Uncategorized

SOC 2 vs ISO 27001: When You Need Both, Mapping Controls, Cost Comparison

By chrisomo

SOC 2 vs ISO 27001 is the most common compliance question for B2B SaaS companies selling globally. SOC 2 is a US-originated attestation engagement against the AICPA Trust Services Criteria. ISO 27001 is an internationally recognized certification of an Information Security Management System against ISO/IEC 27001:2022 Annex A’s 93 controls.

The short version

Pick SOC 2 if you sell to US customers and procurement teams expect it. Pick ISO 27001 if you sell to European, Asian, or regulated-industry customers and procurement frameworks treat ISO certification as the baseline. Pick both if your buyer base spans both regions or if you sell into financial services and healthcare where the comfort of dual coverage is worth the marginal cost.

What SOC 2 does

SOC 2 is an attestation engagement under AICPA SSAE 18 AT-C 105 and AT-C 205, reporting against the AICPA Trust Services Criteria (TSP Section 100). The security category is mandatory. Availability, processing integrity, confidentiality, and privacy are optional categories that the service organization can include based on customer demand.

The deliverable is an opinion letter from a licensed CPA firm describing the service organization’s control environment and the auditor’s opinion on whether the controls were suitably designed (Type 1) and operating effectively over the observation period (Type 2). The report itself runs anywhere from 60 to 250 pages, with the bulk being the system description, control matrix, and test results section.

SOC 2 is principle-based rather than prescriptive. Two service organizations can both achieve clean SOC 2 opinions with very different control populations as long as each control population maps to the Trust Services Criteria. This flexibility is a feature for the service organization and a frustration for the reader, who has to evaluate the control set itself rather than just the opinion.

Procurement teams in the US have effectively standardized on SOC 2 Type 2 as the baseline B2B SaaS trust deliverable. Enterprise procurement teams at companies like Salesforce, ServiceNow, and Workday treat the absence of a SOC 2 Type 2 as a hard block on enterprise contracts above a certain size threshold.

The 2017 Trust Services Criteria update is worth understanding because it determines what the auditor actually tests against. The TSC is organized into nine common criteria (CC1 through CC9) covering control environment, communication, risk assessment, monitoring, control activities, logical and physical access, system operations, change management, and risk mitigation. Each common criterion has multiple points of focus. The auditor selects controls at the service organization that map to each criterion and tests those controls. Different service organizations achieve the same SOC 2 opinion with very different control populations.

What ISO 27001 does

ISO/IEC 27001:2022 is an international standard for an Information Security Management System (ISMS). Certification is issued by an accredited certification body (BSI, Schellman ISO, A-LIGN ISO, DNV, TUV, Bureau Veritas) following a two-stage audit. Stage 1 is a documentation review and readiness check. Stage 2 is the on-site (or remote) audit that produces the certification recommendation.

The ISO 27001 controls are organized in Annex A of the standard. The 2022 revision (replacing the 2013 version) consolidated the control list from 114 to 93 controls, grouped into four themes: organizational (37 controls), people (8), physical (14), and technological (34). The controls are prescriptive enough that two certified organizations look more similar than two SOC 2 organizations do.

The certification has a three-year cycle. Year 0 is the Stage 1 + Stage 2 initial audit. Years 1 and 2 are surveillance audits at roughly 30 to 50 percent of the original Stage 2 scope. Year 3 is the recertification audit, which is essentially a full Stage 2 rerun. Surveillance failures or non-conformities flagged during any year of the cycle can suspend the certification.

ISO 27001 is the global procurement baseline outside the US. European data-protection regulators reference it explicitly in GDPR guidance. UK Government Cyber Essentials Plus, the Australian Information Security Manual, and the Japanese ISMS framework all map cleanly to ISO 27001. Procurement frameworks in financial services (DORA, Basel) treat ISO certification as a baseline assurance signal.

The 2022 revision of ISO 27001 is the current standard. Companies certified under ISO 27001:2013 had a transition window through October 2025 to migrate to the 2022 version; certificates against the 2013 standard are now expired. The 2022 revision introduced 11 new controls (notably threat intelligence, ICT readiness for business continuity, data leakage prevention, web filtering, and secure coding) and consolidated several 2013 controls. Organizations evaluating ISO 27001 in 2026 are universally evaluating the 2022 version.

The ISMS clauses (clauses 4 through 10 of the ISO 27001 standard text, separate from the Annex A controls) are what differentiate an ISO 27001 implementation from a SOC 2 implementation operationally. The clauses require: defined ISMS scope, formal risk assessment and treatment methodology, Statement of Applicability documenting which Annex A controls apply, internal audit program, management review, corrective action process, and continual improvement cycle. These management-system mechanics are what produce the “continuous improvement” pattern that ISO 27001 is known for.

