PCI DSS compliance testing: What fintech companies need to know before their assessment
Fintech companies handle millions of card transactions every day, making them a prime target for cybercriminals and a high priority for regulators. As cyberattacks become more sophisticated and customers grow increasingly aware of how valuable their data is, PCI DSS compliance has become a make-or-break factor for fintechs. It separates the platforms customers trust from those hit with fines, legal trouble, and an exodus of users.
The smartest fintechs are now using compliance testing to give them a competitive edge, helping them build credibility, win customer trust, and tighten their security posture.
What is PCI DSS compliance?
The Payment Card Industry Data Security Standard (PCI DSS) is a global framework designed to protect cardholder data wherever it’s stored, processed, or transmitted. Developed by the major card brands (including Visa, Mastercard, and American Express), it’s managed by the PCI Security Standards Council, which updates requirements regularly to stay ahead of new cyber threats.
For fintech companies, PCI DSS compliance can be particularly complex. Unlike a traditional retailer, where transactions happen at a single terminal, fintechs operate in complex, digital-first ecosystems. Cardholder data flows through multiple systems, APIs link to payment processors and banking partners, and third-party integrations create more potential entry points for attackers.
Add in rapid scaling, where a simple payment flow can quickly turn into a sprawling network of services, and the compliance challenge only grows.
The standard applies to any organisation that accepts, processes, stores, or transmits credit card information. For fintechs with high transaction volumes or sensitive authentication data, the bar is higher, with stricter requirements, more paperwork, and frequent independent assessments.
What are the PCI DSS requirements for fintech companies?
When PCI DSS launched in 2006, it unified different card brand security programs into a single standard. Today, its 12 requirements fall into six broad categories:
- Secure networks: firewalls and strong, unique system passwords
- Data protection: encrypt cardholder data at rest and in transit
- Vulnerability management: regular testing and up-to-date antivirus software
- Access controls: restrict data access to business needs, use unique IDs, and limit physical access
- Regular monitoring: track network activity and test security systems frequently
- Information security policies: keep documentation current and enforce it
What challenges and consequences do fintech companies face?
Fintech companies face specific challenges within these requirements:
- Mobile apps must secure data across devices, platforms, and OS versions
- Cloud hosting often means shared responsibility for security across multiple vendors
- Cross-border payments add extra layers of regulation around data residency and transfers
Non-compliance is costly. Fines can reach $5,000 to $10,000 per month, and breaches lead to chargebacks, forensic investigations, and the worst blow of all: losing customer trust overnight.
PCI DSS compliance testing: Scope, process, and expectations
PCI DSS compliance testing goes beyond basic security audits. It’s a structured, hands-on evaluation to confirm your systems can actually stand up to real-world attack scenarios, not just that they exist on paper.
Testing types include:
- Internal vulnerability scans: run from within your network to find weaknesses insiders could exploit
- External vulnerability scans: performed by Approved Scanning Vendors (ASVs) to spot internet-facing risks
- Annual Fintech penetration tests: simulate cyberattacks to test your defences at both the network and application level
For fintech companies, testing must go further:
- Validate authentication flows for all user types
- Probe API endpoints for injection attacks, authorisation flaws, and rate limiting issues
- Check data segmentation to ensure cardholder data stays isolated
- Confirm encryption works at every stage: at rest, in transit, and in processing
How often you test can depend on system changes. New payment integrations, major software updates, or infrastructure modifications might trigger additional testing cycles.
Many successful fintechs also don’t wait for a quarterly deadline: they run 24/7 automated internal scans to catch issues early and avoid last-minute surprises.
PCI DSS penetration testing: Best practices for passing your assessment
The PCI Security Standards Council recommends testing that mimics actual attacker behaviour, targeting both network and application vulnerabilities.
Choose qualified testers
Selecting qualified testers can make or break your assessment. Look for certifications (CISSP, CEH, OSCP) and proven fintech payment system experience. Ask about API gateway testing, tokenisation, and multi-tenant architecture assessments.
Perform segmentation testing
Segmentation can dramatically reduce PCI scope, but only if it works. Testers should try pivoting between network segments to see if they can reach cardholder data from out-of-scope systems.
Set clear testing boundaries
Avoid testing during peak traffic. Set testing windows, escalation contacts, and agreed testing methods before starting.
Retest after fixes
Don’t wait until the next formal assessment. Retest critical fixes right away to confirm they’re working and not creating new vulnerabilities.
How can fintechs prepare for PCI DSS compliance testing?
1. Define scope and map assets
List every system that stores, processes, or transmits cardholder data. Map data flows from entry to exit and include all connected systems. One overlooked database can invalidate an entire assessment.
2. Identify PCI level and integration model
Your transaction volume determines your PCI level, from Level 1 (over 6 million transactions annually) to Level 4 (under 20,000). Integration choices matter too: using tokenisation providers like Stripe can dramatically reduce compliance scope.
3. Self-assess and collect evidence
Complete the right Self-Assessment Questionnaire (SAQ). Gather diagrams, policies, scan reports, and access records.
4. Pick the right vendors
Choose ASVs from the PCI Council’s list. For Level 1, hire a Qualified Security Assessor (QSA) with fintech experience and strong references.
5. Remediate and retest
Fix vulnerabilities early, schedule retests, and build buffer time into your compliance plan.
Common PCI DSS compliance pitfalls (and how fintechs can avoid them)
When it comes to PCI DSS compliance, common pitfalls include:
- Incorrect scoping that misses critical systems or underestimates data flows
- Third-party integration risks that introduce unexpected vulnerabilities
- Incomplete documentation that frustrates assessors and delays certification
- Weak change control processes that allow new vulnerabilities between assessments
Fintech companies can avoid these by:
- Using continuous vulnerability scanning rather than quarterly snapshots
- Practising proper vendor management with security questionnaires and regular access reviews
- Organising regular staff training to ensure teams understand their compliance role
- Using automated data discovery tools to identify where cardholder data actually lives.
Ready to streamline your PCI DSS compliance with OnSecurity’s fintech-focused penetration testing? Get an instant quote today and ensure your payment systems meet the highest security standards.
