Preparing for a PCI DSS audit can seem like a complex challenge, especially for companies facing it for the first time. The PCI DSS standard was created by five major payment organizations (Visa, Mastercard, JCB, Diners, and American Express) to ensure the security of cardholder data and mitigate online fraud. It consists of 12 core requirements and introduces very specific terminology and concepts. However, with proper planning and strategy, this process can be executed efficiently while minimizing the risk of errors and non-compliance. Below is a detailed guide outlining ten steps to help you prepare your organization for a PCI DSS audit.
1. Understanding Your Status in Payment Organizations
The first step in preparing for PCI DSS certification is determining whether your organization operates as a merchant, a service provider, or both. Merchants accept card payments and are classified based on transaction volume (Level 1-4), which impacts compliance requirements. Service providers offer services related to cardholder data and are usually subject to stricter requirements (Level 1 or 2). Incorrectly identifying your status can lead to certification errors and legal consequences, so it is crucial to thoroughly analyze how your company interacts with cardholder data.
2. Understanding Business Processes That Handle Cardholder Data
To effectively prepare for PCI DSS certification, you must thoroughly analyze your business processes related to cardholder data. If you are a merchant, define all payment channels (eCommerce, retail, call center, MOTO, P2PE, etc.) and how cardholder data is processed. Consider not just transactions but also refunds, chargebacks, pre-authorizations, 3DS, DCC, Account Updater, or BIN lookup. Check if and how you store cardholder data, the purpose of storing it, and the retention period. If you operate as a service provider, analyze the flow of cardholder data, processing channels, and whether all business processes are covered under PCI DSS certification (e.g., fraud detection, risk assessment, refunds, 3DS). It is also essential to define the locations included in the certification scope and verify whether your services are provided to merchants or other service providers. Understanding these aspects in detail allows for precise scope determination and helps avoid surprises during certification.
3. Defining the Scope of Certification (Scope Identification)
To effectively prepare for PCI DSS certification, you must clearly define which systems, applications, processes, and assets fall within its scope. A key factor is analyzing the flow of cardholder data—from its entry into your systems to its storage or transmission to a payment processor. If you are a service provider without direct access to cardholder data, you must demonstrate how your services impact its security. Starting from April 1, 2025, it will be mandatory to document the certification scope and conduct quarterly reviews. One way to reduce scope is through segmentation, which involves isolating systems that process cardholder data from the rest of the IT infrastructure (e.g., using Category 3 devices). Proper segmentation reduces the audit scope, simplifies preparations, and lowers costs, especially in cloud and containerized environments where micro-segmentation is used. If you have doubts, consulting with a PCI QSA auditor is recommended—after all, a 15-minute consultation is free.
4. Preparing Documentation for the Audit
The PCI DSS standard requires that your organization maintains complete and up-to-date documentation describing how it operates and meets compliance requirements. An audit is a comparison between documentation and the actual state of security, making the quality of documentation crucial. It must be comprehensive—each PCI DSS requirement should be addressed, even if it is covered under another document. It must also be current—no older than 12 months, regardless of whether you store it in SharePoint, Google Docs, Confluence, or a Wiki. Finally, it must be clear, providing well-structured descriptions of processes and procedures, including transparent diagrams (more on this topic can be found here). Proper documentation forms the foundation of a successful audit.
5. Training Your Team
People are the weakest link in the security chain, which is why regular team training is not only a PCI DSS requirement but also a critical component of effective data protection. Even the best technical safeguards will not suffice if employees are unaware of threats and do not know how to respond to them. Training should include security awareness (recognizing phishing attacks, secure cardholder data processing, cyber hygiene), secure coding (for developers), and incident response (for security monitoring teams). According to PCI DSS, training must be conducted at least once a year and during onboarding for new employees. Regular education increases awareness of threats and enables teams to respond more effectively to security incidents.
6. Verifying Your Vendors
In most cases, the Cardholder Data Environment (CDE) does not operate in isolation—it depends on external vendors. Identifying and verifying their PCI DSS compliance is critical. You must first determine what cardholder data is shared with the vendor—such as card numbers, CVV codes, expiration dates—and the extent of their access. Next, verify whether the vendor holds PCI DSS certification. If so, request an up-to-date Attestation of Compliance (AOC), which must not be older than 12 months. Service providers are required to provide AOCs to their clients (Requirement 12.9). Carefully review the received AOC—ensure it covers the services provided to your organization, is properly signed, and is current. Regular vendor assessments minimize the risk of security breaches resulting from third-party non-compliance with PCI DSS.
7. Reviewing Implemented Technical Controls
Security is constantly evolving, which means you must regularly review your implemented technical controls and adapt them to changing standards and threats. This includes updating encryption algorithms, key lengths, secure system configurations, and coding practices. Your IT infrastructure should be protected against attacks through encryption, regular software and system updates, and secure configurations. Penetration testing and vulnerability scans are critical as they help assess security effectiveness and identify areas that require improvement. PCI DSS mandates quarterly scanning, penetration testing at least once per year and after significant changes, and segmentation testing every six months for service providers. Ongoing verification of technical controls is fundamental to maintaining robust security defenses against cyber threats.
8. Conducting an Internal Audit
Before proceeding with a formal PCI DSS audit, conducting an internal compliance audit—or, for first-time organizations, a gap analysis—is recommended. This helps detect and address deficiencies early, test documentation and systems, and prepare your team for the formal assessment. An internal audit can be performed by the IT team or an external expert, but the key factor is ensuring the person conducting it has experience and can provide precise answers. This step ensures your organization meets PCI DSS requirements and is ready for external assessment while minimizing non-compliance risks.
9. Gathering Audit Evidence and Preparing the Team
The PCI DSS audit consists of multiple phases (more on this topic can be found here), so proper preparation is crucial. First, refresh your knowledge of documentation, prepare sample tickets and reports proving compliance with PCI DSS processes, and ensure a thorough understanding of card processing—where it occurs and who is responsible. Providing access to necessary tools and logs is essential to ensuring the audit runs smoothly. Lack of preparation—such as an administrator unable to demonstrate time server configuration or a developer without access to test results—can undermine the auditor’s trust. Remember that audits primarily involve interviews and observations—your team must be ready to present compliance evidence efficiently.
10. Collaborating with a QSA During the Audit
The final step in the PCI DSS certification process is working with a certified PCI QSA (Qualified Security Assessor) during the formal audit. The QSA is a specialist who will conduct a thorough evaluation of your company’s implemented solutions and assess whether they meet all PCI DSS requirements.
Although audits may cause some concern, there is no need to stress—the key is to approach the process with well-prepared documentation and compliance evidence. The audit not only assesses the current state but also serves as an opportunity to gain valuable insights and recommendations from an expert. It is a chance to improve your company’s security processes and prevent potential issues in the future.
Keep in mind that the role of the QSA is not just to assess compliance but also to assist in the verification process. Use the audit as an opportunity to strengthen your security measures and align with best practices for data protection.
Preparing for a PCI DSS audit requires dedication and attention to detail, but it can be successfully achieved with the right approach. Proper planning, gap analysis, security implementations, team training, and collaboration with a QSA are essential factors in achieving compliance.
At Patronusec, we provide comprehensive support at every stage of this process—contact us to ensure the security and success of your company.