Side-by-side comparison table

Which fits your situation

SOC 2 only. US-headquartered B2B SaaS selling primarily into US customers. Mid-market buyer base. Procurement teams ask for SOC 2 Type 2 by name in vendor questionnaires. Limited regulated-industry exposure. Series A or Series B stage with limited compliance budget. This is the default profile for the bulk of the US SaaS startup ecosystem.

ISO 27001 only. European or Asia-Pacific headquartered company. Selling into EU public-sector or financial-services accounts. Customer base includes large industrial enterprises (manufacturing, telecom, utilities) where ISO certification is the procurement baseline. Going through a tender process that explicitly requires ISO certification. Lighter US enterprise exposure.

Both. Global buyer base. Selling into both US and EU enterprise accounts. Customer base includes regulated industries (financial services, healthcare, government contractors) where dual coverage signals maturity. Annual revenue above $20M ARR where the marginal cost of the second program is a small fraction of the deal-flow risk it offsets. Most public SaaS companies above $100M ARR carry both because the procurement-question-cost of carrying only one exceeds the compliance-program cost of carrying both.

Use our internal controls testing primer to evaluate the readiness gap before you commit to either path. The cost-of-readiness work is highly similar across both programs, which is why running them together is materially more efficient than running them sequentially.

Control mapping in practice

The overlap between SOC 2 (security category) and ISO 27001:2022 Annex A is meaningful but not complete. Organizations running both programs typically build a unified control catalog that maps each control to both frameworks, with framework-specific evidence templates layered on top. The mapping itself is published by both AICPA and ISO; the operational work is in producing evidence that satisfies both auditors.

Access controls, change management, vulnerability management, incident response, vendor management, and physical security all map cleanly across the two frameworks. The areas with less clean mapping are ISMS-specific (the management review cycle, the corrective action process, the Statement of Applicability) and SOC 2-specific (the system description, the points-of-focus methodology). These are run as framework-specific workstreams within the unified program.

Companies running unified compliance programs typically use a GRC tool (Vanta, Drata, Secureframe, Hyperproof, OneTrust) to maintain the control catalog and the evidence base. The leading GRC tools all support both SOC 2 and ISO 27001 mapping out of the box, which materially reduces the labor cost of running both programs.

Cost comparison

The first-year cost comparison underestimates ISO 27001 if you only look at audit fees, because ISO 27001 has a three-year cycle that includes surveillance audits and a recertification audit. The first-year cost comparison overestimates SOC 2 if you ignore the readiness consulting and GRC tooling that go into a clean first-year Type 2.

SOC 2 Type 2, mid-market first year. Audit fee $40K to $150K. Readiness consulting $30K to $80K. GRC tooling $15K to $50K. Internal labor (employee time on evidence collection, policy authoring, control remediation) $80K to $200K. Total first-year TCO $165K to $480K, with a steady-state of $80K to $200K annually thereafter.

ISO 27001, mid-market first year. Stage 1 + Stage 2 audit fee $30K to $80K. ISMS readiness consulting $25K to $70K. GRC tooling $15K to $50K (same tools, often reused from SOC 2). Internal labor $70K to $180K. Total first-year TCO $140K to $380K. Years 2 and 3 surveillance audits run $15K to $40K each. Year 3 recertification adds another $30K to $80K.

Both programs concurrently. The shared infrastructure (policies, evidence, risk register, ISMS scope) means the dual-program first-year cost is typically 1.4x to 1.7x of a single SOC 2 program, not 2x. The audit fees do not discount, but everything upstream of the audit does. Vanta, Drata, and Secureframe all publish dual-program TCO benchmarks showing 30 to 40 percent labor savings versus running the programs sequentially.

The single biggest cost driver for both programs is not the audit fee; it is internal labor. Companies that automate evidence collection with GRC tooling cut internal labor by 40 to 60 percent compared to spreadsheet-driven evidence management.

Common mistakes when choosing

Picking SOC 2 because it’s cheaper, then losing EU enterprise deals. SOC 2 carries weak recognition with European procurement frameworks. A vendor pursuing EU enterprise accounts who only carries SOC 2 routinely gets the follow-up question “do you also have ISO 27001?” and loses the deal velocity advantage. If 30+ percent of pipeline is EU, the ISO investment pays for itself in two to three closed deals.

