ISAE 3402: the assurance report that validates the security and effectiveness of our HR outsourcing

ISAE 3402 is the international standard that certifies, through an independent audit, that the internal controls of an outsourced service provider are properly designed and operate effectively over time (Type I and Type II reports). At Adlanter, we have maintained it since 2017 to ensure security, traceability, and compliance in critical HR and payroll processes.

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What is ISAE 3402 and why does it matter for outsourced payroll and HR?

ISAE 3402 (International Standard on Assurance Engagements 3402) allows an independent auditor to assess and certify the internal controls of a provider that delivers outsourced services, providing evidence to clients and their auditors regarding the reliability and transparency of the delegated processes (payroll, employee data, access, communications with authorities, etc.).

Unlike generic certifications, the ISAE 3402 report is issued specifically over the services we deliver to each client, reviewing the design of the controls, their operating effectiveness, and the alignment with frameworks and regulations such as ISO/IEC 27001 or data protection, where applicable to the service.

Type I vs. Type II: what the auditor actually looks at

• Type I: an opinion on whether the controls are suitably designed and in operation at a specific point in time.
• Type II: in addition to design, it concludes whether the controls have been effective over a defined period.

For your company, this means demonstrating not only that a control framework exists, but that it works properly day to day.

 What does our ISAE 3402 audit cover?

In the context of HR/payroll outsourcing, the audit reviews, among other things, these critical controls: security of physical and logical access, change management in payroll systems, payroll calculation, payment and communication, data exchange with clients and authorities, backups and contingency, aligned with frameworks such as ISO/IEC 27001 and GDPR where applicable to the service.

How is ISAE 3402 obtained and maintained?

The assurance process is carried out in two phases:

• Design: analysis and validation of the procedures manual and the controls applied in each process.
• Effectiveness: verification that the controls are properly applied and effective throughout the audited period.

Why is it important for our clients?

Having ISAE 3402 certification brings key advantages in labor advisory services:

• Security and trust: peace of mind knowing that an independent auditor validates our HR processes.
• Regulatory compliance: assurance of alignment with international standards and current legislation.
• Efficiency in internal and external audits: the ISAE 3402 report is a solid basis for our clients’ auditors to confirm the quality and security of outsourced processes.
• Competitive advantage: many organizations, especially international ones, require this certification as a prerequisite to work with a provider.

Direct benefits for your company

• Less friction in internal and external audits: Your auditors can rely on our ISAE 3402/SOC 1 report to assess controls of the outsourced service that affect your financial statements, reducing duplicate testing and time.
• Verifiable confidence with independent evidence: A qualified third party evaluates our controls; if it is Type II, it also validates that they have operated effectively throughout the entire audited period, providing a higher level of assurance.
• Meeting procurement requirements (especially in international groups): Many organizations require SOC 1/ISAE 3402 from providers of critical processes such as payroll and HR, which facilitates vendor approval and shortens due diligence.
• Reduced operational risk in HR and payroll: Areas such as access, change management, calculation/payment, and continuity are under designed and tested controls, which raises the reliability of the service.

Our track record: certified since 2017

At Adlanter, we have maintained ISAE 3402 continuously since 2017, which positions us as a reliable, secure, and audited provider of labor and outsourcing services.

ISAE 3402 vs ISO 27001: how do they differ and why do we care about both?

• ISO 27001: certifies that we have an Information Security Management System (ISMS) that manages risks to confidentiality, integrity, and availability. It is a certification with a defined scope.
• ISAE 3402: does not certify; it reports (third‑party audit) on controls of outsourced services that impact clients’ financial information.

Both approaches are complementary: ISO 27001 strengthens transversal security; ISAE 3402 provides specific evidence for your auditors regarding outsourced processes relevant to financial reporting.

How does ISAE 3402 apply to our labor advisory service?

Our labor advisory service is designed to offer:

• End‑to‑end payroll and employment contract management.
• Advice on labor regulations and collective bargaining agreements.
• Processing registrations, terminations, and changes.
• Representation before public authorities.
• Document control and data protection.

All of this is underpinned by processes certified under ISAE 3402, ensuring traceability, security, and compliance.

At Adlanter, we believe that excellence is non‑negotiable. That’s why our labor advisory with ISAE 3402 is much more than a service: it is a guarantee of security, compliance, and reliability.
Would you like to work with a certified provider that protects your HR processes? Contact us with no obligation.