Tax Dispute Resolution Companies in the UK: Firms and Services Guide
AC
Acumon Chartered Accountants·17 min read
Dealing with an HMRC enquiry or tax dispute can be challenging, whether it involves a routine compliance check, a voluntary disclosure or a more complex investigation. The right advice can help businesses and individuals understand the process, respond to HMRC's requests and work towards a practical resolution while keeping disruption to a minimum.
The UK has many firms that advise on tax disputes, but their experience, areas of focus and approach can vary. Some regularly support large organisations with complex cross-border matters, while others work closely with owner-managed businesses, charities, private clients and family-owned companies. Many also provide guidance on tax governance and compliance to help reduce the likelihood of future disputes.
This guide highlights a selection of UK firms offering tax dispute resolution services. It outlines the areas they cover, the types of HMRC matters they advise on and the services available, giving readers a straightforward overview of the market before exploring each firm in more detail.
Acumon
Acumon is a UK firm of chartered accountants and advisors providing tax dispute resolution services to companies and individuals across the UK.
The firm works with organisations ranging from owner-managed businesses through to larger corporate groups, as well as private individuals. Tax dispute resolution services are designed to support clients in managing tax enquiries, resolving disputes and maintaining compliance with UK tax legislation.
Acumon provides tax services including tax compliance, corporation tax advice, personal tax planning and advisory support. Tax dispute resolution work is delivered through a structured approach focused on clear communication, accurate information and practical advice throughout the process.
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, supporting clients with international structures and cross-border reporting requirements.
Tax disputes and enquiries can arise for businesses and individuals for a variety of reasons. Obtaining professional support can help organisations respond effectively, maintain accurate records and manage ongoing tax compliance requirements.
Acumon works with business owners, finance teams and private clients to support tax compliance while helping organisations strengthen financial reporting, governance arrangements and financial controls.
Tax Dispute Resolution Capabilities
Acumon provides tax dispute resolution services across a wide range of clients.
These include:
owner-managed businesses
growing companies
UK corporate groups
private individuals
companies requiring tax compliance support
organisations with ongoing tax obligations
Tax dispute resolution 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 tax dispute resolution services, Acumon provides a range of services that support financial reporting and governance.
These include:
tax dispute resolution services
statutory external audit
group and subsidiary audits
tax compliance and corporation tax advice
Public Interest Entity (PIE) audits
charity and not-for-profit audit
personal tax planning
internal audit and governance reviews
risk management and compliance support
Tax dispute resolution work is often delivered alongside discussions with management regarding tax compliance, financial reporting and accounting processes.
Many organisations and individuals seek professional support when responding to tax enquiries, reviewing compliance obligations or managing complex tax matters.
Acumon works with clients that are:
improving tax compliance
strengthening financial reporting
reviewing tax obligations
supporting business growth
enhancing financial controls
Early engagement can help ensure that tax matters are managed efficiently while supporting ongoing compliance with regulatory requirements.
Address: 1-2 Craven Road, Ealing, London, W5 2UA, UK
Phone: 020 8567 3451
PwC
PwC approaches tax dispute resolution as part of a wider tax risk and governance framework. Their work covers the full lifecycle of a dispute, from preventing issues before they arise through to negotiations, alternative dispute resolution and litigation where necessary. The firm brings together specialists from tax, legal, accounting, economics, technology and former HMRC professionals, reflecting the broad range of issues that can arise during an enquiry.
As tax rules continue to evolve and HMRC increases its focus on governance and supporting evidence, PwC places emphasis on preparing organisations for greater scrutiny. Alongside resolving existing disputes, they advise businesses on tax governance, documentation and risk management to help reduce the likelihood of future challenges. Their experience spans domestic and international tax matters, including complex enquiries such as R&D tax relief claims.
Key Highlights
Tax dispute resolution across the full dispute lifecycle
Focus on tax governance, compliance and risk management
Experience with HMRC enquiries, negotiations and litigation
Multidisciplinary team including former HMRC inspectors
Support for UK and international organisations
Covers both dispute prevention and resolution
Services
Tax dispute resolution
HMRC enquiries and investigations
Alternative dispute resolution (ADR)
Tax risk management and governance
R&D tax enquiry support
Tax litigation support
Legal advisory for tax disputes
Dispute prevention strategies
Contact Information
Website: www.pwc.co.uk
Facebook: www.facebook.com/PwCUK
LinkedIn: www.linkedin.com/company/pwc-uk
Instagram: www.instagram.com/pwc_uk
Address: 1 Embankment Place, London, WC2N 6RH, United Kingdom
Phone: +44 (0)20 7583 5000
Moore Kingston Smith
Moore Kingston Smith focuses on supporting businesses and individuals through HMRC enquiries, investigations and tax disputes. Their tax dispute resolution team deals with matters ranging from routine tax enquiries to more complex investigations under Code of Practice 8 (COP8) and Code of Practice 9 (COP9). The firm's approach centres on managing communication with HMRC while helping clients understand each stage of the process and the options available.
