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CASS 6 Audit Companies in Edinburgh: Companies and Services Guide

Edinburgh is home to several audit companies that offer CASS 6 audit services. These companies assist FCA-regulated investment businesses with the proper safeguarding of client assets in line with the custody rules.

Agencies in the city carry out reviews of segregation arrangements, reconciliations, record-keeping and controls related to client assets. They provide the independent assurance required for regulatory reports and help firms handle compliance responsibilities.

Many of these companies have experience with custody arrangements across various types and sizes of operations. They work with investment firms to confirm that client assets remain properly identified and kept separate from the company’s own holdings.

Acumon

Acumon is a UK firm of chartered accountants and registered auditors providing CASS audit services to FCA-regulated investment firms that hold client money and assets. The company conducts comprehensive CASS 5, 6 and 7 audits to verify compliance with the FCA Client Assets Sourcebook rules and the relevant sections of the FCA Handbook. Acumon holds regulation from the ICAEW and the FRC, which supports its work in this specialist regulatory area.

Acumon offers a full-service approach that combines CASS audits with statutory audit, accounts, tax, payroll and other advisory services. The company applies a structured process covering planning, systems review, testing, compliance assessment, reporting and follow-up support. It uses efficient methods including a dedicated audit portal and remote working capability to review reconciliations, segregation, record-keeping and controls. Acumon prepares reports for FCA submission that include findings and recommendations. The company also holds a Public Interest Entity (PIE) audit licence and brings experience from auditing accounts and ERP systems across different types of organisations.

CASS Audit Capabilities

Acumon provides external audit services across a wide range of organisational structures and sectors.

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 typically led by senior audit professionals with direct involvement throughout the engagement.

Regulatory Licences and Registrations

Acumon holds several audit registrations that enable it to support organisations operating across multiple jurisdictions.

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 allow the firm to provide audit services to groups that include entities in both the UK and key international financial centres.

Core Services

In addition to statutory external audit, Acumon provides a range of services that support financial reporting and governance.

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 delivered alongside discussions with management and boards regarding financial reporting processes and governance frameworks.

Many organisations initially encounter statutory audit requirements as they grow and exceed the audit exemption thresholds set out in the Companies Act.

Acumon works with businesses that are:

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

Early engagement with an audit firm can help ensure that financial reporting systems and documentation are aligned with statutory audit requirements.

Contact Information:

BDO

BDO operates as an accountancy company with offices in Edinburgh and Glasgow. The company advises a wide range of clients including local owner managed businesses, mid to large sized private and listed groups, individuals, public sector organisations, pension schemes and their trustees and not-for-profit entities across Scotland, the UK and internationally. The company provides expertise in business services and accounting, taxation, audit and assurance, business restructuring, corporate finance and transaction support, and risk advisory services.

BDO focuses on delivering exceptional client service and value. The company works with private individuals, dynamic start-ups, established family businesses, local charities, public sector bodies, expanding international companies or listed groups. 

Key Highlights:

  • Delivers services across Scotland with a presence in Edinburgh and Glasgow
  • Supports clients from various sectors including public sector and not-for-profit
  • Maintains dedicated professional staff in the Scottish offices

Services:

  • Audit and assurance
  • Taxation
  • Business restructuring
  • Corporate finance and transaction support
  • Risk advisory services

Contact Information:

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

Johnston Carmichael

Johnston Carmichael runs as a chartered accountants and business advisers company in Edinburgh. The company offers a range of services tailored to business and personal finance needs. Johnston Carmichael provides tax planning, audit, payroll services, bookkeeping, employment tax and pension and succession planning. The firm works closely to understand specific situations and delivers practical advice that fits different business stages. Johnston Carmichael maintains a strong presence in Scotland as an independent operation and focuses on supporting both personal and corporate financial matters with attention to detail.

