CASS 6 Audit Firms in Birmingham: Provider Guide

Choosing a CASS 6 audit provider in Birmingham is not just another compliance step for FCA-regulated firms. Where custody assets are involved, the audit can affect how clearly a business understands its controls, records, governance, and readiness for regulatory scrutiny.

Birmingham businesses may work with a range of audit and assurance providers, from larger accountancy networks with financial services experience to specialist firms that focus on FCA client asset requirements. Each provider can bring a different mix of CASS knowledge, sector familiarity, reporting style, and practical support.

This guide highlights a selection of CASS 6 audit companies serving firms in and around Birmingham. It is not intended as a strict ranking. The aim is to give useful context – who these firms are, the types of regulated businesses they may support, and the service areas most relevant to firms with custody asset obligations.

Acumon

Acumon is a UK-based firm of chartered accountants and registered auditors that supports companies, charities, regulated businesses, and international groups with external audit and related assurance work.

For firms reviewing CASS 6 audit companies in Birmingham, Acumon brings experience in audit work for regulated organisations where client asset protection, governance, record keeping, and internal control quality are important parts of the engagement. CASS 6 applies to safe custody assets, so the audit focus is often on how assets are held, recorded, reconciled, controlled, and protected within the firm’s operating model.

The firm works with a broad client base, including growing owner-managed companies, charities, larger corporate groups, and organisations with regulatory obligations. Its audit work follows a structured, risk-led methodology and is carried out in line with International Standards on Auditing (UK).

Acumon is licensed to carry out Public Interest Entity (PIE) audit work in the UK. This allows the firm to act for listed companies and other organisations that fall under higher levels of regulatory scrutiny. PIE audits come with additional quality, supervision, and governance requirements, and only selected audit firms are authorised to perform this type of work.

The firm’s audit registrations are not limited to the UK. Acumon also holds audit licences in several international financial centres, including the Cayman Islands, British Virgin Islands (BVI), Jersey, and Isle of Man. This allows the firm to assist groups with entities spread across more than one jurisdiction.

Many international groups include a mix of UK operating companies, offshore holding entities, investment vehicles, and regulated structures. In sectors such as investment management, technology, energy, and international trade, this can make audit coordination more complex. Work of this kind often requires an understanding of group reporting, consolidation, cross-border structures, and the practical controls behind financial and regulatory records.

Acumon works with finance teams and boards on statutory audit matters while also helping organisations improve the processes that support reporting, governance, and internal control as the business develops.

Audit Capabilities

Acumon carries out audit, assurance, and due diligence work for organisations with different structures, ownership models, and regulatory profiles.

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

Audit engagements are usually managed with close involvement from senior audit professionals throughout the process, from planning and risk assessment through to completion and reporting.

Regulatory Licences and Registrations

Acumon has a number of audit licences and registrations that allow it to support clients with UK and international audit needs.

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

Because of these registrations, the firm can work with groups that include UK entities as well as companies based in major offshore and international financial centres.

Core Services

Alongside statutory external audit, Acumon provides services that help organisations with financial reporting, governance, regulatory assurance, and control review.

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

Audit work is often accompanied by practical discussions with management teams and boards about reporting processes, governance frameworks, risk areas, and the strength of internal controls.

Many businesses first need a statutory audit when they grow beyond the exemption thresholds set under the Companies Act. Others may require more formal assurance because they are preparing for investment, expanding internationally, becoming part of a group, or operating in a regulated environment.

Acumon works with businesses that are:

• approaching their first statutory audit
• preparing for external investment
• expanding into international markets
• operating within corporate group structures

Involving an audit firm early can make it easier to prepare the right records, strengthen reporting processes, and identify gaps in documentation before the audit or assurance work begins.

