This practical guide looks at companies offering data protection audit services in London, with a focus on their expertise, service scope, and typical client needs. It is an overview rather than ranking companies by a single standard, since requirements can vary considerably between organisations. The selection includes larger companies with broad risk, compliance, and assurance capabilities alongside narrower specialists focused primarily on privacy and data protection. Each profile provides context on the company, the clients it serves, and the areas that distinguish its data protection work. The aim is to make comparison easier and give readers a clearer basis for choosing a suitable company.

Acumon
Acumon is a UK firm of chartered accountants and registered auditors providing data protection audit services to companies and organisations from its London practice.
The firm works with businesses ranging from growing owner-managed companies through to larger corporate groups and regulated organisations. Data protection audit engagements focus on assessing whether documented privacy frameworks reflect the way personal data is actually collected, stored, accessed, shared, retained, and protected in day-to-day operations.
Acumon’s GDPR and data protection audit work examines compliance with UK GDPR requirements across areas such as records of processing activities, lawful bases, privacy notices, data subject rights, retention, security, breach management, processor relationships, international transfers, cookies, and PECR. The audit is designed to identify gaps between formal policies and operational practice and to prioritise findings according to regulatory and commercial risk.
Data protection responsibilities frequently extend beyond the privacy function. Personal information may sit across HR systems, customer platforms, marketing tools, finance applications, cloud services, and third-party suppliers. Reviewing these environments requires an understanding of governance, information security, technology controls, and third-party risk alongside the core requirements of UK data protection law.
Acumon provides data protection audit services as part of its wider Risk and Technology Assurance practice. This enables organisations to connect privacy compliance with related areas including IT risk, cyber security, internal controls, governance, and business continuity where these issues overlap.
The firm’s London team works with management, boards, compliance functions, and technology teams to assess current controls and establish practical remediation priorities. Data protection audits can be relevant before customer due diligence, following changes to systems or suppliers, after organisational growth, or where existing GDPR documentation has not been reviewed for some time.
Data Protection Audit Capabilities
Acumon provides data protection audit services across a range of governance, operational, and technology areas.
These include:
- UK GDPR Governance And Accountability
- Records Of Processing Activities
- Lawful Bases And Privacy Notices
- Data Subject Rights And DSAR Processes
- Data Retention And Deletion Controls
- Security And Personal Data Access Controls
- Personal Data Breach Procedures
- Processor And Supplier Arrangements
- International Data Transfer Controls
- Cookies, Marketing And PECR Compliance
Audit findings can be graded according to risk and supported by a prioritised remediation plan for management and governance teams.
Regulatory Licences and Registrations
Acumon holds professional registrations that support its wider audit and assurance activities in the UK.
These include:
- UK Statutory Audit Registration
- ICAEW Registered Audit Firm Status
- Public Interest Entity Audit Capability
These registrations relate to Acumon’s broader regulated audit practice. Data protection audits sit within its Risk and Technology Assurance work and are focused on assessing privacy governance, controls, and compliance rather than providing a statutory financial audit opinion.
Core Services
In addition to data protection audit services, Acumon provides a range of risk, technology, governance, and assurance services.
These include:
- GDPR And Data Protection Audits
- Cyber Security Audits
- IT Risk Audit And Assurance
- IT General Controls Reviews
- Internal Audit And Risk Assurance
- Corporate Governance Reviews
- Risk Management Audit And Advisory
- Business Continuity And Technology Risk Reviews
Data protection reviews can be particularly relevant where organisational change has created a gap between existing GDPR documentation and current processing activities.
Acumon works with businesses that are:
- Introducing New Systems Or Cloud Platforms
- Changing Suppliers And Data Processors
- Expanding Personal Data Processing Activities
- Preparing For Customer Or Investor Due Diligence
- Reviewing Compliance Following Organisational Growth
- Strengthening Privacy And Information Governance Controls
Early review of data protection arrangements can help identify weaknesses in governance, retention, access, supplier management, and rights-handling processes before they develop into wider regulatory or operational issues.
Contact Information
- Website: acumon.com
- Phone: 020 8567 3451
- Email: [email protected]
- Address: 1-2 Craven Road, Ealing, London, W5 2UA, UK

