Many businesses use the terms SSAE 18 and SOC 2 interchangeably, but they refer to different aspects of the audit process. SSAE 18 is the auditing standard used by licensed CPA firms, while SOC 2 is the reporting framework that evaluates an organization’s security controls. This guide explains the differences, how they work together, and which one your business needs to demonstrate strong security and compliance.
As organizations increasingly rely on cloud computing and digital services, customers expect assurance that their sensitive data is handled securely. This has made compliance frameworks like SOC 2 an important part of doing business, especially for SaaS companies, cloud service providers, managed service providers (MSPs), FinTech companies, and healthcare technology organizations.
During the compliance journey, many organizations come across another term: SSAE 18. Because both terms often appear together, it’s common to assume they mean the same thing. In reality, they serve different purposes.
Understanding the difference between SSAE 18 and SOC 2 is essential for choosing the right compliance strategy and communicating confidently with customers, auditors, and stakeholders.
What Is SSAE 18?
SSAE 18 (Statement on Standards for Attestation Engagements No. 18) is an auditing standard issued by the American Institute of Certified Public Accountants (AICPA).
It provides the professional guidelines that licensed CPA firms follow when performing attestation engagements, including SOC examinations.
Rather than being a compliance certification, SSAE 18 establishes how auditors should:
- Plan an engagement
- Evaluate evidence
- Assess internal controls
- Review third-party service providers
- Issue independent reports
In simple terms, SSAE 18 tells auditors how to perform the audit.
What Is SOC 2?
SOC 2 is a reporting framework developed by the AICPA to evaluate how organizations protect customer data.
Unlike SSAE 18, SOC 2 focuses on what is being evaluated rather than how the audit is performed.
SOC 2 examines an organization’s controls against the Trust Services Criteria, which include:
- Security (mandatory)
- Availability
- Processing Integrity
- Confidentiality
- Privacy
Organizations receive a SOC 2 report after an independent CPA firm evaluates their security controls.
The Biggest Difference
The easiest way to understand the relationship is:
- SSAE 18 is the auditing standard.
- SOC 2 is the compliance reporting framework.
A CPA firm performs a SOC 2 audit by following the requirements defined in SSAE 18.
Think of it like building a house:
- SSAE 18 is the construction process.
- SOC 2 is the completed inspection report showing the house meets required standards.
SSAE 18 vs SOC 2 Comparison
| Feature | SSAE 18 | SOC 2 |
|---|---|---|
| Purpose | Auditing standard | Compliance reporting framework |
| Developed By | AICPA | AICPA |
| Used By | Licensed CPA firms | Organizations handling customer data |
| Focus | How the audit is performed | Security controls being evaluated |
| Report Issued | No | Yes |
| Security Evaluation | No | Yes |
| Customer Assurance | Indirect | Direct |
How SSAE 18 and SOC 2 Work Together
SSAE 18 and SOC 2 are complementary.
During a SOC 2 engagement:
- A CPA firm follows SSAE 18 auditing standards.
- The organization is evaluated against the SOC 2 Trust Services Criteria.
- Evidence is reviewed.
- Security controls are tested.
- A SOC 2 report is issued.
Without SSAE 18, auditors would not have a consistent methodology for performing SOC 2 examinations.
SOC 2 Type I and Type II
SOC 2 reports are available in two formats.
SOC 2 Type I
Evaluates whether security controls are properly designed at a specific point in time.
Ideal for organizations beginning their compliance journey.
SOC 2 Type II
Evaluates whether controls operated effectively over an observation period, typically between three and twelve months.
Enterprise customers usually prefer a Type II report because it demonstrates ongoing operational effectiveness.
Why Businesses Choose SOC 2
Organizations pursue SOC 2 because it helps them:
- Build customer trust
- Win enterprise contracts
- Strengthen cybersecurity
- Meet vendor security requirements
- Demonstrate operational maturity
- Improve internal governance
- Support regulatory obligations
SOC 2 has become a widely recognized benchmark for information security across many industries.
Why SSAE 18 Matters
Although customers rarely ask whether an audit followed SSAE 18, they rely on it indirectly.
Because every SOC 2 examination is conducted according to SSAE 18 standards, customers can trust that:
- The audit followed recognized professional practices.
- Evidence was evaluated independently.
- Security controls were reviewed consistently.
- The report is reliable and objective.
This consistency is one of the reasons SOC reports are trusted worldwide.
Common Misconceptions
“SSAE 18 is a certification.”
Incorrect.
SSAE 18 is an auditing standard, not a certification or compliance framework.
“SOC 2 replaces SSAE 18.”
No.
SOC 2 reports are performed under SSAE 18 auditing standards.
“Businesses become SSAE 18 compliant.”
Not exactly.
Organizations receive a SOC report from an audit conducted in accordance with SSAE 18. The compliance focus is generally on the SOC report, not on becoming “SSAE 18 compliant.”
“Only large enterprises need SOC 2.”
Many startups and growing SaaS companies pursue SOC 2 because enterprise customers often require it during procurement.
Which One Does Your Organization Need?
If your goal is to demonstrate strong security controls and satisfy customer requirements, you should pursue a SOC 2 audit.
Your chosen CPA firm will automatically conduct that audit using SSAE 18 standards.
In other words, organizations don’t choose between SSAE 18 and SOC 2. They pursue a SOC 2 report, while the auditor follows SSAE 18 during the examination.
Conclusion
Although SSAE 18 and SOC 2 are closely connected, they serve different purposes. SSAE 18 is the professional auditing standard that guides how licensed CPA firms perform attestation engagements, while SOC 2 is the framework used to evaluate an organization’s security controls based on the Trust Services Criteria.
Understanding this distinction helps organizations make informed compliance decisions and communicate more effectively with customers and stakeholders. If your business stores or processes customer data, investing in SOC 2 not only demonstrates a commitment to security but also strengthens customer confidence, supports enterprise sales, and builds a foundation for long-term compliance.
Frequently Asked Questions
Is SSAE 18 the same as SOC 2?
No. SSAE 18 is the auditing standard used by CPA firms, while SOC 2 is the reporting framework used to evaluate an organization’s security controls.
Can a company be SSAE 18 certified?
No. SSAE 18 is not a certification. Organizations receive a SOC report after an audit conducted in accordance with SSAE 18 standards.
Does SOC 2 require SSAE 18?
Yes. SOC 2 audits are performed by licensed CPA firms following SSAE 18 auditing standards.
Which is more important for customers?
Most customers request a SOC 2 report because it provides independent assurance that your organization has implemented effective security controls.
Who should pursue SOC 2?
SOC 2 is recommended for SaaS companies, cloud service providers, MSPs, FinTech organizations, healthcare technology providers, and businesses that handle sensitive customer information.