Contact Information

• Website: acumon.com
• Phone: 020 8567 3451
• E-mail: mail@acumon.com
• Address: 1-2 Craven Road, Ealing, London, W5 2UA, UK

Reflex Accounting

Reflex Accounting operates as a multi-disciplinary accountancy practice based in Birmingham, handling statutory, voluntary, and regulatory audits for organisations across the UK. Their approach focuses on breaking down the auditing process into a structured, risk-based framework, aiming to provide clear practical insights into an organization’s internal controls and financial systems alongside basic compliance. The audit team includes professionals with background experience from larger accounting networks, meaning they bring structured reporting standards to a wider variety of smaller and mid-sized corporate structures.

Reflex Accounting works directly with management teams to explain report findings after fieldwork concludes, focusing on identifying underlying operational risks and helping entities adapt to changing UK accounting frameworks. For businesses operating under financial or legal supervision, they manage specialized assurance reviews to satisfy specific regulatory criteria. The firm supports several distinct organizational types, ranging from owner-managed limited companies to group structures and non-profit organizations.

Key Highlights

• Risk-based audit planning that concentrates efforts on higher-risk operational and financial areas.
• Audit team featuring professionals with background experience from Big 4 and Top 6 accounting practices.
• Direct involvement of senior team members throughout the fieldwork and reporting stages.
• Provision of an audit findings report accompanied by a post-audit review meeting to explain results.
• Registered and regulated external auditors under the Association of Chartered Certified Accountants (ACCA).

Services

• Statutory and voluntary corporate audits
• SRA audit and compliance for law firms
• FCA and CASS compliance audits
• Charity and non-profit audits
• Pension scheme audits
• Bookkeeping, payroll, and tax advisory

Contact Information

• Website: reflexaccounting.co.uk
• Email: info@reflexaccounting.co.uk
• Address: 17 School Rd, Hall Green, Birmingham, B28 8JG
• Phone: +44 121 262 1528
• Instagram: www.instagram.com/reflexaccounting
• Facebook: www.facebook.com/people/Reflex-Accounting/61555478327463

Ark & Co Ltd

Ark & Co Ltd provides independent corporate audit and regulatory reporting services to businesses navigating UK audit thresholds and supervisory requirements. Operating from their base in the West Midlands, they focus on delivering seamless statutory reviews designed to cause minimal disruption to daily business operations. They position their work as an objective check of financial records that can serve external stakeholders, including banks, suppliers, customers, and investors who require audited accounts.

Ark & Co Ltd utilizes modern auditing techniques to deliver meaningful reports while actively looking for operational areas where internal improvements can be made. Beyond standard statutory corporate audits, they specialize in preparing independent regulatory reports tailored for specific oversight bodies. Their work primarily assists businesses that either face legal audit requirements or voluntarily choose to undergo independent reviews to verify the health of their accounting systems.

Key Highlights

• Focus on minimizing business disruption through the use of modern auditing techniques.
• Tailored approach for companies navigating changing UK statutory audit exemption thresholds.
• Provision of independent audit reports recognized by banks, investors, and supervisory bodies.
• Integration of operational reviews to identify efficiency improvements during the auditing process.
• Long-established local presence handling both regional and national regulatory frameworks.

Services

• Statutory company audits
• Regulatory reporting for solicitors and estate agents
• Bookkeeping and accounts preparation
• Business finance and planning
• Payroll services
• Tax compliance, planning, and investigations

Contact Information

• Website: www.arkandco.uk
• Phone: 0121 429 4054
• E-mail: info@arkandco.uk
• Address: The Maltings, 2 Anderson Road, Birmingham, West Midlands B66 4AR
• LinkedIn: www.linkedin.com/company/ark-and-co-ltd-chartered-accountants-and-chartered-tax-advisers
• Instagram: www.instagram.com/ark_and_co_ltd

Grant Thornton

Grant Thornton operates as a large professional services firm combining global network scalability with local market insight through their prominent Birmingham presence. They deliver comprehensive statutory audits, financial advisory, and risk management services to complex organizations, mid-market businesses, and public sector bodies. Their structure allows them to manage large-scale assurance projects, keeping pace with frequent changes in financial regulations and governance requirements across diverse industry sectors.