Evalian
Evalian combines data protection consultancy with cyber security, ISO and outsourced privacy services. GDPR consultancy sits within a broader privacy and security practice, allowing organisations to look at legal compliance and information security in the same engagement where appropriate.
Its data protection work includes compliance assessments, data mapping, DPIAs, privacy governance and outsourced DPO support. The company can therefore suit organisations that need more than a policy review and want privacy requirements considered alongside technical security or ISO 27001 arrangements. Its published services and client work show support for organisations across sectors including technology, finance, education and healthcare.
Key Facts
- Core services: GDPR Consultancy, Privacy Reviews, DPIAs, Outsourced DPO, Cyber Security
- Specialization: Combined Privacy And Information Security Support
- Relevant areas: Data Governance, Risk Assessments, Regulatory Compliance
- Service coverage: UK
- Related capabilities: ISO Consultancy And Penetration Testing
Contact Information
- Website: evalian.co.uk
- Phone: 03330 500 111
- Email: [email protected]
- Address: Blackwell House, Guildhall Yard, London, EC2V 5AE
- LinkedIn: www.linkedin.com/company/evalian

PwC
PwC approaches data protection through a multidisciplinary technology, data and risk practice. Its UK data protection and privacy services address both regulatory compliance and the broader governance questions surrounding how information is identified, secured, accessed and used.
Relevant work includes GDPR accountability, privacy assurance reporting, management of data subject rights, personal data breach readiness and data governance. This wider scope can be useful where a privacy audit forms part of a larger transformation, technology programme or enterprise risk review rather than an isolated compliance exercise.
Key Facts
- Core services: Data Protection, Privacy Advisory, Governance And Assurance
- Specialization: Large And Complex Data Environments
- Relevant areas: GDPR Accountability, Data Security, Data Subject Rights
- Additional capabilities: Data Governance, Technology Risk, Cyber Security
- Location: London And Wider UK Market
Contact Information
- Website: www.pwc.co.uk
- Phone: +44 (0)20 7583 5000
- Address: 1 Embankment Place, London, WC2N 6RH, United Kingdom
- LinkedIn: www.linkedin.com/company/pwc-uk
- Facebook: www.facebook.com/PwCUK
- Instagram: www.instagram.com/pwc_uk

Moore Kingston Smith
Moore Kingston Smith provides data protection services through its risk advisory practice. Its offering includes retained privacy support as well as individual projects focused on specific compliance questions or organisational changes.
Data protection audits and gap assessments form part of its published project work. The team can also assist with DSARs, breaches, outsourced DPO arrangements and readiness for organisations entering UK or EU markets. This makes the service relevant where an audit needs to connect with continuing data protection management rather than end with a findings report. The practice has a London office at Appold Street.
Key Facts
- Core services: Data Protection Audits, Gap Assessments, DPO Services
- Specialization: Risk Advisory And Ongoing Privacy Governance
- Relevant areas: UK, EU And International Data Protection
- Additional services: DSAR Support, Breach Advice, Market Entry Readiness
- Location: London, UK
Contact Information
- Website: mooreks.co.uk
- Phone: +44 (0)20 4582 1000
- Address: 6th Floor, 9 Appold Street, London, EC2A 2AP
- LinkedIn: www.linkedin.com/company/moore-kingston-smith
- Twitter: x.com/MooreKSLLP

