Cross-border tax matters can affect businesses expanding internationally, overseas groups entering the UK, internationally mobile individuals and families with assets or income in several jurisdictions. Advice may cover double taxation, residence, permanent establishments, transfer pricing, withholding taxes, international structuring, global mobility and overseas compliance. This guide provides a practical overview of cross-border tax services in London rather than ranking the firms.
Acumon
Acumon is a UK firm of chartered accountants and registered auditors providing cross-border and international tax services to businesses, individuals and international groups. Its International Tax service covers overseas businesses establishing UK operations, UK companies expanding abroad, permanent establishment risks, double taxation, withholding taxes, cross-border structuring and international tax compliance. The firm also advises internationally mobile individuals on statutory residence, split-year treatment and the Foreign Income and Gains regime.
The firm works with organisations ranging from growing owner-managed businesses and charities through to larger corporate groups and regulated entities. Audit engagements are delivered in accordance with International Standards on Auditing (UK) and supported by a structured risk-based audit methodology.
Acumon holds a Public Interest Entity (PIE) audit licence, allowing the firm to audit listed companies and other entities subject to enhanced regulatory oversight in the United Kingdom. PIE audits are subject to additional regulatory supervision and quality requirements.
In addition to its UK audit registration, Acumon also holds audit licences in several international financial centres, including the Cayman Islands, British Virgin Islands (BVI), Jersey and Isle of Man. These licences enable the firm to support international corporate groups where entities are located across multiple jurisdictions.
International group structures frequently involve a combination of UK operating companies and offshore holding entities, particularly in sectors such as investment management, technology, energy and international trade. Coordinating audit and assurance work across these structures requires familiarity with cross-border financial reporting, group consolidation processes, governance arrangements and internal control environments.
For cross-border tax clients, Acumon’s wider tax, accounting and audit capabilities allow international tax questions to be considered alongside UK reporting and compliance requirements. The firm can advise on whether overseas activity creates a UK taxable presence, the choice between a branch and subsidiary, intercompany arrangements, double-tax relief and the tax position of individuals moving into or out of the UK.
Cross-Border Tax Capabilities
Acumon provides cross-border tax 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
Cross-border tax engagements are typically led by senior tax 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
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
- Website: acumon.com
- Phone: 020 8567 3451
- E-mail: [email protected]
- Address: 1-2 Craven Road, Ealing, London, W5 2UA, UK
Blick Rothenberg
Blick Rothenberg has a dedicated international tax practice advising multinational organisations on international tax strategy and cross-border transactions. Its corporate work includes reorganisations, international expansion and cross-border mergers and acquisitions, while related services cover transfer pricing and global mobility. The firm also has established US-UK capabilities for individuals and businesses whose tax affairs span both jurisdictions. International work can be coordinated from its London office through the firm’s wider international network.
Key Facts
- Ideal for: International businesses, multinational groups and internationally connected individuals
- Core services: International tax planning, cross-border transactions, reorganisations and international expansion
- Related capability: Transfer pricing and global mobility
- International coverage: Corporate and private client cross-border matters
Contact Information:
- Website: www.blickrothenberg.com
- Twitter: x.com/BlickRothenberg
- LinkedIn: www.linkedin.com/company/blickrothenberg
- Instagram: www.instagram.com/blickrothenberg
- Address: 16 Great Queen Street, Covent Garden, London, WC2B 5AH
- Phone: +44 (0)20 7486 0111
PKF Littlejohn
PKF Littlejohn provides international tax advice to established multinational groups as well as privately owned businesses entering overseas markets. Its international tax team advises on taxable permanent establishments, overseas operations, cross-border acquisitions and disposals, withholding taxes, profit repatriation and foreign compliance. Transfer pricing and international employee taxation are also covered, while VAT, GST and customs advice can be coordinated where cross-border trading creates indirect tax obligations.
Key Facts
- Ideal for: Businesses establishing or managing operations across several countries
- Core services: Cross-border tax planning, overseas tax obligations and international structuring
- Corporate capability: International M&A, profit repatriation and foreign market entry
- Related services: Transfer pricing, global mobility and international indirect tax
Contact Information:
- Website: www.pkf-l.com
- E-mail: [email protected]
- Twitter: x.com/PKF_Littlejohn
- LinkedIn: www.linkedin.com/company/littlejohn
- Instagram: www.instagram.com/pkf.littlejohn
- Address: 30 Churchill Place, London, E14 5RE
- Phone: 020 7516 2200
Saffery
Saffery works with companies and individuals whose financial affairs extend beyond the UK. Corporate international tax services include advice for overseas companies establishing UK branches or subsidiaries and UK companies expanding abroad, together with permanent establishments, transfer pricing, controlled foreign company rules, holding structures and withholding taxes. The private client team handles internationally mobile individuals, overseas assets and wider cross-border planning, supported by the firm’s Nexia network.