Different types of disputes often require different routes to resolution, whether through voluntary disclosure, informal discussions, mediation or formal appeals. Moore Kingston Smith reflects this by offering support across each stage of a case, including Alternative Dispute Resolution where appropriate. Their work also extends to helping clients respond to changing HMRC compliance activity, with practical guidance on issues such as nudge letters, overseas income enquiries and tax investigations.
Key Highlights
Experience across HMRC enquiries and tax investigations
Covers COP8 and COP9 cases
Support with voluntary disclosures and HMRC negotiations
Advice on Alternative Dispute Resolution
Works with businesses and private clients
Focus on managing disputes from enquiry through to resolution
RSM UK advises clients dealing with HMRC enquiries, tax investigations and disputes across a range of personal and business tax matters. Their tax dispute resolution team includes chartered tax advisers alongside former HM Inspectors of Taxes, giving them experience of both the technical aspects of tax legislation and HMRC's investigative processes. Support is available for organisations already under enquiry as well as those looking to disclose historic tax issues before HMRC raises them.
Every dispute follows its own course, so the firm's work covers several possible routes to resolution. This includes handling investigations, managing voluntary disclosures and representing clients during disputes that may progress to the tax tribunal. Alongside resolving current issues, RSM UK regularly publishes guidance on new compliance activity and changes in HMRC's approach, helping businesses stay informed about emerging tax risks.
Key Highlights
Supports businesses and individuals in HMRC disputes
Team includes former HM Inspectors of Taxes
Experience with voluntary disclosures
Advises on tax tribunal disputes
Covers personal and business tax matters
Regular insight into HMRC compliance developments
Services
HMRC investigations
Tax dispute resolution
Voluntary tax disclosures
Tax tribunal support
HMRC enquiry management
Appeals against HMRC decisions
Tax compliance advisory
Resolution of historic tax issues
Contact Information
Website: www.rsmuk.com
LinkedIn: www.linkedin.com/company/rsm-uk
Instagram: www.instagram.com/rsm.uk
Address: 4th Floor, The Capitol, 431 Union Street,Aberdeen, AB11 6DA
Phone: +44 (0)1224 321133
BDO
BDO handles tax disputes covering everything from compliance checks and technical enquiries to complex fraud allegations and tribunal proceedings. Their tax dispute resolution practice works across personal and corporate tax matters, combining tax specialists with professionals from areas such as VAT, employment tax, accounting and valuation where additional expertise is needed during a case.
Some disputes can be resolved through negotiation, while others require formal appeals or litigation. BDO supports clients throughout that process, including Alternative Dispute Resolution, HMRC compliance checks and investigations under Codes of Practice 8 and 9. The firm also advises on penalty regimes, voluntary disclosures and the practical steps involved in responding to HMRC enquiries before they become more significant disputes.
Key Highlights
Covers a broad range of HMRC disputes and investigations
Multidisciplinary tax dispute resolution team
Experience with compliance checks and penalty matters
Supports Alternative Dispute Resolution and tribunal cases
Advises on historic tax issues and voluntary disclosures
S&W deals with tax disputes involving HMRC by supporting clients through each stage of the resolution process, from informal discussions to tribunal proceedings where required. Their work covers disagreements over tax returns, technical interpretations and compliance matters, with guidance tailored to the circumstances of each case. The firm also advises on the different routes available, including independent HMRC reviews and Alternative Dispute Resolution.
Not every dispute follows the same path, so S&W assesses whether mediation, negotiation or formal litigation is the most appropriate option. Where cases progress beyond discussions with HMRC, the team assists with preparing evidence, working alongside tax counsel and representing clients throughout tribunal proceedings. Their experience also includes expert witness services in tax-related legal disputes.
Key Highlights
Advises on HMRC disputes across different stages of the process
Experience with Alternative Dispute Resolution and mediation
Supports tribunal and litigation cases
Assists with HMRC reviews and appeals
Tax expert witness experience
Covers both personal and business tax disputes
Services
Tax dispute resolution
HMRC tax enquiries
Alternative Dispute Resolution (ADR)
HMRC reviews and appeals
Tax tribunal support
Litigation preparation
Tax expert witness services
Voluntary disclosures
Contact Information
Website: www.swgroup.com
Twitter: x.com/S_W_Group
LinkedIn: www.linkedin.com/company/swgroupuk
Address: 45 Gresham Street, London EC2V 7BG
Phone: +44(0)204 617 55 00
HaysMac
HaysMac supports businesses, private clients, charities and trusts involved in HMRC enquiries and tax disputes. Their tax disputes and resolutions team advises on a wide range of matters, including disclosures, investigations, Code of Practice 9 enquiries and appeals. The focus is on applying tax legislation to the specific circumstances of each case while maintaining clear communication throughout the process.
