This practical guide provides an overview of internal audit co-sourcing services companies in Birmingham, covering their expertise, service areas, and the types of organisations they support. The article offers a selection of companies rather than ranking them, with the aim of giving readers a clearer view of the options available in this market. The companies range from larger organisations with broad audit and advisory capabilities to more focused specialists working in specific areas of assurance and risk. This overview helps readers understand who these companies are, what they offer, and which factors may matter when choosing an internal audit co-sourcing partner.
Acumon
Acumon provides internal audit co-sourcing services for organisations seeking additional assurance support, specialist expertise, and flexible internal audit resources. The firm works with businesses, charities, and other organisations that need independent reviews of governance arrangements, risk management processes, and internal controls.
Its internal audit approach is based on structured risk assessment and tailored review programmes designed around each organisation’s objectives, operational environment, and regulatory responsibilities. Acumon supports existing internal audit functions by providing additional capacity, specialist knowledge, and independent perspectives on areas requiring further examination.
The firm works with organisations across different sectors, including commercial businesses, not-for-profit entities, and regulated organisations. Internal audit co-sourcing engagements are structured to complement existing teams and provide practical insights into control effectiveness, operational risks, and governance processes.
Acumon supports organisations operating in Birmingham and across the UK with internal audit services that align with recognised professional practices and organisational requirements. Its work focuses on helping management teams and boards maintain effective oversight of risks, controls, and internal processes.
Internal audit co-sourcing can support organisations during periods of growth, organisational change, increased regulatory expectations, or when additional specialist resources are needed. Acumon combines audit experience with risk advisory knowledge to provide support alongside internal teams.
Audit Capabilities
Acumon provides internal audit co-sourcing services across a range of organisational structures and business environments.
These include:
- Internal audit co-sourcing support alongside existing audit teams
- Risk-based internal audit planning and reviews
- Governance and internal control assessments
- Operational process reviews and improvement recommendations
- Compliance and risk management reviews
- Independent assurance support for management and boards
Internal audit engagements are designed around the organisation’s objectives, risk profile, and existing assurance framework. Acumon works with internal stakeholders to provide practical audit findings and recommendations that support stronger governance arrangements.
Regulatory Licences and Registrations
Acumon operates as a professional audit and advisory firm supporting organisations with assurance, governance, and risk-related services.
These include:
- UK audit registration
- Professional audit and accounting qualifications
- Experience supporting regulated organisations
- Internal audit and assurance expertise
- Risk management and governance knowledge
- Compliance-focused advisory experience
These professional credentials and areas of expertise support Acumon’s ability to deliver structured internal audit assignments for organisations requiring independent assurance and additional audit capability.
Core Services
Acumon provides internal audit and assurance services that support organisations in reviewing controls, managing risks, and strengthening governance processes.
These include:
- Internal audit co-sourcing services
- Outsourced internal audit support
- Risk assessment and audit planning
- Internal control reviews
- Governance and compliance reviews
- Operational assurance assessments
- Risk management support
Acumon works with organisations that need additional internal audit resources while maintaining their existing governance structures and management oversight.
Its internal audit co-sourcing services support businesses that are:
- Expanding operations and reviewing internal controls
- Preparing for regulatory or governance changes
- Strengthening risk management frameworks
- Improving internal assurance processes
- Managing complex operational environments
By combining audit expertise with a practical understanding of business processes, Acumon helps organisations evaluate their control environment and identify areas for improvement.
Contact Information
- Website: acumon.com
- Phone: 020 8567 3451
- Email: [email protected]
- Address: 1-2 Craven Road, Ealing, London, W5 2UA, UK
Bishop Fleming
Bishop Fleming provides internal audit and risk assurance services to organisations across the UK, including outsourced and co-sourced internal audit arrangements. The firm supports public and private sector organisations with reviews covering governance, controls, risk management and compliance.
Its internal audit teams work with organisations that need additional audit resources, specialist reviews or support with maintaining effective assurance frameworks.