Grant Thornton UK
Grant Thornton brings data protection work into its wider risk and resilience practice. Its published GDPR materials describe support across data protection assurance, compliance reviews, control frameworks and privacy governance.
Relevant engagements can include gap analysis, identification of processes and risks affecting personal data, development of risk and control frameworks, GDPR audits and reviews of existing compliance programmes. This broader assurance background can be useful for organisations that want privacy controls assessed alongside governance, cyber resilience or internal risk management. Grant Thornton’s UK registered office is in London.
Key Facts
- Core services: GDPR Audits, Gap Analysis, Compliance Reviews
- Specialization: Risk, Resilience And Data Protection Assurance
- Relevant areas: Privacy Controls, Governance, Policies And Procedures
- Additional capabilities: Cyber Resilience And Risk Management
- Location: London, UK
Contact Information
- Website: www.grantthornton.co.uk
- Phone: +44 (0)20 7383 5100
- Address: 8 Finsbury Circus, London, EC2M 7EA
- LinkedIn: www.linkedin.com/company/grant-thornton-uk
- Instagram: www.instagram.com/gt_trainees

WorkNest
WorkNest includes GDPR auditing within a broader set of compliance and business risk services. Its GDPR audit service uses a consultant-led review to assess an organisation’s current level of compliance rather than relying solely on a self-assessment questionnaire.
The audit requires access to relevant staff, documents and evidence, with findings recorded in a report identifying areas of non-conformity. WorkNest also offers GDPR gap analysis and privacy advisory support, giving businesses options depending on whether they need a formal review or ongoing help with data protection questions.
Key Facts
- Core services: GDPR Audit, GDPR Gap Analysis, Privacy Advisory
- Specialization: Operational Compliance Reviews
- Audit approach: Evidence And Documentation Review
- Output: Findings And Identified Non-Conformities
- Service coverage: UK
Contact Information
- Website: worknest.com
- Phone: 0345 226 8393
- Email: [email protected]
- Address: Woodhouse, Church Lane, Aldford Chester CH3 6JD
- LinkedIn: www.linkedin.com/company/worknest-group
- Facebook: www.facebook.com/WorkNestGroup

EY
EY provides data protection and privacy services through its consulting and cybersecurity capabilities. The practice addresses privacy across the full information lifecycle, connecting regulatory compliance with questions around data security, governance and acceptable use.
Its published privacy services include privacy assessments, transformation support and GDPR compliance. EY also provides tools and advisory services aimed at evaluating privacy risks associated with how organisations use data. This can be relevant to larger businesses where an audit or assessment needs to consider enterprise systems, new technologies and changing uses of personal information.
Key Facts
- Core services: Privacy Assessments, GDPR Compliance, Privacy Transformation
- Specialization: Enterprise Data Protection And Cybersecurity
- Relevant areas: Data Lifecycle, Regulatory Compliance, Privacy Risk
- Additional capabilities: Technology And Cyber Risk
- Service coverage: London And Wider UK Market
Contact Information
- Website: www.ey.com
- Phone: +44 20 7951 2000
- Address: 1 More London Place, London SE1 2AF
- LinkedIn: www.linkedin.com/company/ernstandyoung
- Facebook: www.facebook.com/EY
- Twitter: x.com/EYnews

Clarkslegal
Clarkslegal provides privacy and data protection support from a legal and regulatory perspective. Its GDPR audit work is intended to help organisations understand where existing policies, controls and practical data handling arrangements may not meet applicable requirements.
A legal-led approach can be particularly relevant where audit findings are likely to require changes to contracts, privacy documentation, internal policies or responses to data subject requests. Its broader data protection work covers compliance advice, breach matters, privacy documentation and subject access issues, allowing identified audit gaps to move directly into legal remediation where required.
Key Facts
- Core services: Data Protection Audits, GDPR Health Checks, Gap Analysis
- Specialization: Legal And Regulatory Privacy Support
- Relevant areas: Privacy Documentation, Contracts, SARs, Data Breaches
- Audit approach: Governance And Compliance Review
- Service coverage: UK
Contact Information
- Website: clarkslegal.com
- Phone: +442075398000
- Email: [email protected]
- Address: Chancery House, 53-64 Chancery Lane, London, WC2A 1QS
- LinkedIn: www.linkedin.com/company/clarkslegal-llp