Grant Thornton deploys multidisciplinary teams that focus heavily on tracking the evolving regulatory landscape, regularly producing insights into financial services rules, cyber security requirements, and governance standards. They support businesses through complex structural transitions, regulatory shifts, and international operations by deploying specialists from their extensive national and global network. The firm balances technical compliance with strategic risk oversight, helping executive teams and boards manage reporting duties effectively.

Key Highlights

• Large scale professional services network combining international reach with regional office insights.
• Dedicated specialists focusing on continuous tracking of financial regulations and initiative grids.
• Multidisciplinary capability covering cyber security integration, ESG tracking, and public sector reorganization.
• Substantial UK resource base including over 5,000 employees and 200 partners across 23 offices.
• Structured assurance methodologies tailored for complex corporate structures and international markets.

Services

• Audit and assurance services
• Financial services advisory
• Consulting and cyber security
• Corporate deals and restructuring
• Forensic and fraud investigations
• Global asset recovery and insolvency
• Domestic and international tax services

Contact Information

• Website: www.grantthornton.co.uk
• Phone: +44 (0)121 212 4000                                                                                   
• Address: 17th Floor, 103 Colmore Row, Birmingham B3 3AG
• LinkedIn: www.linkedin.com/company/grant-thornton-uk
• Instagram: www.instagram.com/gt_trainees

Millet Audit Ltd

Millet Audit Ltd operates as an accountancy firm that provides specialist client asset reviews to regulated businesses across Birmingham. Their work focuses on helping firms meet their regulatory obligations under the Financial Conduct Authority (FCA) Client Assets Sourcebook framework. Using a fully remote delivery model, the team reviews financial controls, segregation procedures, and internal records to verify that client money and safe custody assets are handled correctly.

Millet Audit Ltd aims to look beyond basic checklist compliance by using the audit process to uncover operational vulnerabilities and improve overall governance. They focus on providing straightforward communication and practical feedback to help local investment managers, financial firms, and wealth managers understand their compliance responsibilities. The firm relies entirely on digital communication tools and secure online document systems to carry out their fieldwork without causing disruption to daily business operations.

Key Highlights

• Fully remote audit delivery model using secure online systems to eliminate on-site disruption.
• Focus on identifying operational weaknesses in client asset handling to reduce regulatory risk.
• Tailored approach that reflects the specific operational complexity of each financial firm.
• Direct access to experienced auditors with clear, straightforward feedback throughout the review.
• Registered and regulated by the Institute of Chartered Accountants in England and Wales (ICAEW).

Services

• Independent CASS compliance audits
• Financial and statutory audits
• Client money segregation and reconciliation reviews
• Independent examinations
• Financial assurance services
• Internal control and governance reporting

Contact Information

• Website: milletaudit.com
• Email: info@milletaudit.com
• Phone: +44 (0) 203 084 4550
• Address: Aldgate Tower, 2 Leman Street, London, E1 8FA

Conclusion

At the end of the day, picking a CASS 6 audit firm in Birmingham comes down to finding a realistic balance between strict regulatory rigor and a working style that actually fits your day-to-day operations. No financial business wants to get caught on the wrong side of an FCA review, but nobody wants an audit team that turns their business upside down or bogs them down in endless, clunky communication either. When organizations sit down to choose a provider, they usually look beyond the basic credentials to see how a firm handles the practical stuff – like whether they understand the specific nuances of your investment or wealth management setup, and how clearly they explain necessary process improvements.

That is exactly why we put this guide together. Instead of just listing corporate names or repeating generic marketing fluff, we wanted to lay out the distinct operational approaches available to Birmingham firms. Whether your business thrives on a fully digital, remote audit setup, needs the global backing of a massive professional network, or prefers a localized team with a broad compliance background, the right fit depends entirely on your internal resources. Hopefully, seeing these options side by side gives you a practical starting point to find a partner who keeps your safe custody compliance watertight without making the process painful.