Leading Internal Audit Services Companies in Edinburgh in 2026

Edinburgh has no shortage of firms offering internal audit support, from global consultancies with large local offices to smaller specialists that work closely with charities, financial institutions, and growing private businesses. If you’re comparing providers, it can be difficult to know where to start -many firms offer similar services on paper, yet differ in sector experience, team size, and approach.

Below is a curated overview of internal audit services companies operating in Edinburgh. Rather than explaining how internal audits work, this list is intended to give you a grounded sense of the organisations active in the local market – who they typically serve, how they’re positioned, and why they tend to appear on shortlists. Whether you need ongoing assurance, independent oversight, or extra capacity during a busy period, these firms represent a cross-section of the options available in the city.

1. Acumon

Acumon is a UK-based firm of chartered accountants and advisors providing internal audit as part of our risk and assurance work, including support for organisations in Edinburgh. We approach internal audit as a practical exercise rather than a box-ticking one, looking at governance, controls, and operational risks in a way that fits how a business actually runs. Our team works across different sectors, from corporate groups to charities and subsidiaries of international organisations, so the work often varies depending on structure and regulatory expectations.

As a registered audit firm, we also draw on experience from external audit, tax, and advisory assignments, which tends to shape how we review processes and reporting. Most of our staff are UK-based, and many come from backgrounds in accounting, compliance, or public sector work, so the focus usually stays on UK regulations and real-world implementation rather than theory. Internal audit engagements are often requested by finance leaders who want an independent view of controls, risk management, or technology-related processes.

Key Highlights:

• UK-based chartered accountants and advisory firm
• Provides internal audit within broader risk and assurance services
• Experience with companies, charities, and international subsidiaries
• Registered audit firm authorised by the ICAEW
• Team includes professionals with HMRC and regulatory backgrounds
• Works with organisations across the UK, including Edinburgh

Services:

• Internal audit and assurance reviews
• Risk management and governance support
• IT risk and cybersecurity assessments
• External audit
• Accounts preparation and bookkeeping
• Tax planning and compliance
• Business advisory and due diligence
• Payroll management
• Company secretarial support
• Estate and probate administration

Contact Information:

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

2. Grant Thornton

Grant Thornton provides internal audit services to organisations across the country, including companies and public bodies in Edinburgh. Their work focuses on giving independent assurance and practical feedback on how controls, governance, and risk management are operating in real conditions. Internal audit can be delivered in different ways depending on what a client needs, whether that is a fully outsourced function, extra capacity for an in-house team, or support for specific projects.

They draw on a large pool of risk specialists and subject matter experts, which allows them to look at emerging risks as well as routine processes. The firm also carries out external quality assessments of internal audit functions and can step in temporarily at senior or operational levels if teams are short on resources. Much of their work involves collaboration with management and audit committees, particularly where regulatory expectations or organisational complexity are high.

Key Highlights:

• UK member firm of a global professional network
• Provides outsourced, co-sourced, and staff augmentation internal audit
• Experience with complex organisations and regulated sectors
• Offers external quality assessments of internal audit functions
• Access to specialists across risk, governance, and operations
• Supports organisations across the UK, including Edinburgh

Services:

• Internal audit programmes
• External quality assessments
• Risk and control reviews
• Governance and compliance assurance
• Emerging risk assessments
• Interim audit staff support
• Advisory on audit effectiveness

Contact Information:

• Website: www.grantthornton.co.uk
• LinkedIn: www.linkedin.com/company/grant-thornton-uk
• Instagram: www.instagram.com/gt_trainees
• Address: 7 Castle Street, Edinburgh, EH2 3AH
• Phone: +44 (0)131 229 9181

3. Forvis Mazars

Forvis Mazars delivers internal audit and governance support to organisations in Edinburgh through its UK network of offices. Their approach centres on helping businesses maintain oversight of risk, compliance, and operational controls while adapting to regulatory changes and new business pressures. Internal audit is often positioned as a tool for understanding how well an organisation is functioning, not just whether rules are being followed.

Their teams bring together specialists from different industries, which allows them to address sector-specific risks alongside broader governance issues. They also advise organisations that are setting up a new internal audit function or refining an existing one, working with boards and senior management to align audit activity with business priorities. The work commonly touches on areas such as regulatory change, technology risk, and management responsibilities.