Key Highlights:

  • Award winning team of chartered accountants and business advisers
  • Tailors services to individual business needs
  • Serves as the largest independent operation in Scotland
  • Focuses on practical advice for different business stages
  • Supports both personal finance and corporate requirements

Services:

  • Employment tax
  • Pension and succession planning
  • Tax planning
  • Payroll services
  • Bookkeeping

Contact Information:

  • Website: johnstoncarmichael.com
  • Address: 7-11 Melville Street, Edinburgh, EH3 7PE
  • Phone: 0131 220 2203
  • LinkedIn: www.linkedin.com/company/johnston-carmichael-chartered-accountants-and-business-advisers
  • Twitter: x.com/JC_Accountants
  • Facebook: www.facebook.com/JohnstonCarmichael
  • Instagram: www.instagram.com/johnston_carmichael

Deloitte

Deloitte operates from a central Edinburgh office at Haymarket Square, where it supports financial services clients across Scotland. The firm works with banks, asset managers, pension schemes, insurers, and other regulated organisations that need audit, assurance, and regulatory support.

They’ve got solid experience handling complex CASS stuff, and they can draw on all the usual Big Four resources when needed. The team at Haymarket Square does good quality assurance and regulatory work. A lot of it involves going through client asset controls and governance in detail.

They work with organisations of all sizes across Scotland and further afield. Having that office in Edinburgh makes it easy for local firms to get hold of them. Plenty of people pick Deloitte when they want scale, a strong reputation, and real technical know-how.

Key Highlights:

  • Serves financial services clients in banking and asset management
  • Handles pensions and insurance work
  • Maintains a dedicated office in central Edinburgh

Services:

  • Risk, regulatory and forensic
  • Tax
  • Assurance
  • Audit
  • Strategy and transactions

Contact Information:

  • Website: www.deloitte.com
  • Address: 9 Haymarket Square, Edinburgh, EH3 8RY, United Kingdom
  • Phone: +44 (0)131 221 0002
  • E-mail: Globalprandeminence@deloitte.com
  • LinkedIn: www.linkedin.com/company/deloitte
  • Twitter: x.com/deloitte
  • Facebook: www.facebook.com/deloitte
  • Instagram: www.instagram.com/deloitte

Prydis

Prydis delivers specialist CASS audit and assurance services as an accountancy company. The company supports FCA-regulated firms that hold or control client money or custody assets. Prydis offers both reasonable and limited assurance reports depending on regulatory classification. The company includes pre-audit assessments and efficient delivery that can be remote or on-site. Prydis maintains branches including one in Edinburgh alongside others in the South West.

Prydis focuses on compliance with FCA client asset rules for CASS 5, CASS 6, or CASS 7. The company works with investment and wealth management firms, IFAs, fund managers, payment service providers and fintech businesses.

Key Highlights:

  • Offers ongoing support after the audit process
  • Provides reasonable and limited assurance reports
  • Conducts pre-audit assessments with remote or on-site delivery options
  • Supports regulated firms nationwide 
  • Conducts audits for client money and custody assets

Services:

  • Business advisory
  • Mortgage and protection advice
  • Audit and assurance
  • Wealth management
  • Accounts

Contact Information:

  • Website: prydis.com
  • Address: 14-18 Hill St, Edinburgh, Scotland, EH2 3JZ
  • Phone: 01637 872328
  • E-mail: mail@prydis.com
  • LinkedIn: www.linkedin.com/company/prydis

RSM

RSM operates as a company providing audit, tax and consulting services with a presence in Edinburgh. The company delivers a range of professional offerings and works through its regional setup in Scotland. RSM focuses on understanding specific needs in the local market and applies its experience to support businesses in different situations. RSM works in Edinburgh as part of a wider UK network, giving local clients access to both the Scottish team and broader national resources. The firm takes a structured process to audit, tax, and consulting work, focusing on support that fits the way each business operates rather than treating every engagement the same.

They pay attention to how different organisations manage their requirements and adapt their input accordingly. The company combines audit expertise with tax advice and consulting support to address various business matters. It keeps its processes straightforward and aims to deliver consistent service that fits the Scottish market context. RSM continues to develop its offerings while staying connected to broader resources available through the network.

Key Highlights:

  • Provides audit and related professional services
  • Operates with a regional managing partner for Scotland
  • Delivers tax and consulting support alongside audit work

Services:

  • Audit services
  • Tax
  • Consulting
  • Risk and governance
  • Business transformation

Contact Information:

  • Website: www.rsmuk.com
  • Address: 3rd Floor, 2 Semple Street, Edinburgh, EH3 8BL
  • Phone: +44 (0)131 659 8300
  • LinkedIn: www.linkedin.com/company/rsm-uk
  • Instagram: www.instagram.com/rsm.uk

Grant Thornton

Grant Thornton maintains an office in Edinburgh and connects businesses to audit, tax and advisory services. The company draws on its network to address various challenges that companies face in the Scottish capital. Grant Thornton advises with expertise tailored to local conditions while linking to broader resources for ongoing needs. The company sits at a central spot in the city and works with businesses aiming for success and growth.

