Choosing a data protection audit provider is not simply about checking whether the right policies exist. A thorough audit can reveal how personal data is actually collected, stored, shared and protected across day-to-day operations.
The UK has a broad mix of data protection audit providers, from major professional services firms to specialist privacy and cybersecurity consultancies. Their work can cover UK GDPR compliance, data mapping, governance controls, processing activities, third-party risks and the practical handling of personal information.
This guide presents a selection of companies providing data protection audit services in the UK. It is not a ranking. Instead, it offers practical context on who the providers are, the organisations they work with and the main areas covered by their audit and advisory services.
Acumon
Acumon is a UK firm of chartered accountants and registered auditors providing data protection audit services to companies, charities, and international corporate groups.
The firm works with organisations ranging from growing owner-managed businesses and charities through to larger corporate groups and regulated entities. Data protection audits are delivered through a structured, risk-based review of how personal data is collected, processed, stored, shared, retained, and protected across the organisation.
Acumon holds a Public Interest Entity (PIE) audit licence and has experience working with listed companies and other entities subject to enhanced regulatory oversight in the United Kingdom. This background supports data protection audit work for organisations operating under strict governance, reporting, and control requirements.
In addition to its UK audit registration, Acumon holds audit licences in several international financial centres, including the Cayman Islands, British Virgin Islands (BVI), Jersey, and Isle of Man. These registrations support work with international corporate groups where personal data, operational systems, and reporting responsibilities extend across several jurisdictions.
International group structures frequently combine UK operating companies with offshore holding entities, particularly in sectors such as investment management, technology, energy, and international trade. Reviewing data protection arrangements across these structures requires an understanding of cross-border data flows, group-level responsibilities, third-party access, record keeping, and internal control frameworks.
Acumon works with finance teams, boards, compliance functions, and senior management to assess data protection controls while helping organisations improve governance arrangements, documentation, reporting processes, and internal accountability as they grow.
Data Protection Audit Capabilities:
Acumon provides data protection audit services across a wide range of organisational structures and sectors.
These include:
- UK limited companies and corporate groups
- Public Interest Entities (PIEs) and regulated organisations
- UK subsidiaries of international groups
- charities and not-for-profit organisations
- owner-managed businesses approaching statutory audit thresholds
- offshore holding companies and investment vehicles
Data protection audit engagements are led by senior professionals who remain directly involved throughout the review. The work focuses on how data protection responsibilities are assigned, documented, monitored, and supported by internal processes.
Regulatory Licences and Registrations:
Acumon holds several audit registrations that support its work with organisations operating across multiple jurisdictions.
These include:
- UK statutory audit registration
- Public Interest Entity (PIE) audit licence
- Jersey audit licence
- Isle of Man audit licence
- Cayman Islands audit licence
- British Virgin Islands audit licence
These registrations allow the firm to work with groups that include entities in both the UK and key international financial centres, including organisations with cross-border data processing arrangements and shared operational systems.
Core Services:
Alongside data protection audit services, Acumon provides a range of services supporting financial reporting, governance, risk management, and internal controls.
These include:
- statutory external audit
- group and subsidiary audits
- Public Interest Entity (PIE) audits
- charity and not-for-profit audit
- audit of international group structures
- internal audit and governance reviews
- risk management and compliance support
Data protection audit work is delivered alongside discussions with management and boards regarding accountability, documentation, control ownership, reporting lines, and the management of data protection risks.
Organisations review their data protection arrangements when they grow, introduce new systems, expand into new jurisdictions, work with additional service providers, or process larger volumes of personal data.
Acumon works with businesses that are:
- approaching their first statutory audit
- preparing for external investment
- expanding into international markets
- operating within corporate group structures
Early engagement supports the review of data inventories, policies, contracts, retention procedures, access controls, breach response processes, and governance records before weaknesses become embedded across the organisation.
Contact Information:
- Website: acumon.com
- Phone: 020 8567 3451
- E-mail: mail@acumon.com
- Address: 1-2 Craven Road, Ealing, London, W5 2UA, UK
Evalian
Evalian is a specialist consultancy working across data protection, information security, cyber security, penetration testing and ISO certification. They have offices in Southampton, London, Worcester, Manchester and Dublin, with consultants based across the UK. Their clients range from start-ups to multinational organisations, and they work both directly and through delivery partners.
Their approach starts with the organisation itself. Before making recommendations, they look at its structure, working practices, culture, management systems and objectives. Data protection audits are shaped around real processes and risks, rather than a fixed checklist, with clear findings and practical actions for the team to take forward.