Key Highlights:

• International audit and advisory network with UK presence
• Supports organisations across private and public sectors
• Provides both new internal audit setup and enhancement of existing teams
• Sector-focused expertise across multiple industries
• Works with boards and senior leadership on governance matters
• Active in the Edinburgh professional services market

Services:

• Internal audit planning and delivery
• Risk management advisory
• Governance reviews
• Compliance assessments
• Regulatory change support
• Technology and innovation risk advice
• Board and senior management guidance

Contact Information:

• Website: www.forvismazars.com
• Facebook: www.facebook.com/ForvisMazarsGroup
• Twitter: x.com/ForvisMazarsUK
• LinkedIn: www.linkedin.com/company/forvis-mazars-in-the-uk
• Instagram: www.instagram.com/forvismazarsuk
• Address: Capital Square, 58 Morrison Street, Edinburgh, EH3 8BP, United Kingdom
• Phone: 44 13 13 13 79 00

4. S&W

S&W provides audit and assurance services that can include internal reviews of systems, reporting structures, and financial processes for organisations operating in Edinburgh. Their work often goes beyond statutory requirements, examining how well internal processes support decision-making and how prepared a business is for future challenges. This type of assurance can be useful for leadership teams that want a clearer view of operational risks and financial controls.

Their teams typically work closely with management, spending time understanding how the organisation operates before carrying out testing or analysis. Communication is treated as a key part of the process, with findings discussed as they emerge rather than only at the end. Alongside broader assurance work, they also handle specialist audits such as pensions or royalty arrangements, depending on the nature of the organisation.

Key Highlights:

• UK audit and assurance firm serving a range of businesses
• Focus on systems, reporting structures, and operational readiness
• Involvement of senior staff throughout engagements
• Experience with specialised audit areas such as pensions
• Emphasis on planning and risk identification
• Works with organisations in Edinburgh and across the UK

Services:

• Internal assurance reviews
• Statutory audits
• Financial reporting support
• Non-statutory assurance
• Royalty audits
• Pensions audits
• Corporate reporting analysis

Contact Information:

• Website: www.swgroup.com
• Twitter: x.com/S_W_Group
• LinkedIn: www.linkedin.com/company/swgroupuk
• Address: Q Court, 3 Quality Street, Edinburgh EH4 5BP
• Phone: 44 131 625 5151

5.  Azets

Azets provides internal audit and assurance services to businesses and public sector organisations in Edinburgh through its local offices backed by a wider national network. Their internal audit work looks at financial controls, operational risks, and governance arrangements, with the aim of giving stakeholders a clearer picture of how reliable current processes are. The firm works across multiple industries, so the scope often reflects sector-specific risks as well as general compliance requirements.

Engagements are usually coordinated through a local contact who understands the regional business environment while drawing on expertise from the broader organisation. In addition to internal audit, they carry out external audits and statutory accounting work, which can inform how they assess financial reporting and internal controls. The emphasis is on providing independent insight that helps organisations make informed decisions without disrupting day-to-day operations.

Key Highlights:

• UK and international accounting and advisory group
• Local presence in Edinburgh with national support network
• Works with private, public, and mid-market organisations
• Sector-based experience across multiple industries
• Combines internal audit with broader assurance services
• Provides independent insight into risks and processes

Services:

• Internal audit reviews
• External audit
• Statutory accounting
• Risk and control assessments
• Financial assurance
• Process improvement recommendations
• Governance support

Contact Information:

• Website: www.azets.com
• LinkedIn: www.linkedin.com/company/azets
• Instagram: www.instagram.com/azets_uk
• Address: Quay 2, 139 Fountainbridge, EH3 9QG
• Phone: 0131 473 3500

6. BDO

BDO provides internal audit services as part of its broader risk advisory offering, supporting organisations in Edinburgh facing complex operational and regulatory risks. Their work focuses on evaluating internal controls, governance frameworks, and risk management processes so that boards and audit committees have a clearer understanding of potential vulnerabilities. Internal audit is often integrated with wider enterprise risk management efforts.

Their teams also advise on designing or improving risk frameworks, including areas such as compliance, technology risk, and third-party oversight. In practice, this means working with organisations that are responding to external pressures like digital change, economic uncertainty, or regulatory developments. Internal audit engagements frequently involve ongoing support rather than one-off reviews, particularly where risk environments are evolving.

Key Highlights:

• UK member firm of a global professional services network
• Internal audit delivered through risk advisory teams
• Focus on governance, controls, and enterprise risk
• Supports boards and audit committees
• Experience with technology and third-party risk
• Active across major UK cities including Edinburgh

Services:

• Internal audit programmes
• Enterprise risk management advisory
• Controls assurance
• Corporate governance reviews
• SOX compliance support
• Ethics and compliance assessments
• Technology risk advisory

Contact Information:

• Website: www.bdo.co.uk
• LinkedIn: www.linkedin.com/company/bdo-llp
• Instagram: www.instagram.com/bdo_uk
• Address: 30 Semple street, Edinburgh, EH3 8BL, United Kingdom
• Phone: 0131 347 0347

7. MHA

MHA provides governance, risk, and internal control support to organisations across the UK, including businesses and public bodies in Edinburgh. Their internal audit specialists focus on helping leadership teams understand how risk is managed across the organisation and whether governance arrangements are working as intended. This type of work often sits alongside external audit and financial reporting services, giving a broader view of how controls operate in practice.