Picking ISO 27001 because it’s “international,” then failing US procurement. Mirror problem. US enterprise procurement teams (Workday, ServiceNow, Salesforce all behave this way) treat SOC 2 Type 2 as the procurement baseline and ISO 27001 as an additional positive signal but not a substitute. If your customer base is US-heavy, leading with ISO 27001 alone is a procurement-velocity mistake.

Running the programs sequentially. The readiness work overlaps 60 to 70 percent. Running ISO 27001 a year after SOC 2 (or vice versa) means re-doing the policy work, re-collecting overlapping evidence, and re-coordinating the same control owners. Dual-program planning from day one cuts total cost meaningfully.

Scoping ISO 27001 to “exclude” too much. The ISO Statement of Applicability lets you exclude Annex A controls with documented justification. Aggressive exclusion shrinks audit cost but produces a thin certificate that procurement teams correctly read as evasive. The Statement of Applicability is itself a procurement-read document; if it excludes a third of Annex A, that becomes the procurement question.

Treating either program as a one-time project. Both SOC 2 and ISO 27001 are continuous programs. SOC 2 has annual Type 2 cycles with rolling observation periods; ISO has three-year cycles with annual surveillance. Companies that treat the first-year certification as the finish line invariably hit surveillance failures in year two. Build the operating model assuming continuous evidence collection, not a once-a-year sprint. Our SOC 2 audit guide walks through the steady-state operating model.

Frequently asked questions

Is ISO 27001 harder than SOC 2?

Not inherently, but the prescription is different. ISO 27001 forces you to address all 93 Annex A controls (or document exclusion with justification) and to demonstrate an operating ISMS with management review cycles. SOC 2 lets you pick the control population that maps to the criteria. ISO is “broader and more prescriptive”; SOC 2 is “narrower and more flexible.” First-time ISO 27001 implementations frequently take longer than first-time SOC 2 implementations because the ISMS clauses (management review, internal audit, continual improvement) require building organizational muscle that doesn’t exist in most early-stage companies.

Can the same auditor do both?

The audit firm can run both programs but the actual auditor often cannot. SOC 2 must be performed by a licensed CPA firm under SSAE 18. ISO 27001 must be performed by an ISO accredited certification body. Large firms (Schellman, A-LIGN, BDO, KPMG, Coalfire) operate both lines and coordinate them; smaller firms typically focus on one. Coordinating across two firms is operationally manageable but adds project-management overhead.

Do I need both for SOC 2 customers asking about ISO 27001?

Not necessarily. Many US procurement frameworks accept SOC 2 in lieu of ISO 27001 and vice versa. The exception is when the customer’s procurement framework explicitly requires both, which is becoming more common at F500 buyers post-2024 supply-chain regulation. Check the vendor questionnaire language; if it says “SOC 2 OR ISO 27001,” one is fine. If it says “SOC 2 AND ISO 27001,” you need both.

How long does each program take to implement from scratch?

SOC 2 Type 2 first time: 6 to 9 months including a 3 to 6 month observation period. ISO 27001 first time: 8 to 12 months including ISMS implementation and the Stage 1 + Stage 2 audit. The biggest gating factor for both is the maturity of the existing control environment; companies with mature controls can compress both timelines materially.

Does ISO 27001 cover privacy?

Partially. ISO 27001:2022 Annex A includes some privacy-adjacent controls. The dedicated privacy companion standard is ISO/IEC 27701 (Privacy Information Management System), which is added on top of ISO 27001. The SOC 2 privacy category and ISO 27701 cover similar ground and are roughly substitutable for GDPR procurement.

What does “accredited” mean for ISO certification bodies?

Accreditation is conferred by national accreditation bodies (UKAS in the UK, ANAB in the US, DAkkS in Germany). A certificate issued by a non-accredited body has limited procurement value. When evaluating ISO 27001 auditors, confirm which national accreditation body has accredited them; procurement teams read this on the certificate.

Can I lose ISO 27001 certification mid-cycle?

Yes. Surveillance audits in years 1 and 2 of the cycle can identify major non-conformities that suspend or withdraw the certification. The certification body has discretion. Common triggers include unaddressed major findings from the prior audit, security incidents that revealed control failures, and changes in scope (acquisitions, new product lines) that materially change the ISMS without proper update.

Which one helps more with cyber insurance underwriting?

Both help; the marginal effect is similar. Cyber insurance underwriters in 2026 increasingly treat SOC 2 Type 2 and ISO 27001 as effectively equivalent for the security maturity signal. The bigger underwriting drivers are MFA coverage, endpoint detection deployment, and backup architecture, none of which either program tests directly. See our learn library for further coverage.