Key Facts
- Ideal for: International families, entrepreneurs and privately owned or multinational businesses
- Core services: International corporate tax and international private client tax
- Corporate coverage: Permanent establishments, transfer pricing and cross-border structures
- Private client coverage: International mobility, overseas interests and UK tax planning
Contact Information:
- Website: www.saffery.com
- E-mail: [email protected]
- LinkedIn: www.linkedin.com/company/saffery
- Instagram: www.instagram.com/saffery_uk
- Address: 71 Queen Victoria Street, London, EC4V 4BE
- Phone: 020 7841 4000
Buzzacott
Buzzacott combines business tax services with a specialist US-UK tax practice. Its international business tax work covers cross-border compliance, transfer pricing and tax-efficient structures for companies operating internationally. For individuals, entrepreneurs and trusts with US connections, the firm provides coordinated UK and US tax compliance and planning, including advice on businesses, pensions, trusts and international relocation. The practice operates from a single City of London office.
Key Facts
- Ideal for: Businesses with international tax issues and clients with US-UK connections
- Core services: International business tax, US-UK tax compliance and planning
- Corporate capability: Transfer pricing and cross-border structuring
- Private client capability: International relocation, trusts, pensions and dual-jurisdiction reporting
Contact Information:
- Website: www.buzzacott.co.uk
- E-mail: [email protected]
- Facebook: www.facebook.com/people/Buzzacott/100066357656648
- LinkedIn: www.linkedin.com/company/buzzacott
- Address: 130 Wood Street, London, EC2V 6DL
- Phone: 020 7556 1200
Moore Kingston Smith
Moore Kingston Smith provides international tax support for businesses expanding into new markets, restructuring multinational operations or managing tax compliance across jurisdictions. Services include cross-border tax planning, international corporate structuring and transfer pricing. The firm also maintains a specialist US-UK tax service that covers business tax returns, treaty issues, foreign account reporting and compliance for people and businesses connected to both countries.
Key Facts
- Ideal for: International businesses and clients with specific US-UK tax requirements
- Core services: International tax planning, structuring and transfer pricing
- US-UK services: Treaty advice, tax compliance and foreign account reporting
- Related capability: Global mobility and outsourced accounting
Contact Information:
- Website: mooreks.co.uk
- Twitter: x.com/MooreKSLLP
- LinkedIn: www.linkedin.com/company/moore-kingston-smith
- Address: 6th Floor, 9 Appold Street, London, EC2A 2AP
- Phone: 020 4582 1000
Forvis Mazars
Forvis Mazars provides global tax services to multinational, mid-market and growing businesses as well as international private clients. Its business offering covers corporate structuring, global compliance, transfer pricing, Pillar Two, global mobility, VAT and indirect tax, international transactions and tax incentives. Private client services include cross-border planning, residence, expatriate taxation, double-tax considerations and advice for people holding assets or structures across several jurisdictions.
Key Facts
- Ideal for: Multinational businesses and private clients with multi-jurisdictional tax requirements
- Core services: Global tax compliance, international structuring and transfer pricing
- Corporate coverage: Pillar Two, international transactions and global mobility
- Private client coverage: Cross-border planning, residence and double-tax issues
Contact Information:
- Website: www.forvismazars.com
- Twitter: x.com/ForvisMazarsUK
- LinkedIn: www.linkedin.com/company/forvis-mazars-in-the-uk
- Instagram: www.instagram.com/forvismazarsuk
- Address: 30 Old Bailey, London, EC4M 7AU
- Phone: +44 (0)20 7063 4000
RSM UK
RSM UK advises businesses operating internationally on tax strategy, market entry, overseas expansion and ongoing global compliance. Its international tax practice covers the structure of overseas operations, permanent establishments, transfer pricing, international workforce issues and worldwide reporting. The firm can also coordinate corporate, VAT and employment tax requirements through its international network, while its London private client team handles tax matters affecting individuals whose affairs span several countries.
Key Facts
- Ideal for: Businesses expanding internationally or coordinating tax across multiple jurisdictions
- Core services: International tax advisory, structuring and global compliance
- Related capability: Transfer pricing, VAT and global mobility
- Private client support: Cross-border and internationally mobile individual tax matters
Contact Information:
- Website: www.rsmuk.com
- LinkedIn: www.linkedin.com/company/rsm-uk
- Instagram: www.instagram.com/rsm.uk
- Address: 25 Farringdon Street, London, EC4A 4AB
- Phone: 020 3201 8000
MHA
MHA’s International Tax Services practice covers multinational tax compliance and advisory work for companies operating across borders. Services include international tax structuring, transfer pricing, cross-border M&A support, global mobility, withholding tax, permanent establishment and residence risks, global tax reporting and Pillar Two. The London private client team also advises internationally connected individuals on pre-arrival and departure planning, offshore assets and UK tax obligations arising from cross-border structures.
