The 12 Best ISO 27001 Auditors in 2026
Ranked by real buyer interest on ISMS Directory over the last 30 days. Updated September 2026.
1. DNV
Global assurance provider offering ISO 27001 certification and risk-based management system audits, with deep Nordic and critical-infrastructure roots.
- ISO 27001
- ISO 22301
- ISO 9001
- Multi-framework
- SOC 2
2. BSI
Global standards body and UKAS-accredited certification organization for ISO 27001, privacy, AI management, and related management systems, plus training.
- ISO 27001
- ISO 27701
- ISO 42001
- ISO 22301
- ISO 9001
- Multi-framework
3. I.S. Partners
Philadelphia CPA and compliance firm for SOC, HIPAA, HITRUST, PCI, and ISO 27001 assessments.
- ISO 27001
- SOC 2
- SOC 1
- HIPAA
- HITRUST
- PCI DSS
4. Schellman
Leading US IT compliance attestation firm for SOC 1/2/3, PCI, and ANAB-accredited ISO certifications including ISO 27001 and ISO 42001.
- ISO 27001
- SOC 2
- SOC 1
- ISO 42001
- ISO 27701
- ISO 22301
5. Johanson Group LLP
Boutique US CPA firm specializing in SOC 1/2/3 examinations and related security and compliance audits for growing companies.
- ISO 27001
- SOC 2
- SOC 1
- HIPAA
- Multi-framework
- CCPA
6. Amtivo
International ISO certification group (including former Certification Europe) offering INAB-accredited ISO 27001 certification and training.
- ISO 27001
- ISO 9001
- ISO 22301
- ISO 45001
- Multi-framework
- Cyber Essentials
7. Coalfire
Enterprise cybersecurity and compliance assessment firm for FedRAMP, SOC 2, HITRUST, PCI, ISO 27001, and government frameworks.
- ISO 27001
- SOC 2
- FedRAMP
- HITRUST
- PCI DSS
- CMMC
8. Sensiba
Bay Area CPA firm with a technology assurance practice for SOC 2 and related reports.
- ISO 27001
- SOC 2
- SOC 1
- Multi-framework
- CMMC
- CSA STAR
9. BARR Advisory
Cloud-native compliance firm offering SOC 2 audits and ISO 27001 certification with coordinated multi-framework programs for SaaS.
- ISO 27001
- SOC 2
- FedRAMP
- HITRUST
- CMMC
- PCI DSS
10. SGS
World-leading inspection, verification, and certification company offering ISO 27001 and multi-standard management system certification.
- ISO 27001
- ISO 9001
- ISO 22301
- Multi-framework
11. Bureau Veritas
French-rooted global certification and inspection leader providing ISO 27001 and related management system certification.
- ISO 27001
- ISO 9001
- ISO 22301
- Multi-framework
12. AENOR
Leading Spanish certification body for ISO 27001, ENS (Spanish National Security Scheme), and multi-standard management systems.
- ISO 27001
- ISO 9001
- ISO 22301
- Multi-framework
Compare at a glance
| Rank | Provider | Listed frameworks | Listed regions | Profile |
|---|---|---|---|---|
| 1 | DNV | ISO 27001, ISO 22301, ISO 9001, Multi-framework, SOC 2 | Global, Europe, Norway +6 more | View profile |
| 2 | BSI | ISO 27001, ISO 27701, ISO 42001, ISO 22301, ISO 9001, Multi-framework | Global, Europe, United Kingdom +1 more | View profile |
| 3 | I.S. Partners | ISO 27001, SOC 2, SOC 1, HIPAA, HITRUST, PCI DSS | United States, Global | View profile |
| 4 | Schellman | ISO 27001, SOC 2, SOC 1, ISO 42001, ISO 27701, ISO 22301 | United States, Global, Europe +1 more | View profile |
| 5 | Johanson Group LLP | ISO 27001, SOC 2, SOC 1, HIPAA, Multi-framework, CCPA | United States, Global | View profile |
| 6 | Amtivo | ISO 27001, ISO 9001, ISO 22301, ISO 45001, Multi-framework, Cyber Essentials | Ireland, United Kingdom, United States +2 more | View profile |
| 7 | Coalfire | ISO 27001, SOC 2, FedRAMP, HITRUST, PCI DSS, CMMC | United States, Global, United Kingdom +1 more | View profile |
| 8 | Sensiba | ISO 27001, SOC 2, SOC 1, Multi-framework, CMMC, CSA STAR | United States | View profile |
| 9 | BARR Advisory | ISO 27001, SOC 2, FedRAMP, HITRUST, CMMC, PCI DSS | United States, Global | View profile |
| 10 | SGS | ISO 27001, ISO 9001, ISO 22301, Multi-framework | Global, Europe, Asia +4 more | View profile |
| 11 | Bureau Veritas | ISO 27001, ISO 9001, ISO 22301, Multi-framework | Global, Europe, France +6 more | View profile |
| 12 | AENOR | ISO 27001, ISO 9001, ISO 22301, Multi-framework | Spain, Europe, Latin America | View profile |
Frequently asked questions
- How is this ISO 27001 Auditors ranking determined?
- Providers are first filtered to those that substantively cover ISO 27001 Auditors in the ISMS Directory catalogue, then ordered by real buyer interest — the directory traffic and engagement each provider received over the last 30 days. It is not paid placement and it is not an editorial opinion.
- How often is the list updated?
- The ranking recomputes from live directory-demand data on a rolling 30-day window and refreshes roughly every 15 minutes, so it reflects current interest rather than a one-off 2026 snapshot.
- Why are only 12 providers shown?
- This list shows the top providers by demand for ISO 27001 Auditors. Pages with fewer than three substantively-matching providers are not published at all, so every entry here represents a real, comparable option.
- How can my company appear here?
- Get listed in ISMS Directory with ISO 27001 Auditors expertise. Ranking is earned through genuine directory demand — there is no way to pay for a position.