Cases often involve detailed discussions with HMRC alongside technical and financial analysis. HaysMac manages negotiations, prepares settlement proposals where appropriate and continues to support clients if a dispute progresses further. The firm also places emphasis on explaining the process in straightforward terms, helping clients understand each stage without unnecessary complexity.
Key Highlights
Advises private clients, businesses, charities and trusts
KPMG approaches tax disputes through a combination of legal and tax expertise, covering contentious matters across corporate tax, VAT, customs, direct taxes and public law. Their tax disputes and litigation practice includes solicitors, barristers, former HMRC professionals and accredited mediators, allowing them to advise on disputes that range from compliance enquiries to complex litigation.
The firm's work extends beyond resolving existing disputes by helping organisations manage tax risk before issues become contentious. Where enquiries arise, KPMG supports clients with evidence gathering, responding to information requests, negotiating with tax authorities and pursuing Alternative Dispute Resolution where suitable. If litigation becomes necessary, the team represents clients through tribunal and court proceedings while coordinating legal and tax advice across the wider case.
Key Highlights
Combines legal and tax expertise in dispute resolution
Covers corporate tax, VAT, customs and direct taxes
Team includes former HMRC professionals and accredited mediators
Advises on dispute prevention and tax risk management
Supports Alternative Dispute Resolution and litigation
MHA approaches tax dispute resolution as part of a wider tax risk and compliance service, supporting businesses and individuals facing HMRC enquiries, investigations and disputes. Their team advises on cases involving tax reviews, compliance issues, tribunal proceedings and direct communication with HMRC, with the aim of helping clients understand the position taken by the tax authority and respond with appropriate evidence and documentation.
No two disputes develop in exactly the same way, so MHA adapts its approach to the circumstances of each case. Alongside resolving existing issues, the firm carries out tax reviews designed to identify potential risks before they become formal enquiries. Support extends from routine compliance matters through to tax tribunal representation, allowing clients to deal with different stages of a dispute through one advisory team.
Key Highlights
Advises businesses and individuals on HMRC disputes
Covers tax reviews, investigations and compliance matters
Crowe focuses on helping clients manage tax enquiries, investigations and disputes with HMRC across a wide range of tax matters. Their tax disputes and investigations team assists with voluntary disclosures, statutory enquiries, Code of Practice investigations and disagreements over tax assessments or penalties. The emphasis is on guiding clients through the process while managing discussions with HMRC on their behalf.
Some cases involve correcting historic tax issues, while others begin after HMRC opens an enquiry or sends a compliance letter. Crowe deals with both situations, including offshore disclosures, cryptoasset disclosures and landlord disclosure campaigns. The firm also advises on mediation, tribunal matters and specialist tax disputes where additional technical support is required.
Key Highlights
Advises on HMRC enquiries and investigations
Covers voluntary disclosures and statutory enquiries
Address: 3rd Floor, St George's House, 56 Peter Street, Manchester M2 3NQ
Phone: +44 (0)161 214 7500
Forvis Mazars
Forvis Mazars advises businesses and individuals involved in HMRC enquiries that range from routine compliance checks to more complex tax investigations. Their tax dispute resolution practice covers matters such as Code of Practice 8 and 9 cases, R&D enquiries, discovery assessments and offshore tax issues. The firm supports a broad client base, including sole traders, partnerships, companies, trusts and high-net-worth individuals.
Every enquiry brings its own challenges, so the team focuses on explaining the process clearly while helping clients understand the issues HMRC is examining. Where historic inaccuracies need to be addressed, they assist with voluntary disclosures and discussions over penalties. If a dispute progresses further, support continues through appeals, Alternative Dispute Resolution and litigation where required.
Key Highlights
Advises individuals and businesses on HMRC disputes
Experience with COP8, COP9 and R&D enquiries
Covers offshore tax matters and discovery assessments
Supports voluntary disclosures and appeals
Assists with Alternative Dispute Resolution
Handles disputes from enquiry through to litigation
Address: 30 Old Bailey, London, EC4M 7AU, United Kingdom
Phone: +44 (0) 20 7063 4000
Price Bailey
Price Bailey supports clients dealing with tax enquiries, investigations and historic tax issues across both personal and business tax matters. Their tax dispute resolution team advises sole traders, companies, partnerships, charities, trustees and individual taxpayers, helping them manage HMRC enquiries while reducing disruption to day-to-day activities.