Key Facts
- Ideal for: Multinational businesses and internationally connected private clients
- Core services: International tax compliance, structuring and global tax coordination
- Corporate capability: Cross-border M&A, transfer pricing and Pillar Two
- Private client capability: Pre-arrival, departure and offshore tax planning
Contact Information:
- Website: www.mha.co.uk
- E-mail: [email protected]
- Facebook: www.facebook.com/people/MHA-Accountants/100063452388108
- LinkedIn: www.linkedin.com/company/mha-uk
- Instagram: www.instagram.com/mhaaccountants
- Address: 2 London Wall Place, London, EC2Y 5AU
- Phone: +44 (0)20 7429 4100
Gerald Edelman
Gerald Edelman’s international tax team works with individuals and businesses moving into the UK, investing in the country or expanding internationally. Corporate advice covers branches and subsidiaries, holding structures, profit repatriation, transfer pricing, withholding tax and cross-border VAT. Private client work includes residence, pre-arrival planning, double taxation agreements, offshore structures and internationally held wealth. Multi-jurisdictional assignments can be coordinated through the XLNC international network.
Key Facts
- Ideal for: Owner-managed businesses, international companies and private clients
- Core services: Cross-border corporate and personal tax advice
- Corporate coverage: International structuring, transfer pricing and withholding tax
- Private client coverage: Residence, double taxation and offshore structures
Contact Information:
- Website: www.geraldedelman.com
- E-mail: [email protected]
- Facebook: www.facebook.com/people/Gerald-Edelman/100070621640173
- LinkedIn: www.linkedin.com/company/geraldedelman
- Instagram: www.instagram.com/geraldedelmanuk
- Address: 73 Cornhill, London, EC3V 3QQ
- Phone: 020 7299 1400
SRLV
SRLV provides international tax advice from its London practice for businesses, private clients and internationally mobile individuals. Its work includes withholding tax, worldwide business and wealth structures, companies entering the UK, residency issues, offshore trusts, international property taxation and cross-border tax compliance. Corporate clients can also obtain guidance on transfer pricing and tax issues affecting multinational groups, while private client advice covers overseas assets and people moving between jurisdictions.
Key Facts
- Ideal for: International businesses and individuals with overseas wealth or residency issues
- Core services: International tax, cross-border structuring and withholding tax
- Corporate capability: Multinational tax and transfer pricing
- Private client capability: Residency, offshore trusts and worldwide wealth structuring
Contact Information:
- Website: www.srlv.co.uk
- E-mail: [email protected]
- LinkedIn: www.linkedin.com/company/srlv
- Instagram: www.instagram.com/srlv.llp
- Address: 4th Floor Elsley Court, 20-22 Great Titchfield Street, London, W1W 8BE
- Phone: +44 (0)20 7079 8888
Lubbock Fine
Lubbock Fine supports UK and international businesses with corporate tax compliance and advisory work, including international tax and cross-border planning through the Russell Bedford International network. Its services cover group structures, mergers and acquisitions, transfer pricing, controlled foreign company issues, anti-hybrid rules, UK market entry and international compliance. The private client team also handles international affairs for individuals with overseas interests and coordinates advice with member firms in other jurisdictions where necessary.
Key Facts
- Ideal for: Businesses combining UK corporate tax with international expansion or structuring
- Core services: Corporate and international tax advisory
- International capability: Cross-border advisory and compliance through Russell Bedford International
- Related services: Transfer pricing, M&A tax and UK market entry
Contact Information:
- Website: www.lubbockfine.co.uk
- E-mail: [email protected]
- Facebook: www.facebook.com/lubbockfineaccountants
- Twitter: x.com/lubbockfine
- LinkedIn: www.linkedin.com/company/lubbock-fine
- Address: Paternoster House, 65 St Paul’s Churchyard, London, EC4M 8AB
- Phone: 020 7490 7766
Andersen
Andersen’s London international tax team works with multinational companies, entrepreneurs, high-net-worth individuals, family offices and investment funds. Its practice bridges corporate and personal international taxation and includes cross-border transactions, international investment structures, real estate transactions and profit repatriation. Andersen also has dedicated UK-US tax expertise, including double-taxation issues, internationally held investments and expatriate taxation, with access to other jurisdictions through Andersen Global.
