Cross-border tax can involve much more than filing returns in two countries. Businesses and individuals may need help with tax residence, treaties, withholding tax, transfer pricing, overseas expansion, international employment and the interaction between UK and foreign tax systems. The firms below provide different combinations of these services, so this is a practical selection rather than a ranking.
Acumon
Acumon is a UK firm of chartered accountants and tax advisers providing international and cross-border tax services to companies, individuals, and international corporate groups.
The firm works with organisations ranging from inbound overseas businesses establishing UK operations and UK companies expanding internationally through to UK subsidiaries of international groups, owner-managed businesses with cross-border interests, and internationally mobile individuals.
Cross-border tax advice is delivered by a team that includes Chartered Tax Advisors and professionals with prior HMRC experience, focusing on practical structuring, treaty relief, residence rules, and compliance.
Acumon advises across the full range of cross-border situations: structuring UK operations for overseas groups (subsidiary, branch or permanent establishment analysis), relieving double taxation through the UK’s extensive network of double taxation agreements (covering over 130 countries), handling treaty claims, withholding tax reductions and foreign tax credits, and coordinating UK compliance with overseas advisors.
The firm also supports residence and split-year analysis under the Statutory Residence Test, the 4-year Foreign Income and Gains (FIG) regime for qualifying new UK residents, intercompany arrangements reviewed against the arm’s-length standard, and related employment tax, PAYE and cross-border VAT matters.
International group structures frequently involve a combination of UK operating companies and overseas entities. Coordinating tax work across these structures requires familiarity with treaty provisions, permanent establishment risk, transfer pricing at a proportionate scale, and the interaction of UK and foreign tax systems.
Acumon works with finance teams, boards and individuals to support statutory tax compliance requirements while also helping organisations and people manage double taxation risk, strengthen cross-border reporting processes, and maintain defensible positions as they grow or relocate.
Cross-Border Tax Capabilities:
Acumon provides international and cross-border tax services across a wide range of organisational structures and situations.
These include:
- Inbound overseas businesses establishing in the UK and UK subsidiaries of international groups
- UK companies expanding overseas and groups with cross-border income streams
- Double taxation relief, treaty analysis, residence planning and foreign tax credit claims
- Cross-border individuals, expatriates and new UK residents (including Statutory Residence Test, split-year treatment and the 4-year FIG regime)
- Intercompany arrangements, permanent establishment assessments and proportionate transfer pricing support
- Coordination of UK tax compliance with overseas advisors and head-office reporting requirements
These services allow the firm to support groups and individuals operating across the UK and multiple international jurisdictions.
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:
- Website: acumon.com
- Phone: 020 8567 3451
- E-mail: [email protected]
- Address: 1-2 Craven Road, Ealing, London, W5 2UA, UK
Grant Thornton UK
Grant Thornton works with businesses at different stages of international expansion, from a first move outside the UK to established operations across several jurisdictions. Its international tax practice covers overseas structuring, corporate residence, permanent establishment risk, withholding tax, tax treaties and transfer pricing.
The firm also combines corporate international tax with global mobility and indirect tax work. For companies with operations in several countries, its Global Compliance Reporting Solutions service provides another route for coordinating reporting obligations across jurisdictions. Grant Thornton also has a dedicated UK-US tax service for individuals, entrepreneurs and families with obligations in both countries.
Key Facts:
- Ideal for: Businesses expanding internationally and groups managing tax across multiple jurisdictions
- Core services: International tax structuring, transfer pricing, corporate residence and treaty analysis
- Additional support: Global mobility, international indirect tax and global compliance
- Cross-border focus: Inbound and outbound business expansion
- International reach: Grant Thornton network across more than 150 markets
Contact Information:
- Website: www.grantthornton.co.uk
- LinkedIn: www.linkedin.com/company/grant-thornton-uk
- Instagram: www.instagram.com/gt_trainees
- Address: 7th Floor, City Square House, 11 Wellington Street, Leeds, LS1 4DL
- Phone: +44 (0)113 245 5514
Bishop Fleming
Bishop Fleming advises both businesses and individuals on international tax matters. Its corporate work covers inbound and outbound investments, overseas branches and subsidiaries, transfer pricing, cross-border transactions, double taxation agreements and international funding structures.
For individuals, the firm handles tax questions connected with moving to or from the UK, residence and overseas interests. Bishop Fleming is also a member of Kreston Global, giving its UK team access to firms in other jurisdictions when an assignment requires coordinated advice outside the UK.
