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CASS 5 Audit Сompanies in London: A Guide to Providers

For firms operating under the FCA’s client money rules, CASS 5 compliance is more than a regulatory requirement. It plays an important role in maintaining effective controls, protecting client assets and demonstrating sound governance to regulators and stakeholders alike.

London is home to a wide range of firms offering CASS audit and assurance services. These include global professional services networks, specialist regulatory advisors and chartered accountancy practices with experience supporting regulated businesses across the financial services sector.

This guide highlights a selection of companies providing CASS 5 audit services in London. Rather than ranking providers, the aim is to offer practical context on the firms operating in this area, the types of organisations they typically support, and the broader expertise they bring across governance, risk and regulatory compliance.

Acumon

Acumon is a UK firm of chartered accountants and registered auditors providing CASS 5 audit services to firms and organisations across London and the wider UK market.

The firm supports regulated businesses ranging from insurance intermediaries and brokers through to larger corporate groups operating within FCA-regulated environments. CASS 5 audit engagements are designed to assess compliance with client money rules, strengthen governance arrangements and support effective regulatory oversight.

Acumon provides CASS 5 audit support across a range of regulatory and reporting requirements, including client money assessments, control reviews, compliance testing and reporting obligations under the FCA Client Assets Sourcebook (CASS). Services are delivered using a structured, risk-based approach tailored to the scale and complexity of each regulated entity.

Acumon holds a Public Interest Entity (PIE) audit licence, enabling the firm to support organisations subject to enhanced regulatory oversight in the United Kingdom. In addition to its UK statutory audit registration, the firm also maintains audit licences in the Cayman Islands, British Virgin Islands (BVI), Jersey and Isle of Man, supporting organisations operating across international structures and reporting environments.

Regulated firms handling client money often face increasingly complex compliance requirements involving governance oversight, control frameworks and evolving FCA expectations. Acumon works with finance teams, compliance functions and senior management to support regulatory compliance, reporting accuracy and effective control environments.

CASS 5 Audit Capabilities

Acumon provides CASS 5 audit services across a range of regulated entities and compliance environments.

These include:

  • insurance intermediaries and brokers
  • FCA-regulated firms handling client money
  • organisations subject to CASS 5 requirements
  • multi-entity and group structures
  • businesses with cross-border operations
  • regulated entities with complex control frameworks

CASS 5 engagements are led by experienced professionals with direct involvement throughout the audit and reporting process.

Regulatory Licences and Registrations

Acumon maintains a range of regulatory registrations and professional authorisations supporting organisations operating across UK and international environments.

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 support organisations operating across multiple jurisdictions, regulated sectors and international group structures.

Core Services

Alongside CASS 5 audit services, Acumon provides a wider range of services supporting governance, reporting and regulatory compliance.

These include:

  • CASS 5 audits and compliance reviews
  • client money control assessments
  • statutory external audit
  • group and subsidiary audits
  • Public Interest Entity (PIE) audits
  • charity and not-for-profit audit
  • internal audit and governance reviews
  • risk management and compliance support

CASS 5 engagements are often delivered alongside discussions regarding client money controls, governance frameworks, regulatory reporting and internal oversight procedures.

As regulated businesses expand operations or introduce more complex operating structures, compliance obligations and control requirements often require increased oversight and documentation.

Acumon works with businesses that are:

  • managing client money under CASS 5 rules
  • preparing for FCA regulatory reviews
  • operating within group structures
  • reviewing governance and control procedures
  • expanding regulated activities

Early engagement can help organisations strengthen compliance frameworks, improve control environments and support ongoing regulatory obligations.

Contact Information:

BKL

BKL provides CASS audit services for FCA-regulated firms that hold or control client money and assets. Their work covers several areas of the Client Assets Sourcebook, including CASS 5 audits for insurance intermediaries. Alongside the audit process itself, they review systems and controls to help firms understand how client money arrangements operate in practice and where gaps may exist in compliance processes.

CASS requirements often sit alongside broader governance and assurance obligations, particularly for firms operating in regulated financial markets. BKL’s financial services audit specialists support businesses across different stages of growth, including fintech companies, by combining CASS audits with wider audit engagements where appropriate. Their approach includes coordination with regulatory advisers and legal specialists when firms face more complex regulatory requirements.