Data Privacy Advisory Service
Data Privacy Advisory Service, commonly referred to as DPAS, focuses on privacy compliance and outsourced data protection support. Its services address the governance and practical processes organisations need to manage personal information under UK data protection rules.
Audit and assessment work can help identify gaps between regulatory requirements, internal documentation and operational practice. The wider service model can then support remediation through consultancy, policy work, DPO assistance and ongoing privacy management. This makes the provider relevant where the organisation expects compliance work to continue after the initial assessment.
Key Facts
- Core services: GDPR Reviews, Data Protection Consultancy
- Specialization: Privacy Compliance And Governance
- Relevant areas: Policies, Processes, Accountability
- Additional services: Ongoing Privacy And DPO Support
- Service coverage: UK
Contact Information
- Website: www.dataprivacyadvisory.com
- Phone: 0203 3013384
- Email: [email protected]
- LinkedIn: www.linkedin.com/company/data-privacy-advisory-service
- Facebook: www.facebook.com/DataProtectionAdvisoryService
- Instagram: www.instagram.com/dataprivacyadvisoryservice

Boardroom Matters
Boardroom Matters provides legal and governance support that includes data protection compliance work. Its London presence makes it particularly relevant to the geographic focus of this guide.
The service can support organisations assessing current privacy arrangements, reviewing data protection documentation and addressing governance weaknesses identified through compliance work. The legal perspective is useful where data protection concerns overlap with board responsibilities, contracts, organisational policies or wider corporate governance requirements rather than being treated solely as an information security problem.
Key Facts
- Core services: Data Protection Compliance And Legal Support
- Specialization: Governance And Corporate Legal Matters
- Relevant areas: Privacy Documentation And Compliance
- Client context: Companies Requiring Legal And Governance Support
- Location: London, UK
Contact Information
- Website: boardroommatters.co.uk
- Phone: +44 (0)203 733 6443
- Email: [email protected]
- Address: 71-75 Shelton Street, London WC2H 9JQ

Deloitte
Deloitte combines audit, risk, cyber and technology capabilities within a large professional services environment. Data protection issues can therefore be addressed in the context of wider internal controls, technology systems, business transformation and regulatory requirements.
This model is more relevant to organisations with complex operating structures or interconnected compliance programmes than to businesses seeking only a limited review of privacy documents. Deloitte LLP is headquartered at New Street Square in London, giving the company a direct presence within the market covered by this guide. Its own UK privacy framework references GDPR, the Data Protection Act 2018 and protection of information used during client service delivery.
Key Facts
- Core capabilities: Risk, Audit, Cybersecurity And Technology Advisory
- Relevant areas: Privacy, Information Governance And Regulatory Risk
- Client context: Complex And Larger Organisations
- Additional capabilities: Controls, Cyber Risk And Technology Assurance
- Location: London, UK
Contact Information
- Website: www.deloitte.com
- Phone: +44 (0)20 7936 3000
- Address: 1 New Street Square, London, EC4A 3HQ, United Kingdom
- LinkedIn: www.linkedin.com/company/deloitte
- Facebook: www.facebook.com/deloitteuk
- Twitter: x.com/deloitteuk
- Instagram: www.instagram.com/deloitte_uk
Conclusion
Choosing between data protection audit companies in London depends on business size, sector, the maturity of existing processes, and the regulatory requirements an organisation needs to address. Some companies combine data protection reviews with wider risk, cyber security, governance, and assurance services, while others concentrate more narrowly on privacy compliance and GDPR. That difference matters when deciding whether a focused assessment or a broader integrated review is more appropriate. This guide is intended to provide neutral context for comparing those approaches rather than presenting one model as universally preferable. A suitable partner should provide independent assurance while translating identified weaknesses into practical actions that reduce risk and strengthen organisational resilience.