Schellman vs A-LIGN vs Coalfire

Choosing among Schellman, A-LIGN, and Coalfire for a SOC 2 audit usually comes down to which flavor of large-scale, multi-framework audit firm fits your compliance program. All three are established CPA firms serving mid-market and enterprise clients well beyond a single SOC 2 engagement, but they differ in industry focus, audit volume, and how much federal or advisory work sits alongside the SOC 2 practice. Buyers researching Schellman vs A-LIGN vs Coalfire are typically choosing among three well-known national firms rather than deciding between a boutique and a generalist. For a wider shortlist beyond these three firms, see the SOC 2 Auditors Directory.

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Quick Comparison of Schellman, A-LIGN, and Coalfire

The industries served, company size focus, platforms supported, and headquarters values above come directly from each firm's SOC2Auditors.io directory record, verified separately from the sourced claims below, not from an editorial assessment.

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Schellman

Schellman began as a SOC audit firm more than 20 years ago and says it still issues more than 2,000 SOC reports a year, having since expanded to nearly 60 types of audits and assessments overall, according to Schellman's own site. Schellman's SOC 2 service page describes a four-phase examination process, planning and preparation, evidence request and collection, testing, and reporting, and notes that a Type 2 examination period typically covers six months or more (schellman.com/services/soc-compliance-and-attestations/soc-2). The same page states Schellman is an accredited FedRAMP Third-Party Assessment Organization and one of the first organizations cleared as a CMMC Third-Party Assessment Organization, supporting its directory focus on government clients alongside SaaS and technology (schellman.com/services/soc-compliance-and-attestations/soc-2).

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A-LIGN

A-LIGN was founded in 2009 and describes itself as a technology-enabled security and compliance partner trusted by more than 5,000 global organizations, according to A-LIGN's own about page. A-LIGN's SOC 2 service page states it has completed more than 13,800 SOC 2 audits with a 96% client satisfaction rating and positions itself as the world's number one issuer of SOC 2 reports (a-lign.com/service/soc-2). The same page describes A-LIGN's own audit management platform, A-SCEND, which the firm says maps shared requirements across SOC 2, SOC 1, ISO 27001, and HIPAA so a client's evidence can be reused across frameworks instead of resubmitted for each one (a-lign.com/service/soc-2).

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Coalfire

Coalfire describes itself on its company story page as securing the cloud for more than 700 cloud service partners and says it was first to assess compliance with key frameworks including CMMC and PCI, alongside more than 20 years in cybersecurity (coalfire.com/about). The same page states Coalfire pioneered an Accelerated Cloud Engineering methodology with AWS that the firm says cut client time to market by 80% (coalfire.com/about). Coalfire's SOC assessment services page states its SOC reports are issued through Coalfire Controls, an affiliate that is a fully licensed, accredited CPA firm (coalfire.com/soc-assessment-services).

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What Is a Large-Scale SOC 2 Audit Firm

A large-scale SOC 2 audit firm is a licensed CPA firm that runs SOC 2 examinations at high enough volume, and across enough adjacent frameworks, that a client can move from a first Type I report into a multi-framework enterprise compliance program without switching auditors. Schellman, A-LIGN, and Coalfire all fit this description: each issues thousands of SOC reports a year, each holds accreditations well beyond SOC 2 alone such as FedRAMP, CMMC, ISO 27001, or HITRUST, and each has built or licensed its own audit management technology rather than relying only on a client's compliance automation platform for evidence collection. The tradeoff against a smaller, boutique firm is rarely about audit quality; it is about engagement style. A larger firm's scoping process is more standardized, its internal review layers are heavier, and its pricing is less likely to flex for an unusually small or early-stage client. None of the three firms below is the objectively better choice; the right fit depends on which firm's industry focus, company size focus, and platform experience match the company being audited.

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Schellman vs A-LIGN vs Coalfire FAQs

Is Schellman, A-LIGN, or Coalfire the better SOC 2 auditor?

Neither is objectively better. Schellman and A-LIGN both run high volumes of SOC 2 examinations from a similar mid-market to enterprise client base, while Coalfire's advisory arm leans further into federal and cloud-security work alongside SOC 2.

Does A-LIGN's SOC 2 volume make it faster than Schellman or Coalfire?

Not necessarily. A-LIGN's directory record lists a 6 to 8 week timeline, close to Schellman's 6 to 10 weeks, while Coalfire's listed 6 to 9 month timeline reflects a combined advisory-plus-audit engagement rather than audit fieldwork alone.

Do all three firms issue the SOC 2 report through their own CPA license?

Yes. Schellman and A-LIGN are both licensed CPA firms in their own right, and Coalfire issues its SOC reports through Coalfire Controls, its fully licensed CPA affiliate.

Which platforms does each firm already work with?

Schellman's directory record lists Drata and Vanta, A-LIGN's lists Drata, Hyperproof, Secureframe, and Vanta, and Coalfire's lists Drata and Vanta.

Can all three firms handle a FedRAMP or CMMC engagement alongside SOC 2?

Not equally. Schellman states it is an accredited FedRAMP 3PAO and one of the first CMMC C3PAOs, and Coalfire's advisory business centers on FedRAMP and CMMC work, but A-LIGN's directory record does not list Government among its served industries, so a federal engagement is a stronger fit for the other two.

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Choosing Between Schellman, A-LIGN, and Coalfire

The comparison above is a starting point, not a final answer. The SOC 2 Auditors Directory lets you filter by industry, company size, and platform experience to build a fuller shortlist beyond these three firms, and our guide on how to choose a SOC 2 auditor covers the questions worth asking before you sign an engagement letter.

Sources

• Schellman's own site states the firm began as a SOC audit firm more than 20 years ago and still issues more than 2,000 SOC reports a year: https://www.schellman.com
• Schellman's SOC 2 service page describes a four-phase examination process and notes a Type 2 examination period typically covers six months or more: https://www.schellman.com/services/soc-compliance-and-attestations/soc-2
• Schellman's SOC 2 service page states the firm is an accredited FedRAMP 3PAO and one of the first CMMC C3PAOs: https://www.schellman.com/services/soc-compliance-and-attestations/soc-2
• A-LIGN's about page states the firm was founded in 2009 and is trusted by more than 5,000 global organizations: https://www.a-lign.com/about
• A-LIGN's SOC 2 service page states it has completed more than 13,800 SOC 2 audits with a 96% client satisfaction rating: https://www.a-lign.com/service/soc-2
• A-LIGN's SOC 2 service page describes its A-SCEND platform mapping shared requirements across SOC 2, SOC 1, ISO 27001, and HIPAA: https://www.a-lign.com/service/soc-2
• Coalfire's company story page states it secures more than 700 cloud service partners and was first to assess compliance with key frameworks including CMMC and PCI: https://coalfire.com/about
• Coalfire's company story page states it pioneered an Accelerated Cloud Engineering methodology with AWS: https://coalfire.com/about
• Coalfire's SOC assessment services page states its SOC reports are issued through Coalfire Controls, a fully licensed, accredited CPA affiliate: https://coalfire.com/soc-assessment-services