Key Facts
- Ideal for: Public and private sector organisations requiring assurance support
- Core services: Internal audit co-sourcing, risk assurance, governance reviews
- Specialization: Internal controls and risk management
- Industries: Education, healthcare, housing and commercial organisations
- Location: Birmingham and UK offices
Contact Information
- Website: www.bishopfleming.co.uk
- Phone: 03333 219000
- Address: 55 Colmore Row, Birmingham, B3 2AA
- LinkedIn: www.linkedin.com/company/bishop-fleming-chartered-accountants
- Facebook: www.facebook.com/people/Life-at-Bishop-Fleming/100093464198343
- Twitter: x.com/BishopFlemingUK
- Instagram: www.instagram.com/bishopfleminguk
Kreston Reeves
Kreston Reeves offers internal audit outsourcing and co-sourcing services for organisations reviewing their governance arrangements, risk processes, and control environments. The firm supports businesses, charities, and public sector organisations through planned audit programmes, specialist assignments, and advisory engagements. Its services include internal audit reviews, technology assessments, fraud-related evaluations, and audit committee support, helping organisations strengthen oversight, improve controls, and maintain effective assurance frameworks.
Key Facts
- Ideal for: Organisations requiring flexible internal audit resources
- Core services: Co-sourced internal audit, governance reviews, control assessments
- Specialization: Internal audit advisory and assurance
- Industries: Corporate, not-for-profit and public sector
- Location: UK-wide
Contact Information
- Website: www.krestonreeves.com
- Address: 2nd Floor, 168 Shoreditch High Street, London, E1 6RA
- Phone: +44 (0)330 124 1399
- Twitter: x.com/KrestonReeves
- LinkedIn: www.linkedin.com/company/kreston-reeves
Grant Thornton
Grant Thornton provides internal audit co-sourcing, outsourcing and advisory services for organisations that need additional assurance expertise. Its teams support internal audit functions with risk-based reviews, governance assessments and specialist resources.
The firm works with organisations across multiple sectors, providing support for both ongoing audit programmes and specific assurance projects.
Key Facts
- Ideal for: Organisations needing access to wider audit expertise
- Core services: Internal audit co-sourcing, risk reviews, audit advisory
- Specialization: Governance and internal control assurance
- Industries: Public sector, financial services and commercial organisations
- Location: UK-wide
Contact Information
- Website: www.grantthornton.co.uk
- Email: [email protected]
- 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
BDO
BDO provides internal audit co-sourcing services as part of its wider risk advisory offering, supporting organisations with assurance and governance requirements. The firm’s teams assist with internal controls testing, governance reviews, technology risk assessments, and assurance programmes. BDO works alongside existing audit departments where additional expertise or capacity is needed, helping organisations review risk areas, evaluate controls, and strengthen internal audit processes through structured support.
Key Facts
- Ideal for: Organisations requiring specialist audit support
- Core services: Internal audit co-sourcing, controls reviews, risk assurance
- Specialization: Governance, technology and compliance reviews
- Industries: Commercial, financial services and public sector
- Location: UK-wide
Contact Information
- Website: www.bdo.co.uk
- Phone: 0121 352 6200
- Address: Two Snowhill Birmingham, B4 6GA, United Kingdom
- LinkedIn: www.linkedin.com/company/bdo-llp
- Instagram: www.instagram.com/bdo_uk
Protiviti
Protiviti provides internal audit sourcing services, including co-sourcing and staff augmentation support for organisations that need additional internal audit resources. Its teams combine internal audit methodology with expertise across business processes, technology and operational risks.
The company supports organisations looking to expand internal audit capability without creating additional permanent headcount.
Key Facts
- Ideal for: Businesses needing specialist internal audit resources
- Core services: Internal audit co-sourcing, outsourcing, audit support
- Specialization: Technology and operational risk
- Industries: Financial services, commercial and regulated sectors
- Location: UK operations
Contact Information
- Website: www.protiviti.com
- Phone: +44.12.1616. 4600
- Address: Second Floor, AIR, 35 Homer Road, Solihull B91 3QJ, United Kingdom
- LinkedIn: www.linkedin.com/company/protiviti
- Facebook: www.facebook.com/protiviti
- Twitter: x.com/protiviti
- Instagram: www.instagram.com/protiviti
Forvis Mazars
Forvis Mazars provides internal audit and risk advisory services for organisations seeking independent assurance over governance structures, internal controls, and risk management processes. Its internal audit teams support organisations through planned reviews, advisory assignments, and enhancements to existing assurance functions. The company helps organisations assess control effectiveness, review operational risks, and improve governance arrangements through structured audit support tailored to their specific requirements and business environment.
