Operational guidance, not legal advice. This page distills named public sources (regulator guidance and industry practice). It is not a legal determination, not a notification decision, and not a substitute for your counsel, insurer, or a retained DFIR firm. Verify applicability and current deadlines for your facts and jurisdiction.
What are the best SOC 2 audit firms?
Last verifiedWhat are the best SOC 2 audit firms? This page lists major CPA firms by stated criteria, not a ranking. Inclusion is not endorsement. Verify AICPA peer review and CPA licensure. Not legal advice.
Security assurance guidance, last verified 10 September 2026 against AICPA SSAE 18 / AT-C attestation standards, the AICPA Trust Services Criteria, AICPA Code of Professional Conduct ET §1.200 independence rules, and AICPA peer-review programme materials. This page does not rank firms, does not endorse anyone on it, does not determine that SOC 2 applies to YOU, and is not legal advice or procurement advice.
This is an inclusion-criteria checklist, not a ranking
Audience: a founder, CTO, CISO, or compliance lead shortlisting a licensed CPA firm to perform a SOC 2 Type I or Type II examination under AICPA attestation standards. The search query says 'best'; the body is not a quality ranking. Inclusion is a recognition set refreshed on 10 September 2026 — not an endorsement. Rows are alphabetical by current public brand; that order is an index, not a score.
A SOC 2 report is a CPA attestation — not ISO/IEC 27001 certification, not PCI QSA work, not a FedRAMP 3PAO assessment. This page does not determine that SOC 2 applies to YOU. Last verified 10 September 2026. Not legal advice. Not procurement advice.
- Inclusion is not endorsement. A name on this table is not a recommendation to retain that firm.
- CPA licensure and AICPA peer-review status are professional-standard requirements for a valid SOC 2 examination — verify on the current AICPA peer-review roster for the legal entity that would sign YOUR engagement letter.
- UNKNOWN cells mean this page did not verify that authorization for that legal entity — check the current register. UNKNOWN is not a fail and not a pass.
Stated inclusion criteria
A firm belongs on YOUR shortlist only when it meets the criteria that apply to THIS engagement. The table below is stated criteria, not a league table.
| Criterion | What this page records | How to verify | Kind of text |
|---|---|---|---|
| Licensed CPA firm | The legal entity performing the examination holds an active CPA licence in the jurisdiction that governs the engagement. | State board of accountancy register; engagement letter signatory. | Professional standard — AICPA attestation standards require a licensed CPA firm. |
| AICPA peer review | The firm participates in AICPA peer review with an acceptable report for attestation engagements. | AICPA peer-review roster; ask for the current peer-review report summary. | Professional standard — not always a legal mandate, but expected for AICPA members. |
| Independence | No prohibited self-review or advocacy threats under AICPA Code ET §1.200 for YOUR facts. | Independence questionnaire; conflict check before signing. | Professional standard — AICPA Code ET §1.200. |
| Industry experience | The firm publicly describes SOC 2 experience in YOUR sector (SaaS, fintech, healthcare, etc.). | Official SOC 2 service page; reference calls. | Best practice — not a statutory requirement. |
| Price and timeline transparency | The firm publishes or provides a written fee range, timeline, and scope assumptions before signing. | Written proposal; SOW. | Best practice — ShipReadyMetrics recommendation for buyer diligence. |
| Tooling fit | The firm can work with YOUR evidence format (exports, read-only access, control mapping) without requiring a proprietary portal you cannot reuse. | Ask how they consume evidence; whether they accept control-mapped exports. | Best practice — operational fit, not a ranking criterion. |
Criteria table — named CPA firms (alphabetical)
Rows are alphabetical by current public brand after landscape verify on 10 September 2026. That order is not a ranking. Inclusion is not endorsement. Cells are last-verified on this page — check current pages and registers at engagement.
| Current brand | Public SOC 2 offering | CPA / peer review (this page) | Independence note | Scope as they publicly describe it | Last verified |
|---|---|---|---|---|---|
| A-LIGN | Official page describes SOC 2 Type I and Type II attestation examinations. | Not verified on this page — check the current AICPA peer-review roster for the signing legal entity. | Walk ET §1.200 independence questionnaire before signing. | SaaS and technology clients; Type I and Type II. | 10 September 2026 |
| BDO USA | Official page describes SOC 2 attestation services. | Not verified on this page — check the current AICPA peer-review roster. | Walk ET §1.200 independence questionnaire before signing. | Technology and broader sectors; Type I and Type II. | 10 September 2026 |
| Coalfire | Official page describes SOC 2 audit and attestation services. | Not verified on this page — check the current AICPA peer-review roster. | Also offers readiness services — confirm independence before one firm does both. | Cloud, SaaS, and regulated sectors. | 10 September 2026 |
| Deloitte | Official page describes SOC 2 examination services. | Not verified on this page — check the current AICPA peer-review roster for the signing member firm. | Large-firm independence rules apply — walk conflict check. | Global technology and enterprise clients. | 10 September 2026 |
| EY | Official page describes SOC 2 attestation. | Not verified on this page — check the current AICPA peer-review roster. | Large-firm independence rules apply. | Technology and financial services sectors. | 10 September 2026 |
| KPMG | Official page describes SOC 2 reporting services. | Not verified on this page — check the current AICPA peer-review roster. | Large-firm independence rules apply. | Enterprise and technology clients. | 10 September 2026 |
| PwC | Official page describes SOC 2 attestation services. | Not verified on this page — check the current AICPA peer-review roster. | Large-firm independence rules apply. | Technology, financial services, and healthcare. | 10 September 2026 |
| Schellman | Official page describes SOC 2 Type I and Type II examinations. | Not verified on this page — check the current AICPA peer-review roster. | Specialist attestation firm — still walk independence if they also sold readiness. | Technology and cloud-native clients. | 10 September 2026 |
What to do now
The list below is operational preparation. It is not a determination that SOC 2 applies to YOU, that you need Type I versus Type II, or that any firm on this table is right for YOUR engagement. Walk it with counsel and your audit committee if you have one.
- Confirm YOU need a SOC 2 attestation (customer contract, investor ask) — not ISO/IEC 27001 certification, not PCI QSA validation. The SOC 2 framework guide on this site is the education page.
- Shortlist licensed CPA firms only. Consultants who cannot sign an attestation report are a different role — see the auditor-vs-consultant guide on this site.
- Verify AICPA peer-review status and CPA licensure for the signing entity before signing an engagement letter.
- Walk independence: if the same firm sold readiness, confirm ET §1.200 allows the examination — see the same-firm-prepare-and-audit guide on this site.
- Print the questions-before-hiring-an-auditor guide on this site before calls.
Checklist
Selection checklist — not a ranking, not legal advice.
- Licensed CPA firm in the jurisdiction governing the engagement?
- Current AICPA peer-review report with no exceptions for attestation?
- Independence questionnaire clear for YOUR facts (no self-review threat)?
- Trust Services Criteria scope matches what YOUR customers ask for (Security, Availability, etc.)?
- Written timeline and fee assumptions before signing?
- Evidence format agreed (exports, read-only access, control mapping)?
Where this shows up in ShipReady Metrics
ShipReadyMetrics collects control-mapped evidence, runs an evidence-review / met-verdict overlay, and maintains an obligation map (marking a framework in-scope is not a determination that it applies). The 24-framework crosswalk maps to canonical controls with a crosswalk-density honesty layer. Signed-in users can use ShipReady Passport and AI inventory / AI risk register surfaces. This product does NOT issue SOC 2 reports, is NOT a CPA firm, is NOT a certification body, and is NOT legal or audit advice.