IR35 Services Companies in the UK: A Guide to Specialist Providers and Support
AC
Acumon Chartered Accountants·14 min read
IR35 has become an important consideration for businesses engaging contractors and for professionals working through personal service companies. As the rules have evolved, organisations have needed to take a more structured approach to assessing employment status, managing compliance and reducing the risk of unexpected tax liabilities.
The UK market includes a wide range of firms offering IR35 services, from specialist tax consultancies and employment status experts to full-service accountancy and advisory practices. While their approaches and areas of expertise vary, many support clients with status assessments, compliance processes, contract reviews and ongoing advisory services tailored to changing regulatory requirements.
This guide highlights a selection of companies providing IR35 services across the UK. Rather than ranking providers, the aim is to offer practical context on the organisations operating in this space, the services they typically provide and the types of clients they support.
Acumon
Acumon is a UK firm of chartered accountants and advisors providing IR35 services to businesses and contractors across the UK.
The firm works with organisations ranging from owner-managed businesses and growing companies through to corporate groups, recruitment businesses and regulated organisations. IR35 services are designed to help organisations understand their tax obligations, support compliance and manage employment status considerations.
Acumon provides IR35 services as part of its wider tax and advisory offering. Engagements are tailored to each organisation's operating model, contractual arrangements and compliance requirements, helping businesses navigate the UK's off-payroll working rules and associated tax obligations.
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. These licences enable the firm to support organisations operating across multiple jurisdictions.
The IR35 rules form an important part of the UK's employment tax framework and may apply where individuals provide services through intermediary companies. Professional advice can help organisations understand their responsibilities, support compliance and manage tax reporting requirements as legislation continues to evolve.
Acumon works with business owners, directors, finance teams and management to support IR35 compliance while helping organisations strengthen governance arrangements, tax processes and financial reporting.
IR35 Capabilities
Acumon provides IR35 services across a wide range of organisational structures and sectors.
These include:
UK companies and corporate groups
owner-managed businesses and growing companies
UK subsidiaries of international groups
regulated organisations
organisations operating across multiple jurisdictions
businesses engaging contractors and consultants
IR35 engagements are typically led by experienced 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 support organisations operating across both the UK and key international financial centres.
Core Services
In addition to IR35 services, Acumon provides a range of services that support tax compliance, financial reporting and business governance.
These include:
tax compliance and employment tax advisory
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
IR35 work is often delivered alongside discussions with management regarding employment tax, contractual arrangements, governance and statutory compliance.
Many organisations seek IR35 support as tax legislation evolves, business operations expand and compliance requirements become increasingly complex.
Acumon works with organisations that are:
expanding business operations
strengthening governance frameworks
managing regulatory obligations
operating across multiple jurisdictions
preparing for future growth
Early engagement can help ensure that tax compliance, governance arrangements and employment status processes remain aligned with legislative requirements and organisational objectives.
Address: 1-2 Craven Road, Ealing, London, W5 2UA, UK
Phone: 020 8567 3451
The Infinity Group
The Infinity Group focuses on IR35 compliance services for contractors, recruitment agencies, consultancies and businesses that engage off-payroll workers. Their approach centres on helping clients understand employment status, review working arrangements and meet HMRC requirements before issues arise. Alongside status assessments, they examine contracts and day-to-day working practices, recognising that both play a role when IR35 status is considered.
Across their IR35 offering, they cover the practical steps involved in ongoing compliance, from preparing Status Determination Statements (SDS) to supporting organisations during HMRC compliance checks. Their services fit alongside payroll and accountancy support, giving businesses access to IR35 guidance as part of wider workforce and compliance management.
Key Highlights
Support for contractors, agencies, consultancies and end clients
IR35 status assessments based on contracts and working practices
Assistance with Status Determination Statements (SDS)
Ongoing contract reviews and compliance checks
HMRC compliance check support
Payroll and accountancy services alongside IR35 compliance
Streets offers accounting and tax support for freelancers, contractors and limited company directors, with IR35 forming part of its contractor services. Their work focuses on helping independent professionals understand how the off-payroll working rules apply to their contracts while managing the tax and accounting responsibilities that come with contracting through a personal service company.