As the UK member of the Baker Tilly International network, they can also draw on global expertise when organisations operate across borders or face complex regulatory environments. Internal audit engagements typically involve reviewing compliance processes, testing controls, and reporting findings to management or governing bodies. The aim is to support informed decision making while maintaining independence from day-to-day operations.

Key Highlights:

• UK member firm of an international accounting network
• Provides governance, risk, and control assurance
• Works with both private and public sector organisations
• Combines internal audit with broader assurance services
• Access to international expertise when required
• Supports organisations across the UK, including Edinburgh

Services:

• Internal audit reviews
• Governance assessments
• Risk management support
• Compliance evaluations
• External audit
• Financial reporting advisory

Contact Information:

• Website: www.mha.co.uk
• Email: webenquiries@mha.co.uk
• Facebook: www.facebook.com/100063452388108
• LinkedIn: www.linkedin.com/company/mha-uk
• Instagram: www.instagram.com/mhaaccountants
• Address: 6 St Colme Street, Edinburgh, EH3 6AD
• Phone: +44 (0)131 225 4681

8.  AAB

AAB delivers internal audit services to a wide range of organisations, including businesses, charities, and public sector bodies in Edinburgh. Their approach is risk focused, with audits designed to identify issues early and provide a clear picture of how governance and controls are functioning. They may work alongside in-house teams or take responsibility for the full audit function, depending on the structure of the organisation.

The firm also undertakes targeted projects where specific risks need attention, such as contract reviews or fraud investigations. Internal audit work is often linked with broader assurance activities, including joint venture audits or project support. In situations where organisations need additional capacity, they can provide secondments or specialist staff to integrate temporarily with existing teams.

Key Highlights:

• UK and international audit and advisory firm
• Supports private, public, and not-for-profit sectors
• Offers co-sourced and outsourced internal audit
• Experience with joint ventures and complex contracts
• Provides anti-fraud and investigation support
• Active across Scotland, including Edinburgh

Services:

• Internal audit programmes
• Risk management reviews
• Contract and vendor audits
• Fraud investigation and prevention
• Joint venture audits
• Secondments and project support
• External audit

Contact Information:

• Website: aab.uk
• Facebook: www.facebook.com/AABLLP
• Twitter: x.com/AABGroup_
• LinkedIn: www.linkedin.com/company/aab-accountants
• Instagram: www.instagram.com/_aabgroup
• Address: 81 George St, Edinburgh, EH2 3ES
• Phone: +44 (0)131 357 6666

9. Henderson Loggie

Henderson Loggie provides internal audit services from offices across Scotland, including a base in Edinburgh. Their teams work with organisations in the public, private, and third sectors, offering independent assurance on risk management, governance, and operational controls. Internal audit engagements can be delivered as a fully outsourced function or as support to existing in-house teams.

They also provide consultancy aimed at improving processes, resilience, and compliance with sector standards. The work often extends into areas such as information governance, fraud prevention, and third-party assurance, reflecting the range of risks organisations face today. Their involvement with public sector frameworks means a significant portion of work relates to education bodies, local authorities, and housing organisations.

Key Highlights:

• Scottish accountancy and advisory firm with Edinburgh office
• Works across public, private, and third sectors
• Offers outsourced and co-sourced internal audit
• Experience with public sector assurance frameworks
• Provides governance and risk consultancy
• Member of an international association of accounting firms

Services:

• Internal audit programmes
• Enterprise risk management consulting
• Compliance and control reviews
• Digital and information governance assurance
• Fraud prevention and investigation
• Third-party assurance reporting
• Process improvement consulting

Contact Information:

• Website: hlca.co.uk
• Email: info@hlca.co.uk
• Facebook: www.facebook.com/HendersonLoggie
• LinkedIn: www.linkedin.com/company/hendersonloggie
• Instagram: www.instagram.com/hendersonloggie
• Address: The Stamp Office, Level 5, 10-14 Waterloo Place, Edinburgh, EH1 3EG
• Phone: 01382 200055

10. Saffery

Saffery provides internal audit support to organisations across the UK, including those based in Edinburgh, with a particular focus on internal controls reviews. Their work centres on examining how a company’s control environment actually operates in practice – from management information systems to routine financial processes. By testing and documenting these controls, they help organisations understand whether existing safeguards are working as intended and where gaps may exist.