Key Highlights:
- Specialist data protection and security consultancy
- Offices and consultants across the UK
- Risk-led working method
- ISO 9001, ISO 27001 and ISO 22301 certified
- Cyber Essentials Plus certified
- CREST approved for selected cyber security services
Services:
- GDPR and data protection audits
- GDPR gap analysis
- Data protection compliance
- Data protection policies and procedures
- Outsourced data protection officer services
- Information security consultancy
- ISO 27001 and ISO 27701 consultancy
- Penetration testing
- Vulnerability assessments
Contact Information:
- Website: evalian.co.uk
- Phone: 03330 500 111
- E-mail: hello@evalian.co.uk
- Address: Blackwell House, Guildhall Yard, London, EC2V 5AE
- LinkedIn: www.linkedin.com/company/evalian
BDO
BDO is an accountancy and business advisory firm working with entrepreneurial, growing and mid-market organisations. Their UK practice covers Audit, Tax, Deals, Consulting, Risk and Outsourcing, with teams operating across the UK and Ireland. They are also part of the wider BDO International network.
Their privacy and data protection work forms part of a broader advisory practice that includes governance, regulation and operational risk. They work with organisations reviewing how personal data is managed across teams, systems and internal processes, as well as businesses building more formal privacy controls as they grow.
Key Highlights:
- UK accountancy and business advisory firm
- Part of the BDO International network
- Focus on growing and mid-market organisations
- Privacy work linked with wider risk and governance services
- Offices across the UK and Ireland
Services:
- Privacy and data protection advisory
- GDPR compliance reviews
- Data protection risk assessments
- Governance reviews
- Internal control reviews
- Regulatory compliance consulting
- Risk advisory
- Audit and assurance
- Business advisory services
Contact Information:
- Website: www.bdo.co.uk
- Phone: 0161 817 7500
- Address: Eden Building, Irwell Street, Salford, Manchester, M3 5EN, United Kingdom
- LinkedIn: www.linkedin.com/company/bdo-llp
- Instagram: www.instagram.com/bdo_uk
KPMG
KPMG provides audit, tax, legal and advisory services through member firms of the KPMG global organisation. Their personal data protection work sits within Cyber Advisory and combines legal, organisational and technical expertise. They work with businesses reviewing how privacy requirements affect processes, systems and internal controls.
Their GDPR projects follow a structured process, starting with an assessment of current practices and the identification of gaps. From there, they review risks, recommend controls, prepare policies and documentation, and assist with implementation. They also provide training and knowledge testing for employees, managers and specialist teams.
Key Highlights:
- Multidisciplinary privacy and cyber advisory team
- Structured GDPR project methodology
- Work covers processes, systems and governance
- Services adapted to the client's industry and operating model
- Focus on ongoing privacy management
Services:
- GDPR consulting
- GDPR gap assessments
- Personal data protection audits
- Privacy risk assessments
- Process and control reviews
- Policy and procedure development
- Data processing registers
- Internal compliance documentation
- Technical requirements
- Staff training and workshops
- Knowledge assessments
- Implementation support
- Cyber security testing
Contact Information:
- Website: kpmg.com
- Phone: +44 (0)161 246 4000
- Address: 1, St Peter's Square, Manchester M2 3AE, United Kingdom
- Twitter: x.com/kpmguk
- Facebook: www.facebook.com/KPMG
- LinkedIn: www.linkedin.com/company/kpmg-uk
PwC
PwC UK is a professional services firm working across audit, consulting, deals, risk and tax. Their clients include private companies, public bodies, third-sector organisations and multinational groups. Data protection work sits within their wider technology, data and risk capabilities.
Their teams look at privacy across governance, operational processes, technology platforms and regulatory controls. This allows them to review how personal data is handled across different departments and systems, particularly within organisations managing complex data environments or wider technology change.
Key Highlights:
- UK professional services firm
- Data protection work within technology and data risk consulting
- Works with private, public and third-sector organisations
- Multidisciplinary teams
- Experience with complex systems and operating structures
Services:
- Data protection consulting
- Privacy risk reviews
- Data governance assessments
- Technology and data risk
- Regulatory compliance
- Cyber security consulting
- Process and control reviews
- Data transformation
- Technology transformation
- Risk consulting
- Audit and assurance
Contact Information:
- Website: www.pwc.com
- Phone: +44 (0)14 1355 4000
- Address: 120 Bothwell Street, Glasgow, G2 7JS
- Instagram: www.instagram.com/pwc_uk
- Facebook: www.facebook.com/PwCUK
- LinkedIn: www.linkedin.com/company/pwc-uk
Deloitte
Deloitte is a professional services firm with practices covering audit, assurance, cyber security, data, technology, tax, legal and regulatory risk. Their work includes both focused advisory projects and wider programmes involving changes to systems, governance and business operations.