Key Facts
- Ideal for: Organisations reviewing governance and controls
- Core services: Internal audit co-sourcing, risk advisory, assurance reviews
- Specialization: Governance and compliance
- Industries: Public sector, financial services and commercial organisations
- Location: Birmingham and UK offices
Contact Information
- Website: www.forvismazars.com
- Phone: +44 (0) 121 232 9500
- Address: 3 Chamberlain Square, Birmingham, B3 3AX, United Kingdom
- LinkedIn: www.linkedin.com/company/forvis-mazars-in-the-uk
- Twitter: x.com/ForvisMazarsUK
- Instagram: www.instagram.com/forvismazarsuk
Deloitte
Deloitte provides internal audit co-sourcing and advisory services for organisations requiring support with governance, risk management, and control frameworks. Its internal audit teams assist organisations with assurance programmes, audit transformation initiatives, and specialist reviews where additional expertise is required. The company works with organisations across different sectors, helping them assess internal controls, review risk processes, and strengthen their overall assurance approach through structured audit support.
Key Facts
- Ideal for: Large organisations with complex assurance needs
- Core services: Internal audit co-sourcing, risk advisory, controls reviews
- Specialization: Enterprise risk and governance
- Industries: Multiple sectors
- Location: UK-wide
Contact Information
- Website: www.deloitte.com
- Phone: +44 (0)121 632 6000
- Address: Four Brindleyplace Birmingham, B1 2HZ United Kingdom
- LinkedIn: www.linkedin.com/company/deloitte
- Facebook: www.facebook.com/deloitteuk
- Twitter: x.com/deloitteuk
RSM
RSM provides internal audit services for organisations seeking support with risk management, internal controls, and governance arrangements. Its teams deliver outsourced and co-sourced internal audit solutions tailored to organisational needs, helping businesses review processes and strengthen assurance frameworks. The company works with businesses and public sector organisations that require additional audit capability, specialist expertise, or independent support to evaluate risks, improve controls, and maintain effective governance practices.
Key Facts
- Ideal for: Growing organisations and established audit teams
- Core services: Internal audit co-sourcing, risk reviews, controls testing
- Specialization: Governance and operational assurance
- Industries: Private sector, public sector and regulated industries
- Location: UK-wide
Contact Information
- Website: www.rsmuk.com
- Phone: +44 (0)1782 216130
- Address: 10th Floor, 103 Colmore Row, Birmingham, B3 3AG
- LinkedIn: www.linkedin.com/company/rsm-uk
- Instagram: www.instagram.com/rsm.uk
Crowe
Crowe provides internal audit and risk advisory services, supporting organisations with assurance reviews, governance assessments, and internal control evaluations. Its internal audit teams work with organisations that need additional expertise for specific reviews, ongoing assurance programmes, or improvements to existing audit functions. The company supports clients across different sectors by reviewing risk management processes, assessing control effectiveness, and providing independent insights that help strengthen governance and operational oversight.
Key Facts
- Ideal for: Organisations needing risk and compliance support
- Core services: Internal audit co-sourcing, risk advisory, controls reviews
- Specialization: Governance and regulatory assurance
- Industries: Financial services, charities and commercial organisations
- Location: UK-wide
Contact Information
- Website: www.crowe.com
- Phone: +44 (0)20 7842 7100
- Email: [email protected]
- Address: 55 Ludgate Hill, London, EC4M 7JW
- LinkedIn: www.linkedin.com/company/crowe-uk
- Twitter: x.com/CroweUK
- Instagram: www.instagram.com/crowe_uk
Conclusion
This guide highlights a selection of internal audit co-sourcing services companies serving Birmingham and the wider UK market. Providers vary in their approach, from specialist internal audit support to broader risk advisory and governance services.
The right option depends on factors such as organisation size, sector requirements, existing internal audit resources and the level of specialist expertise needed. A practical comparison of service scope, experience and delivery model can help organisations identify a suitable co-sourcing partner.