Their contractor support combines IR35 guidance with ongoing financial administration, allowing freelancers to deal with compliance and routine accounting through the same adviser. In addition to reviewing employment status, they assist with company formation, payroll, VAT and tax planning that reflects the way contractors typically operate.
Key Highlights
Support for freelancers, contractors and limited company directors
IR35 guidance linked to contractor accounting
Employment status and contract reviews
Advice for creative professionals and IT consultants
Address: Almondsbury Business Centre, Woodlands, Bradley Stoke, Bristol BS32 4QH, UK
Phone: 0117 332 3640
Grant Thornton
Grant Thornton advises businesses on managing IR35 and the off-payroll working rules, with a particular focus on organisations that engage contractors through personal service companies and other labour supply arrangements. Their approach covers the wider compliance process, including employment status assessments, contractor population reviews and the responsibilities that fall on end users under the legislation.
Their IR35 support extends beyond individual status decisions and looks at the processes businesses use to manage contractor engagements. This includes reviewing labour supply chains, helping organisations establish assessment procedures, preparing Status Determination Statements (SDS), and supporting governance around PAYE obligations and HMRC expectations. International contractor arrangements also form part of their advisory work where UK tax rules may apply.
Key Highlights
IR35 support for businesses engaging contractors
Employment status assessments under the off-payroll rules
Review of labour supply chains and contractor populations
Accounting Wise works with contractors, freelancers and businesses that need support with IR35 compliance alongside their accounting and tax obligations. Their services cover employment status, contract reviews and off-payroll requirements, helping clients understand which rules apply to their engagements and what responsibilities follow.
IR35 support forms part of a wider contractor accounting service, allowing clients to deal with status assessments, payroll obligations and ongoing compliance through the same adviser. They also assist businesses that engage contractors by reviewing working arrangements and helping them manage their obligations under the off-payroll working rules.
Key Highlights
Support for contractors, freelancers and businesses
IR35 compliance as part of contractor accounting services
Address: The Carriages, Station Road, Ware, SG12 9PL UK
Phone: 0330 113 8442
DNS Accountants
DNS Accountants offers IR35 support for freelancers and contractors working through limited companies. Their service focuses on reviewing contracts and working practices to determine whether an engagement falls inside or outside IR35. Alongside the assessment, they explain the outcome and highlight any areas that could affect employment status.
Where changes are needed, they provide practical recommendations to strengthen compliance before a contract begins or is renewed. IR35 reviews sit alongside contractor accounting services, giving clients support with tax, payroll and ongoing financial administration throughout their engagement.
Address: DNS House, 382 Kenton Road, Harrow, Middlesex, HA3 8DP
Phone: 03330602437
BDO
BDO advises organisations that engage contractors on their responsibilities under the off-payroll working rules. Their IR35 services focus on helping businesses identify contractor populations, assess employment status and establish processes that support ongoing compliance with HMRC requirements.
Their work covers the full compliance process, from reviewing labour supply chains and preparing Status Determination Statements (SDS) to assessing PAYE obligations where IR35 applies. They also advise businesses on governance, due diligence and quality assurance, helping organisations manage contractor engagements in a structured and consistent way.
Key Highlights
Support for businesses engaging off-payroll workers
Employment status assessments
Contractor population and labour supply chain reviews
RSBC supports contractors who operate through limited companies and need ongoing help with IR35 compliance alongside their accounting responsibilities. Their service covers employment status, tax obligations and company administration, giving contractors a single point of support for day-to-day financial matters as well as off-payroll requirements.
Beyond IR35 status, they assist with the wider responsibilities that come with running a contracting business. This includes payroll, VAT, annual accounts, Companies House filings and contractor tax planning, helping clients keep their records organised and meet HMRC deadlines throughout the year.
Address: 11 Approach Rd, Raynes Park, London, SW20 8BA
Phone: 020 8544 9355
Gorilla Accounting
Gorilla Accounting focuses on accounting services for contractors, freelancers and limited companies, with IR35 support forming part of its contractor offering. Their approach combines contractor accounting with tax compliance, helping clients manage their company obligations while working under different contract arrangements.
For contractors operating through a personal service company, IR35 sits alongside the wider financial administration of the business. Clients can use the same adviser for payroll, tax returns, annual accounts and ongoing accounting support, making IR35 one part of a broader contractor accounting service.