Grant Thornton offers audit and assurance along with deals support. The company provides forensic and investigation services in addition to insolvency options and tax advice. Grant Thornton also handles government and public sector matters plus restructuring where required. The company focuses on practical assistance for different business goals in the area.

Key Highlights:

  • Covers a mix of audit tax and advisory work
  • Serves businesses in the Scottish capital
  • Connects to national and international networks for support
  • Operates from a central Edinburgh location

Services:

  • Restructuring
  • Government and public sector
  • Tax
  • Forensic and investigation services
  • Deals

Contact Information:

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

Saffery

Saffery works as accountants, auditors and tax advisors with a focus on Edinburgh. The company handles accounting audit and assurance tax transaction services and business advisory across personal and business affairs. Saffery supports wealth generation preservation and succession for its clients. The company advises on areas that include owner managed businesses, private wealth and family trusts along with agricultural and rural businesses entrepreneurs hospitality real estate recruitment professional practices international businesses and charities.

Saffery operates as a member of Nexia. The company provides services that fit individual client situations in Scotland and combines accounting expertise with advisory input. It maintains attention to detail across different types of work and adapts its approach to match specific requirements. Saffery delivers practical support for both personal and business financial matters.

Key Highlights:

  • Covers multiple sectors including agricultural real estate and international businesses
  • Supports wealth generation preservation and succession planning
  • Focuses on private clients charities and owner managed businesses
  • Delivers tailored advice for business and personal needs
  • Operates as a member of Nexia

Services:

  • Tax and VAT advice
  • Business advisory
  • Transaction services
  • Audit and accounting

Contact Information:

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

Forvis Mazars

Forvis Mazars runs an office in Edinburgh and specialises in audit, tax and advisory services. The company supports sectors such as financial services, public and social sector, hospitality, energy and infrastructure. Forvis Mazars works with clients in insurance, banking, retail and other areas. The company applies a hybrid working model and maintains a practical approach when delivering its services. It pays close attention to understanding requirements in Scotland and adapts its input to suit different situations.

Forvis Mazars delivers accounting and outsourcing, audit and assurance, consulting, financial advisory and tax services. The company also handles sustainability matters, private client services and international business support. It combines various service areas to address a range of business needs. Forvis Mazars keeps its engagements straightforward while focusing on the specific context of each organisation.

Key Highlights:

  • Handles sustainability and private client matters
  • Offers international business services alongside core audit and tax work
  • Serves financial services and public sector clients
  • Provides a range of advisory and compliance services
  • Delivers accounting and outsourcing support

Services:

  • Sustainability
  • Accounting and outsourcing
  • Tax
  • Consulting
  • Financial advisory

Contact Information:

  • Website: www.forvismazars.com
  • Address: Capital Square, 58 Morrison Street, Edinburgh, EH3 8BP, United Kingdom
  • Phone: +44 131 313 7900
  • LinkedIn: www.linkedin.com/company/forvis-mazars-in-the-uk
  • Twitter: x.com/ForvisMazarsUK
  • Facebook: www.facebook.com/ForvisMazarsGroup
  • Instagram: www.instagram.com/ForvisMazarsGroup

KPMG

KPMG maintains an office in Edinburgh and delivers professional services to the corporate market and public sector. The company supports audit tax and advisory work across various sectors in Scotland. KPMG assists with risk management performance improvement and business goals. The company operates from Saltire Court in the city.

KPMG provides independent external audit services along with internal audit support. The company covers corporate tax, personal taxes, indirect tax and international taxes. KPMG offers strategy risk management technology forensics and transformation advisory. The company also handles specialised areas such as cybersecurity data analytics and ESG.