Key Facts:
- Ideal for: Owner-managed businesses, international companies and individuals with overseas tax exposure
- Core services: International business tax, personal tax, transfer pricing and double taxation advice
- Business support: Overseas investment, branch and subsidiary creation and global transaction structures
- Individual support: Residence and tax planning around international moves
- UK presence: Nine UK offices
Contact Information:
- Website: www.bishopfleming.co.uk
- Facebook: www.facebook.com/people/Life-at-Bishop-Fleming/100093464198343
- Twitter: x.com/BishopFlemingUK
- LinkedIn: www.linkedin.com/company/bishop-fleming-chartered-accountants
- Instagram: www.instagram.com/bishopfleminguk
- Address: 55 Colmore Row Birmingham B3 2AA
- Phone: 03333 219000
Moore Kingston Smith
Moore Kingston Smith provides international tax services for businesses operating across borders, including companies entering new markets and groups changing their international structure. Its work covers cross-border tax planning, corporate structures, withholding taxes and transfer pricing.
The firm also has a specialist UK-US tax team with professionals holding UK and US qualifications. That service covers matters including tax return compliance, foreign bank account reporting, tax credits and the application of the UK-US double tax treaty. Access to the Moore Global network extends its support to projects involving additional jurisdictions.
Key Facts:
- Ideal for: International companies and clients with UK-US tax requirements
- Core services: International tax planning, transfer pricing and corporate structuring
- UK-US services: Dual-jurisdiction tax compliance and treaty matters
- Cross-border focus: Expansion, restructuring and multinational compliance
- International network: Moore Global
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: +44 (0)20 4582 1000
Sheltons Group
International taxation is a central part of Sheltons Group’s practice. The firm works with internationally operating businesses and individuals and maintains offices in several jurisdictions, including the UK.
For individuals, its cross-border work includes treaty residence, tax issues arising when moving between countries and dual tax return filings. Its UK practice also handles corporate and personal compliance alongside international tax advice, which can suit clients that need ongoing UK support as well as guidance on the interaction between jurisdictions.
Key Facts:
- Ideal for: Internationally mobile individuals and businesses operating in several countries
- Core services: International tax advice, local tax compliance and cross-border planning
- Individual services: Treaty residence, relocation tax issues and dual filings
- International presence: Offices in multiple jurisdictions, including the UK
- UK location: London
Contact Information:
- Website: www.sheltonsgroup.com
- E-mail: [email protected]
- Facebook: www.facebook.com/SheltonsGroup
- LinkedIn: www.linkedin.com/company/sheltons-group
- Phone: +44 20 389 74 888
- Address: 25 Eccleston Place, London, SW1W 9NF, United Kingdom
Kreston Reeves
Kreston Reeves has an international tax practice serving companies, investors and private clients. Business services include structuring investments and acquisitions across jurisdictions, international financing arrangements, VAT and duty matters, and support for cross-border transactions.
Transfer pricing is another part of the practice, including benchmarking, documentation and dispute-related support. For individuals, the team advises on UK tax residence, inbound and outbound moves and related personal tax obligations. Kreston Reeves works with other Kreston Global member firms when local expertise is required abroad.
Key Facts:
- Ideal for: Growing businesses, international investors and private clients
- Core services: International structuring, transfer pricing, cross-border transactions and personal international tax
- Indirect tax support: International VAT and duty
- UK presence: Offices across London and the South East
- International network: Kreston Global
Contact Information:
- Website: www.krestonreeves.com
- Twitter: x.com/KrestonReeves
- LinkedIn: www.linkedin.com/company/kreston-reeves
- Phone: +44 (0)330 124 1399
- Address: 2nd Floor, 168 Shoreditch High Street, London E1 6RA
UHY Hacker Young
UHY Hacker Young supports businesses entering overseas markets and companies managing operations across several jurisdictions. Its internationalisation services cover tax structuring, direct and indirect taxation, transfer pricing, customs and local compliance requirements.
The firm can also assist individuals planning temporary or permanent moves abroad. Cross-border assignments can be coordinated through UHY International, giving UK clients access to accounting and tax professionals in overseas markets rather than requiring them to source advisers independently in every country.
Key Facts:
- Ideal for: SMEs and businesses planning international expansion
- Core services: International tax planning, transfer pricing, indirect tax and customs
- Individual support: Tax planning for overseas moves
- Delivery model: UK advice combined with overseas member firms
- UK presence: Offices across multiple UK cities
Contact Information:
- Website: www.uhy-uk.com
- Facebook: www.facebook.com/uhyuk
- LinkedIn: www.linkedin.com/company/uhy-hacker-young
- Instagram: www.instagram.com/uhy_uk
- Address: Quadrant House, 4 Thomas More Square, London
- Phone: +44 20 7216 4600
PEM
Cambridge-based PEM has a dedicated international tax offering for companies and individuals. Its business tax specialists advise on overseas expansion, establishing international operations, cross-border transactions, transfer pricing, profit extraction and reporting requirements under UK and foreign rules.