Key Facts
- Ideal for: Private clients, businesses and investment structures with complex international tax requirements
- Core services: Cross-border corporate and personal tax
- Specialist capability: UK-US tax planning and compliance
- Related services: International transactions, investment structures and global mobility
Contact Information:
- Website: uk.andersen.com
- E-mail: [email protected]
- Address: 2 George Yard, London, EC3V 9DH
- Phone: +44 (0)20 7242 5000
A.C.T. London
A.C.T. London is a Mayfair advisory firm working with internationally connected individuals, families, entrepreneurs and business owners. Its dedicated cross-border tax service covers residency and relocation, treaty planning, exit events, withholding tax and ongoing international exposure. Related advisory work includes international wealth and corporate structuring, trusts and fiduciary arrangements, succession planning and tax considerations around acquisitions, disposals and other transactions.
Key Facts
- Ideal for: International families, entrepreneurs and business owners
- Core services: Cross-border tax advisory and international structuring
- Private client coverage: Residence, relocation, wealth and succession planning
- Transaction capability: M&A, exit and tax due diligence advisory
Contact Information:
- Website: act.london
- E-mail: [email protected]
- Facebook: www.facebook.com/ACTGroup2002
- Twitter: x.com/ACT_Group_
- LinkedIn: www.linkedin.com/company/actlondon
- Address: 27 Hill Street, Mayfair, London, W1J 5LP
- Phone: +44 (0)20 7432 6050
US UK Accountants
US UK Accountants focuses specifically on tax and accounting matters spanning the United States and United Kingdom. Its London team supports Americans living in the UK, dual citizens, founders and international businesses with US tax returns, UK Self Assessment, FBAR and FATCA reporting, treaty positions and cross-border tax planning. The firm coordinates reporting across both tax systems, including foreign tax relief and compliance where clients would otherwise have separate UK and US filing obligations.
Key Facts
- Ideal for: Individuals and businesses with direct US-UK tax obligations
- Core services: US and UK tax compliance and cross-border planning
- Specialist reporting: FBAR, FATCA and US expat returns
- Tax planning: US-UK treaty positions and double-tax coordination
Contact Information:
- Website: www.usukaccountants.com
- E-mail: [email protected]
- LinkedIn: www.linkedin.com/company/usukaccountants
- Instagram: www.instagram.com/usukaccountants
- Address: 70 Queen Road, London, E17 8QP
- Phone: +44 333 090 4129
Grant Thornton UK
Grant Thornton UK provides international tax services for businesses ranging from companies making their first overseas expansion to established multinational groups. Its advisers cover cross-border structuring and financing, international tax compliance, Pillar Two, transfer pricing, global mobility and international indirect tax. The firm can also coordinate multi-jurisdictional advice through the Grant Thornton international network, including support with cross-border transactions and restructuring.
Key Facts
- Ideal for: Growing international businesses and multinational groups
- Core services: International tax planning, structuring and compliance
- Corporate capability: Transfer pricing, Pillar Two and overseas expansion
- Related services: Global mobility, international indirect tax and cross-border transactions
Contact Information:
- Website: www.grantthornton.co.uk
- LinkedIn: www.linkedin.com/company/grant-thornton-uk
- Instagram: www.instagram.com/gt_trainees
- Address: 8 Finsbury Circus, London, EC2M 7EA
- Phone: +44 (0)20 7383 5100
Kreston Reeves
Kreston Reeves provides international tax advice to businesses, internationally mobile individuals and private clients from its London and South East practices. Its services include cross-border investment and acquisition structures, international financing, tax residency, VAT and duty, transfer pricing and compliance for transactions spanning several jurisdictions. The firm also supports inbound and outbound individuals with UK tax residence, offshore structures and employment-related tax obligations.
Key Facts
- Ideal for: International businesses, entrepreneurs and internationally mobile private clients
- Core services: Cross-border tax advisory, international structuring and compliance
- Corporate capability: Transfer pricing, international acquisitions and financing structures
- Private client capability: Tax residence, inbound and outbound planning and offshore structures
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: 020 7382 1820
Conclusion
Cross-border tax requirements vary considerably depending on whether the underlying issue involves an individual moving between countries, a UK business expanding overseas, an international group establishing UK operations or a transaction involving entities in several jurisdictions. Some advisers cover both private client and corporate matters, while others concentrate on areas such as US-UK taxation, international business structuring, transfer pricing or global compliance.
The appropriate provider therefore depends on the jurisdictions involved and the work required. Residence and double-tax questions call for different expertise from transfer pricing, permanent establishment reviews, Pillar Two compliance or international M&A, so defining the tax exposures and reporting obligations first can make it easier to compare suitable firms.