Key Highlights:

  • Experience supporting FCA-regulated businesses
  • CASS 5 audit services for insurance firms
  • Coverage across multiple CASS categories, including CASS 6, 7 and 8
  • Support for Limited Assurance Reports and Reasonable Assurance Reports
  • Experience working with fintech businesses and regulated financial services firms
  • Audit work linked to systems, controls and regulatory compliance
  • Preparation for evolving safeguarding requirements under CASS 15

Services:

  • CASS 5 audits for insurance intermediaries
  • Client money assurance engagements
  • Limited Assurance Reports (LARs)
  • Reasonable Assurance Reports (RARs)
  • CASS compliance reviews
  • Systems and controls assessments
  • Regulatory audit support
  • Safeguarding audit preparation

Contact Information:

  • Website: bkl.co.uk
  • Twitter: x.com/BKLtweets
  • LinkedIn: www.linkedin.com/company/berg-kaprow-lewis-llp
  • Address: First floor, 5 Fleet Place, London EC4M 7RD
  • Phone: +44 (0)20 7832 0444

Price Bailey

Price Bailey carries out CASS audits for firms regulated by the FCA that hold client money or custody assets. Their work covers businesses operating under CASS 5, CASS 6 and CASS 7 requirements, including insurance distributors, investment firms and payment-related businesses. Audit engagements are structured around understanding a firm’s control environment and assessing whether client money arrangements meet regulatory expectations.

The firm places particular attention on reconciliations, acknowledgement letters and breach identification, all of which remain areas of interest for the regulator. Their audit process includes reviewing operating controls, testing transactions and assessing how firms manage client asset protections on an ongoing basis. With regulatory requirements continuing to evolve, especially for safeguarding arrangements, CASS compliance remains closely linked to wider governance and risk management frameworks.

Key Highlights:

  • CASS audit services for FCA-regulated firms
  • Experience across insurance, investment and payment sectors
  • Coverage of CASS 5, CASS 6 and CASS 7 requirements
  • Assessment of client money controls and reconciliations
  • Support for limited, reasonable and hybrid assurance engagements
  • Focus on breach identification and regulatory reporting
  • Knowledge of safeguarding developments affecting regulated firms

Services:

  • CASS 5 audits for insurance businesses
  • Limited assurance engagements
  • Reasonable assurance engagements
  • Hybrid assurance reports
  • Client money reconciliations review
  • Control environment assessments
  • CASS mapping exercises
  • Regulatory compliance testing

Contact Information:

  • Website: www.pricebailey.co.uk
  • Email: city@pricebailey.co.uk
  • Facebook: www.facebook.com/PriceBaileyLLP
  • Twitter: x.com/price_bailey
  • LinkedIn: www.linkedin.com/company/price-bailey
  • Instagram: www.instagram.com/pbpeople
  • Address: 8th Floor, Dashwood House, 69 Old Broad Street, London, EC2M 1QS
  • Phone: 020 7065 2660 

MAH

MAH has experience supporting financial services firms with CASS audits, particularly in relation to CASS 5 and CASS 7 client money rules. Their client base includes insurance brokers, foreign exchange businesses, wealth managers and other FCA-authorised firms where safeguarding client money forms part of day-to-day operations. Audit work is built around understanding how firms manage transactions, reconciliations and client balances within their regulatory framework.

The audit process typically involves reviewing systems, testing transactions and documenting any issues identified during the engagement. Given the importance of accurate client money calculations and record keeping, firms operating under CASS requirements often need clear evidence that controls function as intended. MAH’s work in this area reflects the close relationship between compliance, operational processes and regulatory oversight.

Key Highlights:

  • Experience with CASS 5 and CASS 7 audits
  • Work with FCA-authorised financial services firms
  • Coverage of both limited and reasonable assurance engagements
  • Experience across insurance, FX and wealth management sectors
  • Review of reconciliations and client money controls
  • Audit reporting through FCA Connect
  • Focus on identifying and documenting breaches

Services:

  • CASS 5 audits for insurance intermediaries
  • CASS 7 audits
  • Reasonable assurance audits
  • Limited assurance reviews
  • Client money testing
  • Transaction walkthroughs
  • Reconciliation reviews
  • Breach reporting and documentation

Contact Information:

  • Website: www.mah.uk.com
  • Email: enquiries@mah.uk.com
  • Facebook: www.facebook.com/p/MAH-Chartered-Accountants-100068129359509
  • LinkedIn: www.linkedin.com/company/mah-chartered-accountants
  • Instagram: www.instagram.com/mahca2011
  • Address: 2nd Floor, 154 Bishopsgate, London, EC2M 4LN
  • Phone: 0207 100 3610

Menzies

Menzies provides audit and assurance services to businesses operating in regulated sectors, including firms subject to the FCA’s client money rules. Their work in the CASS area includes assurance services linked to client money reconciliations, an important element of CASS 5 compliance for mortgage and insurance firms. The firm publishes guidance on how regulated businesses can maintain accurate records and ensure that client money requirements align with available resources.