Key Highlights:

  • Provides independent external and internal audit support
  • Covers a broad range of tax services including international matters
  • Delivers core audit tax and advisory services
  • Offers specialised advisory in risk management and transformation

Services:

  • Technology and cybersecurity
  • Tax
  • Advisory
  • Audit
  • ESG

Contact Information:

  • Website: kpmg.com
  • Address: Saltire Court, 20 Castle Terrace, Edinburgh, EH1 2EG
  • Phone: +44 131 222 2000
  • LinkedIn: www.linkedin.com/company/kpmg-uk
  • Twitter: x.com/kpmguk
  • Facebook: www.facebook.com/KPMG

EY

EY operates in the United Kingdom with a focus on assurance consulting strategy and transactions along with tax services. The company works with through integrated service lines and sector knowledge to address opportunities and manage risks. EY uses data AI and advanced technology in its work. The company helps with regulatory requirements and stakeholder needs from its presence in the UK market.

EY delivers audit services as part of its assurance offerings. The company provides insights on financial reporting, climate change and sustainability matters. EY maintains operations that cover a range of industries while supporting businesses in the Edinburgh area through its national setup. The company engages in various professional activities that align with current business challenges.

Key Highlights:

  • Supports work in financial reporting and sustainability
  • Engages with sector specific knowledge
  • Maintains operations across the United Kingdom
  • Covers multiple service lines including assurance and tax

Services:

  • Sustainability
  • Technology
  • Tax
  • Consulting
  • Strategy consulting

Contact Information:

  • Website: www.ey.com
  • Address: Atria One, 144 Morrison Street, Edinburgh EH3 8EX
  • Phone: +44 113 298 2200
  • LinkedIn: www.linkedin.com/company/ernstandyoung
  • Twitter: x.com/EYnews
  • Facebook: www.facebook.com/EY

AAB

AAB provides professional services from its office in Edinburgh. The company specialises in accounting audit tax corporate finance payroll people consultancy wealth management and business advisory. AAB delivers solutions that combine local expertise with broader knowledge. The company works with businesses and individuals throughout Scotland and internationally from its location at George Street.

AAB serves with audit and assurance business advisory and corporate finance services. The company also covers hotel accounting, payroll and employment matters along with people consultancy and private client work. AAB handles restructuring, recovery, sustainable business and ESG issues in addition to tax and virtual finance. The company operates as part of an alliance within a global accounting network.

Key Highlights:

  • Focuses on practical solutions for business needs
  • Offers a full range of accountancy and advisory services
  • Supports various sectors in Scotland

Services:

  • People consultancy
  • Corporate finance
  • Business advisory
  • Payroll and employment
  • Sustainable business and ESG

Contact Information:

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

PwC

PwC maintains an office in Edinburgh and delivers a range of professional services. The company covers audit and assurance tax and cyber security among other areas. PwC supports public and private sector organisations in Scotland from its base in Morrison Street. The company works with local talent and engages in community partnerships.

PwC focuses on audit consulting deals risk and tax services. The company handles work across industries and provides support for business goals and risk management. PwC operates from Atria One in the city. The company maintains a presence in Scotland’s capital with specialists available locally.

Key Highlights:

  • Supports public and private sector work 
  • Delivers services in the local market
  • Engages with local community initiatives
  • Covers audit consulting deals risk and tax areas

Services:

  • Deals
  • Risk
  • Tax
  • Consulting
  • Cyber security

Contact Information:

  • Website: www.pwc.co.uk
  • Address: Atria One, 144 Morrison Street, Edinburgh, EH3 8EX
  • Phone: +44 (0)131 226 4488
  • LinkedIn: www.linkedin.com/company/pwc-uk
  • Facebook: www.facebook.com/PwCUK
  • Instagram: www.instagram.com/pwc_uk

Conclusion

Picking the right firm for your CASS 6 audit in Edinburgh ultimately comes down to fit. Some companies bring the weight of a big network and extensive resources, while others feel more approachable and genuinely tuned in to the day-to-day realities of regulated investment businesses.

Whichever route you go, the firms listed here all have solid experience with client asset rules and the level of scrutiny the FCA demands. That said, don’t rely on websites or brochures alone. Have proper conversations with two or three of them. See how they explain things, whether they actually understand your setup, and if their working style clicks with yours.

A good CASS 6 audit shouldn’t just tick the regulatory box — it should also give you practical insights and confidence that your client assets are properly protected.