12 Red Flags When Choosing a SOC2 Auditor

This is disqualifying. Only licensed CPA firms can issue SOC2 attestation reports under AICPA AT-C Section 205. If a vendor can't provide their CPA firm name, state license number, and license status — do not engage them. Cybersecurity consultants, vCISOs, and pen test firms can help you prepare but cannot issue the final report.

AICPA requires CPA firms that perform attestation engagements to undergo peer review every three years. Ask directly: 'What is your firm's most recent peer review result?' A firm that cannot provide this is either not AICPA-enrolled, has a failing review, or is being evasive. Many enterprise buyers will reject a report from a firm without a clean peer review.

A SOC2 Type 2 quote of $4,000-$8,000 is a red flag. Legitimate SOC2 Type 2 engagements have a minimum floor of $12,000-$15,000 even for tiny startups. Prices this low typically mean the scope has been stripped to near nothing, the observation period is artificially short, junior staff will run the whole engagement, or the firm lacks experience and is underpricing to get the work.

A qualified SOC2 auditor should be able to tell you, before signing: which specific CC criteria they will test, what evidence they will need, how they will handle your specific tech stack (AWS/GCP/Azure), and what a typical audit finding looks like. Vague answers about 'reviewing your environment' indicate lack of SOC2-specific experience.

Some firms quote low by assigning the bulk of the work to junior associates with 1-2 years of SOC2 experience. Ask directly: 'Who will be the primary contact for our engagement, and what is their SOC2 experience level?' A qualified engagement should have a senior manager or partner involved in planning, evidence review, and all client-facing decisions — not just signing the final report.

If you use AWS, Azure, GCP, Vanta, or Drata and the auditor has never worked with these, expect friction. Auditors unfamiliar with your environment will ask for more evidence, take longer to verify configurations, and may miss cloud-native controls that satisfy multiple criteria simultaneously. Ask for references from companies with similar stacks.

A competent SOC2 auditor should be able to provide 2-3 client references in your vertical or company stage. Healthcare SaaS, fintech, and govtech have specific control considerations that generalist CPA firms may not understand. If references are unavailable or all from different industries, that's a meaningful data point.

Before signing an engagement letter, you should receive a written document that clearly defines: the audit period, the in-scope systems, the Trust Services Criteria being assessed, what is explicitly excluded, the deliverables, and the payment terms. Any firm unwilling to provide this is a significant contractual risk.

The AICPA requires a minimum observation period for SOC2 Type 2 engagements. Any firm claiming to complete Type 2 in 3-4 months is either shortcutting the observation period or misrepresenting the engagement type. Legitimate Type 2 minimums are 8-9 months total (6-month observation + pre/post-work). A suspicious timeline claim that sounds too good should prompt hard questions.

Some auditors also offer readiness assessment, control implementation, and policy writing services. While this is not automatically disqualifying, the AICPA independence rules prohibit auditors from auditing controls they helped implement. Ask: 'Does your firm maintain full independence from the readiness/consulting work if we hire you for both?' A trustworthy firm will have a clear policy; evasiveness is a red flag.

Professional SOC2 auditors use structured evidence request lists (typically delivered via a shared portal or GRC platform integration). If your auditor plans to collect evidence via email threads and spreadsheets with no formal process, expect miscommunication, missing evidence, and prolonged audit timelines. Ask to see their evidence collection template before signing.

If you receive exceptions or observations in the final report, your auditor should be able to explain them clearly to your engineering team, your board, and your customers. Auditors who communicate only in AICPA jargon and cannot translate findings into actionable language will create downstream problems when you're presenting the report to enterprise buyers.