Client money oversight remains a key part of the wider regulatory framework, particularly where firms handle funds on behalf of customers. Menzies highlights the importance of reconciliation processes, record retention and governance arrangements that support ongoing compliance. Their experience across financial services and statutory audit engagements places CASS reviews within a broader context of risk management and regulatory assurance.

Key Highlights:

  • Experience supporting FCA-regulated firms
  • Focus on client money reconciliations under CASS 5
  • Audit and assurance capabilities across regulated sectors
  • Guidance on client money calculations and record keeping
  • Support for governance and compliance processes
  • Experience in financial services assurance
  • Coverage of regulatory requirements linked to client assets

Services:

  • CASS assurance services
  • Client money reconciliations review
  • Regulatory compliance support
  • Statutory audit
  • Audit and assurance engagements
  • Financial services assurance
  • Governance reviews
  • Risk and compliance assessments

Contact Information:

  • Website: www.menzies.co.uk
  • LinkedIn: www.linkedin.com/company/menzies-llp
  • Instagram: www.instagram.com/menzies_llp
  • Address: 4th Floor, 95 Gresham Street, London, EC2V 7AB 
  • Phone: +44 (0)20 7387 5868

Johnston Carmichael

Johnston Carmichael offers audit and assurance services to businesses operating in changing regulatory environments, including firms affected by the FCA’s Client Assets Sourcebook. Their CASS audit services are designed to support organisations dealing with client asset and client money requirements, particularly where growth, market entry or changes in business activities introduce additional compliance obligations.

As financial services firms continue to adapt to evolving regulations, CASS oversight often extends beyond annual audits and into wider control frameworks. Johnston Carmichael combines CASS support with expertise in internal audit, IT assurance and financial reporting, reflecting the increasing connection between governance, operational resilience and regulatory expectations. This broader perspective can be particularly relevant for firms managing complex systems and customer assets. 

Key Highlights:

  • CASS audit services for regulated businesses
  • Experience supporting firms in evolving regulatory environments
  • Expertise in audit, assurance and financial reporting
  • Integration of IT assurance and control reviews
  • Focus on governance and operational resilience
  • Support for businesses at different stages of growth
  • Experience across multiple sectors

Services:

  • CASS audits
  • Internal audit services
  • IT audit and assurance
  • Financial reporting advisory
  • Risk assurance
  • Control effectiveness reviews
  • Regulatory compliance support
  • Audit and assurance services

Contact Information:

  • Website: johnstoncarmichael.com
  • Facebook: www.facebook.com/JohnstonCarmichael
  • Twitter: x.com/JC_Accountants
  • LinkedIn: www.linkedin.com/company/johnston-carmichael-chartered-accountants-and-business-advisers
  • Instagram: www.instagram.com/johnston_carmichael
  • Address: 20 Birchin Lane, London, EC3V 9DU 
  • Phone: 0203 7144 350

Thistle Initiatives

Thistle Initiatives specialises in regulatory consulting and compliance support for firms operating under FCA supervision. Their work around CASS focuses on helping businesses understand and maintain compliance with client money and custody asset requirements across sectors such as investments, insurance, credit and digital assets. Support is available both before and after external audits, reflecting the ongoing nature of CASS compliance.

CASS frameworks often require more than periodic reviews, particularly as firms grow or adapt to changing regulations. Thistle Initiatives carries out health checks, reviews internal procedures and assists with remediation where issues have been identified. Their services are closely linked to governance, risk management and compliance monitoring, which are central to maintaining effective client asset controls.