Some matters involve routine enquiries, while others develop into more technical investigations or formal appeals. Price Bailey assists with voluntary disclosures, negotiations over penalties, responses to HMRC nudge letters and tribunal proceedings where necessary. The firm also offers guidance for clients who want to review potential tax risks before an enquiry arises.
Key Highlights
Advises businesses and private clients on HMRC disputes
Experience with routine and complex tax investigations
Supports voluntary disclosures and penalty negotiations
Represents clients during ADR and tribunal proceedings
Deloitte approaches disputes through a multidisciplinary advisory model that combines legal, forensic, accounting and valuation expertise. Although their published information focuses on disputes and litigation across a broad range of business matters, this approach is relevant to tax disputes where financial analysis, technical evidence and legal support may all form part of the resolution process.
When disputes become more complex or involve formal legal proceedings, Deloitte brings together specialists from different disciplines to examine evidence, support litigation and provide expert opinions where required. Their services are designed for organisations dealing with significant commercial, regulatory or financial disputes that require coordinated technical advice.
Key Highlights
Multidisciplinary disputes and litigation practice
Combines legal, forensic and financial expertise
Supports complex commercial and tax-related disputes
Experience with litigation support and expert evidence
Focus on dispute resolution and risk management
Advises organisations across multiple industries
Services
Dispute advisory
Litigation support
Expert witness services
Expert determination
Forensic investigations
Financial analysis
Valuation support
Regulatory dispute advisory
Contact Information
Website: www.deloitte.com
Facebook: www.facebook.com/deloitteuk
Twitter: x.com/deloitteuk
LinkedIn: www.linkedin.com/company/deloitte
Address: 1 New Street Square, London, EC4A 3HQ, United Kingdom
Phone: +44 (0)20 7936 3000
Resolution Tax
Resolution Tax is a specialist tax advisory firm focused on tax disputes, investigations and consulting for corporate and private clients. Their practice covers UK and international tax matters, with advice led by senior tax advisers and tax lawyers who deal with technically complex and commercially sensitive cases.
Many of the matters they handle involve disputes where strategic planning and careful communication are just as important as technical tax knowledge. Alongside formal tax disputes, the firm advises on investigations and wider tax issues that may carry financial or reputational implications, helping clients navigate each stage of the process with a structured approach.
Key Highlights
Specialist tax disputes and investigations practice
Kreston Reeves advises businesses and private clients on tax disputes, investigations and HMRC enquiries across a range of tax matters. Their approach combines technical tax knowledge with practical guidance, helping clients deal with enquiries from the earliest stages through to formal disputes where additional representation is needed. The firm works to clarify HMRC's concerns, review the available evidence and develop a response that reflects the facts of the case.
Some disputes can be settled through ongoing discussions with HMRC, while others require appeals or more formal proceedings. Kreston Reeves supports clients throughout that process, including voluntary disclosures, negotiations and tribunal matters where appropriate. Alongside resolving current issues, the firm helps clients identify areas that may increase the likelihood of future enquiries, allowing them to strengthen their tax compliance and governance.
Key Highlights
Advises businesses and individuals on HMRC disputes
Supports tax enquiries and investigations
Experience with voluntary disclosures and appeals
Assists with tribunal proceedings where required
Focus on tax compliance and governance
Provides practical support throughout the dispute process
Services
Tax dispute resolution
HMRC enquiries
Tax investigations
Voluntary disclosures
Appeals against HMRC decisions
Tax tribunal support
HMRC negotiations
Tax governance advice
Contact Information
Website: www.krestonreeves.com
Twitter: x.com/KrestonReeves
LinkedIn: www.linkedin.com/company/kreston-reeves
Address: 2nd Floor, 168 Shoreditch High Street, London, E1 6RA
Phone: +44 (0)330 124 1399
Conclusion
Choosing a tax dispute resolution provider is not simply a question of finding the largest firm or the widest range of services. The right choice often depends on the nature of the dispute, the taxes involved and the level of HMRC engagement. Some firms have extensive experience with complex corporate investigations and cross-border matters, while others focus on supporting owner-managed businesses, charities or private individuals through enquiries and disclosures.
It is also worth considering how a firm approaches communication, case management and dispute resolution. Depending on the circumstances, support may involve negotiating directly with HMRC, preparing a voluntary disclosure, representing a client during Alternative Dispute Resolution or handling an appeal before the tax tribunal.
This guide is intended to provide an overview of firms offering tax dispute resolution services in the UK. By comparing their areas of expertise and the types of matters they regularly handle, businesses and individuals can build a clearer picture of the available options and identify a provider whose experience is suited to their particular situation.
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.
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