Address: Belmont Suite, Paragon Business Park, Chorley New Road, Horwich, Bolton BL6 6HG
Phone: 0330 107 9674
Clearcut Accounting
Clearcut Accounting assists contractors, consultants and businesses with IR35 contract reviews and employment status assessments. Their approach combines a review of contractual terms with an assessment of working practices, recognising that both are important when determining whether an engagement falls inside or outside IR35.
Their support extends to organisations that engage contractors as well as individual contractors themselves. In addition to status reviews, they help businesses prepare Status Determination Statements, review contractor engagement processes and deal with HMRC compliance requirements where off-payroll rules apply.
Smith Butler works with contractors, consultants and businesses that need support with IR35 alongside their wider accounting and tax responsibilities. Their services cover employment status reviews, contractor accounting and tax compliance, with experience across sectors where off-payroll working is common.
IR35 forms part of a broader accounting service that includes payroll, VAT, bookkeeping and business tax advice. They also assist clients with contract reviews and ongoing compliance, helping contractors and businesses manage their obligations as working arrangements change.
Address: Sapper Jordan Rossi Park, Otley Road, Baildon, Bradford, BD17 7AX
Phone: 01274 588115
Treetops Chartered Accountants
Treetops Chartered Accountants supports contractors, freelancers and personal service companies with IR35 compliance as part of its wider accounting services. Their work covers employment status, contractor tax obligations and the practical impact of the off-payroll working rules on different contract arrangements.
Clients can combine IR35 advice with everyday accounting support, making it easier to manage payroll, tax returns and company compliance in one place. They also assist contractors with status assessments and explain the financial implications of contracts that fall inside or outside IR35.
Key Highlights
Support for contractors and personal service companies
Nasa Accountants works with contractors, freelancers and self-employed professionals who need support with IR35 and off-payroll working rules. Their service focuses on reviewing contracts and working practices to assess employment status and help clients meet their tax responsibilities.
Alongside status assessments, they examine the practical details of each engagement to identify factors that may affect an IR35 decision. This allows contractors to deal with compliance issues before entering new contracts or continuing existing assignments.
Ellacotts advises businesses on preparing for the off-payroll working rules through workforce assessments and IR35 compliance reviews. Their approach focuses on helping organisations understand how contractor engagements are managed and whether existing processes meet current HMRC requirements.
Each assessment considers contractor populations, engagement procedures and employment status decisions before recommending practical improvements where needed. They also advise contractors on how the rules may affect individual engagements, supporting both businesses and off-payroll workers during the compliance process.
Address: Countrywide House, 23 West Bar Street, Banbury, Oxfordshire, OX16 9SA
Phone: +44 (0)1295 250401
Conclusion
Choosing an IR35 service provider depends on the type of support you need. Some firms focus on contractors and freelancers, while others work primarily with businesses that engage off-payroll workers. The right choice may also depend on whether you need a one-off contract review, ongoing compliance support, employment status assessments or wider accounting and tax services.
This guide is intended to provide an overview of a range of UK firms that offer IR35-related services. Each provider has a different approach, areas of expertise and service offering, so it is worth reviewing them in more detail before deciding which one best matches your requirements.
AC
Written by the Acumon team
Acumon is an ICAEW-registered firm of chartered accountants and registered auditors
based in London, with offices in Pitstone, Aylesbury and Bournemouth. Need advice on
anything covered here? Talk to us.
An internal audit function must be assessed by a qualified, independent assessor at least once every five years. That requirement is Standard 8.4 of the Global Internal Audit Standards, which…
An internal audit function must be assessed by a qualified, independent assessor at least once every five years. That requirement is Standard 8.4 of the Global Internal Audit Standards, which…
An internal audit function must be assessed by a qualified, independent assessor at least once every five years. That requirement is Standard 8.4 of the Global Internal Audit Standards, which…
Read article
Get in Touch
Ready for Accountants Who Move Your Business Forward?
Tell us what you need. Within one business day, a qualified accountant will be in touch to talk it through and give you a clear, fixed-fee quote — no obligation.
We use essential cookies to run this site, plus Google Analytics and Google Ads to
understand how visitors use it and measure our advertising — only with your consent. See our
Privacy Policy.