Key Highlights:

  • Focus on FCA compliance and regulatory consulting
  • Support across investments, insurance and digital assets sectors
  • CASS health check and review services
  • Assistance before and after external audits
  • Experience with compliance monitoring and reporting
  • Review of controls and governance processes
  • Support for remediation and corrective actions

Services:

  • CASS health check audits
  • CASS compliance reviews
  • External audit preparation
  • Review of CASS procedures
  • CASS risk matrix assessments
  • CASS reporting support
  • CMAR reviews
  • Remediation assistance following audit findings

Contact Information:

  • Website: www.thistleinitiatives.co.uk
  • LinkedIn: www.linkedin.com/company/thistle-initiatives
  • Address: 2nd Floor, 4 St. Paul’s Churchyard, London, England, EC4M 8AY
  • Phone: 020 7436 0630

FSCom

FSCom focuses on regulatory compliance and assurance services for firms operating under UK and EEA financial regulations. Their work includes support across the Client Assets Sourcebook, where CASS compliance remains a key area for firms handling client money and assets. In the context of CASS 5, this can involve assessing controls, reviewing processes and helping businesses understand whether their arrangements meet regulatory expectations.

As regulatory frameworks continue to evolve, CASS oversight has become closely linked with governance, risk management and operational resilience. FSCom’s background in compliance and audit allows them to assist firms with remediation, control testing and ongoing assurance activities. Their experience spans several regulated sectors, including payments and financial services.

Key Highlights:

  • Focus on regulatory compliance and assurance
  • Experience with FCA and EEA regulatory frameworks
  • Support for CASS compliance and remediation
  • Expertise across governance and control frameworks
  • Experience in payments and financial services sectors
  • Audit and assurance services linked to regulatory requirements
  • Coverage of client asset protection obligations

Services:

  • CASS compliance reviews
  • Regulatory audits
  • Remediation support
  • Control framework assessments
  • Compliance monitoring
  • Risk assessments
  • Safeguarding reviews
  • Governance assurance

Contact Information:

  • Website: fscom.co
  • Email: info@fscom.co
  • Twitter: x.com/fscom1
  • LinkedIn: www.linkedin.com/company/fscom-limited
  • Address: 46 New Broad Street, London
EC2M 1JH
  • Phone: +44 (0) 20 3327 7337

Lighthouse Consultants

Lighthouse Consultants provides CASS audit services aimed at helping firms demonstrate compliance with the FCA’s client money rules. Their published materials highlight the role of audits in safeguarding client funds and maintaining effective controls, which are central elements of CASS 5 requirements for insurance intermediaries and other regulated firms.

Client money oversight is often more than an annual exercise, particularly where businesses need to monitor controls on an ongoing basis. Lighthouse Consultants emphasises transparency, risk reduction and regulatory compliance as part of the audit process, reflecting the broader governance responsibilities associated with managing client assets.

Key Highlights:

  • Experience performing CASS audits
  • Focus on client money protection
  • Support for FCA compliance requirements
  • Attention to control frameworks and transparency
  • Emphasis on risk identification and mitigation
  • Coverage of client money management processes
  • Alignment with regulatory expectations

Services:

  • CASS audits
  • Client money reviews
  • Control framework assessments
  • Compliance assurance
  • Risk identification
  • Regulatory support
  • Audit preparation
  • Governance reviews

Contact Information:

  • Website: lighthc.london
  • Email: info@lighthc.london
  • Address: Fitzrovia, 60 Tottenham Court Road, London, W1T 2EW
  • Phone: +44 207 871 0485

Wisteria Accountants

Wisteria Accountants offers CASS and client money audit services for businesses regulated by the FCA. Their approach centres on examining how client money is handled, whether controls are operating effectively and if existing arrangements align with regulatory obligations. This area is particularly relevant for firms subject to CASS 5 requirements, where protecting client funds remains a core expectation.

Handling client money can involve complex processes that change as firms grow or introduce new services. Wisteria Accountants review these arrangements to identify gaps, assess safeguards and provide observations on areas that may require attention. The audit process is positioned within the wider context of compliance, accountability and maintaining confidence in financial operations.