Data protection work draws on specialists from cyber, legal, risk, assurance and data teams. The scope depends on the organisation and the issues being reviewed, from privacy controls and regulatory duties to the way information is managed across technical systems and internal processes.
Key Highlights:
- Multidisciplinary UK professional services firm
- Privacy work supported by cyber, legal and risk teams
- Experience with complex operating models
- Services cover advisory, assurance and implementation
- Work across regulatory, technical and organisational areas
Services:
- Data protection reviews
- Privacy risk assessments
- Cyber security
- Risk and regulatory services
- Data governance
- Technology controls
- Legal advisory
- Assurance
- Internal control reviews
- Engineering, AI and data consulting
- Forensic services
Contact Information:
- Website: www.deloitte.com
- Address: 1 New Street Square, London EC4A 3HQ, United Kingdom
- Phone: +44 020 7936 3000
- Facebook: www.facebook.com/deloitteuk
- Twitter: x.com/deloitteuk
- LinkedIn: www.linkedin.com/company/deloitte
EY
EY provides assurance, consulting, tax, law and EY-parthenon strategy and transactions services. Their data protection and privacy work sits within Consulting and draws on expertise in technology, regulation, risk and business transformation.
Their teams review how privacy works across governance structures, business processes, technical systems and internal controls. Data protection is often considered alongside broader change programmes, including digital transformation, new technology adoption and updates to operating models.
Key Highlights:
- Multidisciplinary consulting and assurance firm
- Privacy work combines technology, legal and risk expertise
- Sector-focused teams
- Experience with business and technology change
- Work across governance, regulation and operational controls
Services:
- Data protection and privacy consulting
- Privacy risk assessments
- Data governance
- Regulatory compliance
- Technology risk
- Cyber security consulting
- Privacy operating model reviews
- Governance assessments
- Control reviews
- Legal advisory
- Business transformation
Contact Information:
- Website: www.ey.com
- Phone: +44 20 7951 2000
- Address: EY 6 More London Place London SE1 2DA
- Facebook: www.facebook.com/EY
- Twitter: x.com/EYnews
- LinkedIn: www.linkedin.com/company/ernstandyoung
RSM
RSM is an audit, tax and consulting firm working with organisations on financial, operational and regulatory matters. Their advisory work spans risk and governance, legal services, business transformation, forensic investigations, finance functions and people-related issues. They also publish practical guidance on current workplace and compliance questions, including data subject access requests and the use of AI in employee processes.
Their teams work by looking at the wider business rather than treating each issue in isolation. Governance, legal obligations, internal processes and technology often sit within the same engagement, particularly where an organisation is reviewing how information is handled across different departments. Their UK firms operate as independent members of the international RSM network.
Key Highlights:
- Audit, tax and consulting firm
- Risk and governance advisory practice
- Work across legal, operational and regulatory issues
- UK member of the RSM network
- Regular guidance on workplace data and DSAR matters
Services:
- Risk and governance
- Audit services
- Legal services
- Business transformation
- Forensic and investigation services
- People advisory
- Finance function support
- International services
Contact Information:
- Website: www.rsm.global
- Phone: +44 (0)161 830 4000
- Address: Landmark, St Peter's Square, 1 Oxford Street, Manchester, M1 4PB
- Facebook: www.facebook.com/GlobalRSM
- Twitter: x.com/RSM_Global
- LinkedIn: www.linkedin.com/company/rsm-uk
- Instagram: www.instagram.com/rsm.uk
Grant Thornton
Grant Thornton provides audit, assurance, tax, advisory and business consulting services from its Belfast office. They form part of Grant Thornton Ireland, with additional offices across Ireland, the Isle of Man, Gibraltar and Bermuda. Their clients include privately owned companies, listed businesses and public sector organisations.
Privacy and data protection work sits within their Business Risk Services practice. Their teams take time to understand how each organisation operates before reviewing its controls, responsibilities and exposure to regulatory risk. The work is delivered locally by the member firm, with access to technical and sector knowledge from the wider Grant Thornton network.
Key Highlights:
- Professional advisory and accountancy firm
- Privacy work within Business Risk Services
- Works with private, listed and public sector clients
Services:
- Privacy and data protection
- Business risk services
- Audit and assurance
- Advisory
- Tax
- Business consulting
- Governance and control reviews
- Regulatory risk advisory
Contact Information:
- Website: www.grantthornton.co.uk
- Phone: +44 (0)151 224 7200
- Address: Royal Liver Building Liverpool L3 1PS
- LinkedIn: www.linkedin.com/company/grant-thornton-uk
- Instagram: www.instagram.com/gt_trainees
Moore Kingston Smith
Moore Kingston Smith is a multidisciplinary advisory, tax and audit firm with offices in London and the South East. Their clients come from sectors including charities, education, financial services, healthcare, media, technology, real estate and professional services. They are also part of the Moore Global network, which gives their teams access to international expertise where an engagement crosses borders.
