Locked Stack is an independent cybersecurity consultancy and managed services firm with headquarters in London, United Kingdom, and Dover, Delaware, operating across North America, Europe, and the UK.

We specialise in payment security and broader risk management, delivering structured advisory and managed services that support regulatory and industry standards across both business and technology environments. Our capabilities span PCI DSS, PCI 3DS, ISO/IEC 27001/2, GDPR, DORA, GLBA, HIPAA, and the UK Data Protection Act.

Payment card security is central to Locked Stack’s offering. Our team has practical, end-to-end experience across the payments landscape, working with issuers, acquirers, card networks, and third-party service providers.

We work with organisations ranging from growing enterprises to public sector bodies, providing repeatable and sustainable compliance programs designed to deliver measurable value over time. Our technology-assisted approach reduces assessment effort, shortens compliance timelines, and supports ongoing regulatory alignment.

Our consultants bring extensive real-world experience in security assurance, risk, and regulatory delivery, with prior roles in global enterprise environments. This depth of experience allows us to address complex security and compliance challenges with confidence and scale.

  • Helping you strengthen operational resilience under the Digital Operational Resilience Act (DORA). We provide assessor-informed guidance and gap analysis services, supporting organisations in meeting DORA’s ICT risk, incident reporting, resilience testing, third-party risk, and information-sharing requirements across EU and global operations. Read More

  • PCI DSS 4.0.1 and payment security advisory services tailored to support secure processing, strong authentication, and compliance readiness. We provide PCI DSS assessments, gap analyses, pre-audit reviews, 3-D Secure evaluations, and SAQ guidance to help organisations strengthen payment security and meet evolving standards. Read More

  • Using the NIST Cybersecurity Framework 2.0, we assess organisational resilience through a structured review of governance, controls, and maturity across Identify, Protect, Detect, Respond, and Recover functions. Our approach delivers clear insights, highlights gaps, and supports strengthened operational resilience. Read More

  • Comprehensive penetration testing and security assessment services designed to strengthen resilience and support compliance. We deliver application, external, internal, and segmentation testing through trusted partners, using risk-based methodologies to identify vulnerabilities, enhance defences, and maintain alignment with PCI DSS, ISO 27001, NIST, and industry standards. Read More

  • GDPR compliance and data governance consulting that strengthens accountability, transparency, and responsible data management. We support organisations with policy development, data subject rights, consent, retention, breach readiness, and lawful processing, delivering pragmatic guidance aligned to EU and UK requirements. Led by our data protection specialist. Read More

  • ISO 27001 readiness and information security consulting that strengthens governance, resilience, and certification preparedness. We assess existing controls, identify gaps, and guide the development of robust ISMS practices aligned with confidentiality, integrity, and availability principles—supporting long-term security maturity and global compliance. Read More

  • Vulnerability scanning and continuous security monitoring that support proactive risk management and PCI DSS compliance. We deliver internal and external scanning, continuous visibility, and real-time insight into emerging threats—helping organisations identify weaknesses early, prioritise remediation, and strengthen overall security posture. Read More

  • Security awareness and cyber training solutions that strengthen the human layer of defence. We provide tailored eLearning, phishing simulations, and ongoing programme management to build organisational vigilance, reduce human error, and support a strong security culture backed by clear executive reporting. Read More

Contact us

Get in touch with our team to discuss your cybersecurity and governance needs, or to learn how our services can strengthen your organisation’s security posture. Whether you require support with compliance, infrastructure, or risk management, we’re here to help.

Address

71 - 75 Shelton Street

Covent garden

London

United Kingsdom

WC2H 9JQ

☎ +44 20 7072 8803