Key Highlights:

  • CASS and client money audit services
  • Focus on client money controls
  • Assessment of regulatory compliance
  • Review of safeguards protecting client funds
  • Experience with FCA-regulated businesses
  • Audit work linked to governance processes
  • Support for identifying control weaknesses

Services:

  • CASS 5 audits
  • Client money audits
  • Control testing
  • Compliance reviews
  • Safeguarding assessments
  • Audit reporting
  • Risk assessments
  • Regulatory assurance

Contact Information:

  • Website: wisteria.co.uk
  • Facebook: www.facebook.com/WisteriaAccountants
  • Twitter: x.com/wisterialtd
  • LinkedIn: www.linkedin.com/company/wisteria-limited
  • Address: The Grange Barn, Pike’s End, Pinner, London, HA5 2EX
  • Phone: 020 4546 7630

Forvis Mazars

Forvis Mazars provides CASS and safeguarding services to firms operating across financial services, including insurance, banking, asset management and payment sectors. Their CASS work is closely linked to governance, internal controls and regulatory oversight, reflecting the FCA’s continued focus on client asset protection. For businesses subject to CASS 5 requirements, this includes reviewing how client money is managed, recorded and reconciled within broader control frameworks.

Regulatory expectations around client assets have expanded significantly over time, particularly in areas such as IT systems, record keeping and oversight processes. Forvis Mazars draws on audit, risk and technology expertise to assess how firms maintain compliance in practice and how systems support accurate client money management. Their approach extends beyond annual assurance by helping organisations identify control gaps and address areas requiring remediation.

Key Highlights:

  • Experience across regulated financial services sectors
  • CASS and safeguarding expertise
  • Focus on governance and control frameworks
  • Assessment of client asset protection arrangements
  • Integration of audit and technology specialists
  • Support with control gap identification
  • Experience with evolving regulatory requirements

Services:

  • CASS 5 audits
  • Safeguarding reviews
  • Assurance engagements
  • Control framework assessments
  • IT control reviews
  • Compliance testing
  • Risk assessments
  • Remediation support

Contact Information:

  • Website: www.forvismazars.com
  • Twitter: x.com/ForvisMazarsUK
  • LinkedIn: www.linkedin.com/company/forvis-mazars-in-the-uk
  • Instagram: www.instagram.com/forvismazarsuk
  • Address: 30 Old Bailey, London, EC4M 7AU, United Kingdom
  • Phone: +44 (0) 20 7063 4000

CASS Audit Services

CASS Audit Services specialises in assurance and advisory work relating to the FCA’s Client Assets Sourcebook. Their activities cover external and internal CASS reviews, with a focus on helping regulated firms maintain effective oversight of client money and related controls. While their published expertise spans multiple CASS chapters, the principles applied to CASS 5 engagements remain centred on compliance, monitoring and protection of client assets.

Many firms now view CASS compliance as an ongoing process that requires coordination between operations, compliance and independent oversight functions. CASS Audit Services supports this through risk-based reviews, third-line monitoring and consultancy work linked to regulatory change and control enhancements. This can be particularly relevant where firms introduce new products, systems or operating models that affect client money arrangements.

Key Highlights:

  • Focus on CASS assurance and advisory services
  • Experience with external and internal CASS reviews
  • Risk-based approach to compliance monitoring
  • Support for independent third-line oversight
  • Knowledge of regulatory developments
  • Experience with remediation and control enhancements
  • Coverage across multiple CASS areas

Services:

  • CASS 5 audits
  • External CASS audits
  • Internal CASS reviews
  • Compliance monitoring
  • Third-line assurance
  • CASS consultancy
  • Control reviews
  • Remediation support

Contact Information:

  • Website: cassauditservices.co.uk
  • Email: talis@cassauditservices.co.uk
  • Address: 43 Eastbourne Road, London, TW8 9PF, UK
  • Phone: +44 (0) 7733808503

Conclusion

Choosing a CASS 5 audit provider in London is not simply about meeting an annual regulatory requirement. For insurance intermediaries and other FCA-regulated firms, CASS compliance forms part of a broader framework of governance, risk management and client money protection. As regulatory expectations continue to evolve, firms often look for advisers who understand both the technical requirements of the Client Assets Sourcebook and the practical realities of operating in regulated markets.

The companies featured in this guide represent a range of approaches to CASS 5 audits, from specialist compliance consultancies to established audit and assurance firms. Some place greater emphasis on regulatory advisory and remediation, while others integrate CASS work into wider audit, risk and governance services. The most suitable provider will often depend on a firm’s business model, regulatory permissions and the complexity of its client money arrangements.

When assessing potential providers, organisations typically consider factors such as experience with FCA-regulated businesses, understanding of client money controls, reporting capabilities and familiarity with evolving regulatory requirements. A well-executed CASS 5 audit can do more than support compliance – it can help firms strengthen controls, improve oversight and maintain confidence in how client assets are managed.