compliance platforms, and IT audit firms cannot issue SOC 2 reports, regardless of their technical expertise.
• AICPA Peer Review enrollment — Firms performing SOC 2 engagements must be enrolled in the AICPA Peer Review program. Peer review is an independent quality assessment conducted by other CPA firms to ensure audit practices meet professional standards. A firm's peer review status is publicly searchable through the AICPA's online database.

Beyond these baseline requirements, look for firms with dedicated SOC practice groups, experienced engagement leads (not just junior staff), and demonstrated expertise in your industry and technology environment.

Compare the proposed engagement team

Firm size alone does not establish audit quality, price or delivery speed. Compare the named engagement lead’s relevant experience, the proposed scope, independence, evidence process, fee inclusions and availability. Confirm any buyer-specific requirements before selecting a firm. Ask each candidate for comparable references and the applicable professional verification records.

10 Questions to Ask a SOC 2 Auditor

Before signing an engagement letter, ask these questions to evaluate fit and quality:

1. How many SOC 2 engagements does your firm complete annually? — Volume indicates experience and established methodology.
2. Who will lead my engagement, and what is their SOC experience? — Ensure a senior, experienced auditor is assigned, not just junior staff.
3. Do you have experience with my industry and technology stack? — Auditors familiar with your environment scope more efficiently and ask better questions.
4. What is your current AICPA Peer Review status? — Confirm enrollment and check for any findings or deficiencies.
5. How do you handle mid-engagement scope changes? — Understand the process and cost implications if scope needs to adjust.
6. What is your communication cadence during the audit? — Establish expectations for status updates, questions, and issue resolution.
7. Can you provide references from clients in my industry? — Speak with current clients about their experience.
8. What is included in your fee, and what costs extra? — Clarify whether readiness assessments, remediation guidance, and report revisions are included.
9. How do you deliver audit requests and track evidence? — Efficient firms use structured request lists and secure portals, not endless email chains.
10. What is your typical timeline from kickoff to report delivery? — Understand the expected timeline and factors that could extend it.

Red Flags to Avoid

Not all CPA firms deliver the same quality. Watch for these warning signs when evaluating potential auditors:

• No AICPA Peer Review enrollment — This is a mandatory requirement. If a firm is not enrolled, they should not be performing SOC 2 audits. Walk away.
• Firm size alone does not establish audit quality, price or delivery speed. Compare the named engagement lead’s relevant experience, the proposed scope, independence, evidence process, fee inclusions and availability. Confirm any buyer-specific requirements before selecting a firm. Ask each candidate for comparable references and the applicable professional verification records.
• Unclear or variable pricing — Reputable firms provide clear, fixed-fee proposals. If pricing is vague, subject to significant "additional fees," or changes after the engagement begins, it signals poor scoping or intentional underquoting.
• No industry experience — A firm that has never audited a company like yours will take longer, ask unnecessary questions, and may scope the audit incorrectly.
• Reluctance to provide references — Quality firms are proud of their client relationships. If a firm cannot or will not provide references, consider it a red flag.
• Promising guaranteed outcomes — No reputable auditor guarantees an unqualified opinion before examining your controls. If a firm promises a clean report regardless of findings, their independence is compromised.

Why Auditsuisse

Auditsuisse is a licensed CPA firm enrolled in the AICPA Peer Review program, with dedicated SOC practice groups staffed by senior auditors. We specialize in SOC 2 for technology companies, SaaS platforms, and high-growth startups. Every engagement is led by experienced professionals who understand cloud-native architectures, modern engineering practices, and enterprise procurement requirements.

We believe the auditor-client relationship should be a partnership. Our clients get direct access to their engagement lead, clear and fixed pricing, structured communication throughout the audit, and actionable recommendations that improve their control environment — not just a report.

"The auditor-client relationship is a partnership, not a transaction. The right firm brings industry expertise, clear communication, and a genuine interest in helping you improve your control environment — not just checking boxes."

— Sébastien Ruosch, CPA, Director of Auditsuisse Assurance