Internal controls reviews are often used as a form of targeted internal audit, especially when boards or senior management want assurance over financial reporting, compliance obligations, or operational risks. The team looks at how risks are identified and managed, and whether controls are designed and implemented effectively. This can be relevant for organisations undergoing change, preparing for external scrutiny, or simply seeking an independent view of their internal governance.

Key Highlights:

• Provides internal audit support through detailed internal controls reviews
• Focus on evaluating real effectiveness of control environments
• Experience with financial, operational, and compliance risks
• Reviews management information and reporting processes
• Part of an international accounting network
• Supports organisations across the UK, including Edinburgh

Services:

• Internal controls reviews as a form of internal audit
• Assessment of financial reporting controls
• Governance and risk evaluations
• Compliance control testing
• Business process reviews
• Risk assurance services
• External audit

Contact Information:

• Website: www.saffery.com
• Email: info@saffery.com
• Linkedin: www.linkedin.com/company/saffery
• Instagram: www.instagram.com/saffery_uk
• Address: Level 4, 9 Haymarket Square, Edinburgh EH3 8RY
• Phone: +44 (0)131 221 2777

11. Quinn Internal Audit

Quinn Internal Audit is a Scottish assurance provider specialising in internal audit work for the housing sector, including organisations operating in and around Edinburgh. Their services focus on governance, compliance, and operational effectiveness within housing associations and related bodies. The work typically examines areas such as asset management, finance, and tenant services.

In addition to routine audits, they also conduct investigations and advisory projects where issues or risks have been identified. Their sector focus means they are familiar with regulatory expectations specific to social housing and public service delivery. Internal audit assignments often lead to action plans developed jointly with management to address findings and strengthen controls.

Key Highlights:

• Scottish firm focused on the housing sector
• Provides internal audit and business assurance
• Experience with governance and compliance reviews
• Covers operational areas such as asset and housing management
• Conducts investigations when issues arise
• Works with housing organisations across Scotland

Services:

• Internal audit reviews
• IT audit
• Governance assessments
• Business assurance
• Investigations
• Training and advisory support
• Compliance evaluations

Contact Information:

• Website: quinninternalaudit.com
• Email: admin@quinn-internal-audit.co.uk
• Address: GF 4 Grosvenor Gardens, EH12 5JU, Edinburgh
• Phone: 0330 043 3094

12. Johnston Smillie

Johnston Smillie offers internal audit services from its Edinburgh office, supporting organisations across Scotland that require statutory assurance. Their work is governed by professional standards set by the Institute of Chartered Accountants of Scotland and UK audit regulations. While the focus is on external audit of financial statements, the process also involves reviewing internal systems and controls.

For many organisations, the audit becomes an opportunity to analyse how processes operate and where improvements could be made. The firm can conduct work on site or remotely, depending on the client’s setup, and engagements tend to become more streamlined over time as systems are established. This approach is particularly relevant for businesses undergoing their first independent audit or adapting to new reporting requirements.

Key Highlights:

• Edinburgh-based chartered accountancy firm
• Registered statutory auditors in the UK
• Member of the Institute of Chartered Accountants of Scotland
• Provides audit services across Scotland
• Reviews internal systems as part of audit work
• Works with organisations new to independent audit

Services:

• Statutory financial audit
• Review of internal processes and controls
• Analysis of financial systems
• Accountancy support
• Business advisory
• Personal services
• Compliance assistance

Contact Information:

• Website: www.jsca.co.uk
• Email: mail@jsca.co.uk
• Facebook: www.facebook.com/johnstonsmillie
• Twitter: x.com/johnstonsmillie
• LinkedIn: www.linkedin.com/company/johnston-smillie-ltd
• Address: 5 South Gyle Crescent Lane, Edinburgh, EH12 9EG
• Phone: 0131 317 7377

Conclusion

Edinburgh’s internal audit landscape is broader than it might seem at first glance. Alongside the well known international networks, there are mid sized firms, sector specialists, and smaller local practices that focus on particular types of organisations. That mix means there is no single “typical” provider – some teams are geared toward large, complex structures, while others work closely with charities, housing bodies, or owner managed businesses that simply need an independent view of their controls.

In practice, choosing between them usually comes down to fit. Things like sector experience, communication style, and how hands on the team will be often matter more than brand recognition. Many organisations also look for a firm that can adapt as circumstances change, whether that means stepping in temporarily, supporting an existing internal function, or carrying out targeted reviews. The companies listed above reflect the range of options available locally, giving a starting point for comparing who might be the right match for your situation rather than a definitive ranking.