Data protection forms part of their risk advisory work. Their teams examine how organisations manage information, responsibilities and internal controls, then set out the gaps that require attention. The wider practice also covers digital transformation, third-party assurance, legal services, forensic accounting and outsourced business functions.
Key Highlights:
- Multidisciplinary advisory, tax and audit firm
- Offices across London and the South East
- Data protection within the risk advisory practice
- Experience across commercial and nonprofit sectors
- Member of the Moore Global network
Services:
- Data protection advisory
- Data protection reviews
- Risk advisory
- Governance and control assessments
- Third-party assurance
- Digital transformation
- Legal services
- Audit services
- Forensic accounting
- Outsourced accounting
Contact Information:
- Website: mooreks.co.uk
- Phone: +44 (0)20 4582 1000
- Address: 6th Floor, 9 Appold Street, London, EC2A 2AP
- Twitter: x.com/MooreKSLLP
- LinkedIn: www.linkedin.com/company/moore-kingston-smith
Forvis Mazars
Forvis Mazars provides audit, assurance, consulting, financial advisory, outsourcing and tax services. Their privacy and data protection work is delivered through the technology and digital consulting practice, with input from specialists in governance, internal controls and ICT risk. They work across industries including financial services, private equity, real estate, life sciences, manufacturing and the public sector.
Their consultants begin by understanding the organisation's systems, working methods and regulatory position. Reviews are then shaped around the actual privacy risks involved, rather than a standard package applied in the same way to every client. Their work covers the assessment of existing arrangements, the maturity of privacy controls and the technical steps needed to address identified gaps.
Key Highlights:
- Privacy practice within technology and digital consulting
- Governance and ICT risk expertise
- Reviews tailored to the organisation's operations
- Work across regulated and commercial sectors
- Focus on reducing disruption during compliance projects
Services:
- Privacy compliance reviews
- Data protection audits
- Maturity assessments
- GDPR advisory
- Technical implementation
- DPO support
- Privacy strategy assessments
- Governance and internal control reviews
- ICT risk management
Contact Information:
- Website: www.forvismazars.com
- Phone: +44(0) 161 238 9200
- Address: One St Peters Square, Manchester, M2 3DE, United Kingdom
- Twitter: x.com/ForvisMazarsUK
- LinkedIn: www.linkedin.com/company/forvis-mazars-in-the-uk
- Instagram: www.instagram.com/forvismazarsuk
WorkNest
WorkNest is a risk and compliance services group combining specialist advisers, consultancy and technology. Their work covers employment law, HR, health and safety, cyber resilience, ISO certification and data protection. They support organisations of different sizes, from smaller employers to international businesses with more complex structures.
Their GDPR audit service takes a practical look at how personal data is managed across policies, systems and day-to-day processes. Work is carried out alongside the client's team, with findings explained in clear terms and followed by actions that the organisation can work through. Their wider group includes The DPO Centre, which provides specialist data protection services.
Key Highlights:
- Risk and compliance services group
- Combines consultants with specialist technology
- Data protection expertise within the wider WorkNest group
- ISO 27001 certified information security controls
- Works with small and complex organisations
- Practical, collaborative delivery model
Services:
- GDPR audits
- Data protection support
- DPO services
- Privacy compliance reviews
- Cyber resilience
- ISO certification support
- Employment law
- Human resources
- Health and safety
- Wider compliance services
Contact Information:
- Website: worknest.com
- Phone: 0345 226 8393
- E-mail: enquiries@worknest.com
- Address: Woodhouse, Church Lane, Aldford Chester CH3 6JD
- Facebook: www.facebook.com/WorkNestGroup
- LinkedIn: www.linkedin.com/company/worknest-group
Conclusion
Choosing a data protection audit provider usually comes down to the type of organisation, the complexity of its data use and how much practical involvement it needs. Some businesses want a focused GDPR review with a clear action plan. Others need wider input across cyber security, governance, legal risk, systems and staff training. The right choice is not necessarily the largest firm or the one with the longest service list. It is the provider whose way of working matches the organisation's actual gaps, structure and internal resources.
That is where this guide becomes useful. It brings together different types of providers and shows how their services, methods and areas of expertise vary. Instead of treating every firm as interchangeable, organisations can compare what each one actually does and narrow the field before starting conversations. A good audit should leave the business with more than a report. It should give the team a clearer view of its risks, responsibilities and next steps.