The international practice also extends into employment tax, personal tax and VAT. This is useful where an overseas expansion affects several parts of the organisation at once, such as relocating employees while creating a new entity and dealing with cross-border VAT. PEM is part of Kreston Global and uses the network for support in other jurisdictions.
Key Facts:
- Ideal for: Businesses expanding internationally and individuals with UK and overseas tax obligations
- Core services: International business tax, employment tax, personal tax and VAT
- Business focus: Cross-border transactions, overseas structures and transfer pricing
- International network: Kreston Global
- Location: Cambridge
Contact Information:
- Website: www.pem.co.uk
- Email: [email protected]
- LinkedIn: www.linkedin.com/company/pem
- Instagram: www.instagram.com/pem_people
- Phone: 01223 728222
- Address: Salisbury House, Station Road, Cambridge, CB1 2LA
RSM UK
RSM’s international tax practice works with companies investing into the UK as well as UK businesses expanding abroad. Its services include international tax planning, transfer pricing, holding company strategy, global mobility and coordinated international compliance.
For inbound businesses, the firm can advise on branch or subsidiary choices, registrations, payroll considerations and transfer pricing. Its global compliance operation also covers corporate, employment and indirect tax requirements. RSM states that its tax specialists work across more than 120 jurisdictions, making the service particularly relevant where a group needs coordinated support in several countries.
Key Facts:
- Ideal for: Mid-sized and large businesses with multi-country operations
- Core services: International corporate tax, transfer pricing and global compliance
- Expansion support: Both inbound UK investment and outbound growth
- Additional capabilities: Global mobility and VAT compliance
- International reach: Tax specialists across more than 120 jurisdictions
Contact Information:
- Website: www.rsmuk.com
- LinkedIn: www.linkedin.com/company/rsm-uk
- Instagram: www.instagram.com/rsm.uk
- Address: 4th Floor, G1 5 George Square, Glasgow G2 1DY
- Phone: +44 (0)141 285 3900
BDO UK
BDO’s corporate international tax practice deals with businesses ranging from companies making an initial move overseas to multinational groups with established operations. Its work covers transfer pricing, withholding taxes, cross-border financing, international VAT and tax issues connected with mergers and acquisitions.
International mobility and employment taxes can also be incorporated into an assignment. For organisations that prefer central coordination, BDO provides a UK point of contact while drawing on its international network for local tax expertise in other jurisdictions.
Key Facts:
- Ideal for: Businesses with substantial or growing international operations
- Core services: Corporate international tax, transfer pricing and cross-border finance
- Additional services: International VAT, employment tax and mobility
- Transaction support: International tax due diligence and acquisition structuring
- International reach: BDO network operating across more than 160 countries
Contact Information:
- Website: www.bdo.co.uk
- E-mail: [email protected]
- LinkedIn: www.linkedin.com/company/bdo-llp
- Instagram: www.instagram.com/bdo_uk
- Address: 55 Baker Street, London, W1U 7EU, United Kingdom
- Phone: 020 7486 5888
KPMG UK
KPMG UK’s international and complex corporation tax team supports businesses investing across borders, extending an existing international footprint or reviewing tax risks in multinational structures.
Its cross-border services cover permanent establishment risk, controlled foreign company rules, tax residence, treaties and foreign jurisdiction requirements. KPMG also advises on cash repatriation, cross-border financing and withholding tax implications. This corporate focus makes the practice particularly suited to organisations where international tax is closely connected with financing, group structure and wider tax governance.
Key Facts:
- Ideal for: Large businesses and groups with complex international structures
- Core services: International corporation tax, cross-border investment and tax risk
- Specific areas: Permanent establishments, CFC rules, treaties and tax residence
- Financing support: Cash repatriation, debt financing and withholding tax
- UK location: Nationwide office network
Contact Information:
- Website: kpmg.com
- Facebook: www.facebook.com/KPMG
- Twitter: x.com/kpmguk
- LinkedIn: www.linkedin.com/company/kpmg-uk
- Address: 1, St Peter’s Square, Manchester M2 3AE, United Kingdom
- Phone: +44 (0)161 246 4000
Haines Watts
Haines Watts provides international tax planning for both companies and individuals. Corporate services include international ownership structures, profit repatriation, withholding taxes, double taxation relief and controlled foreign company matters.
Its personal international tax work covers individuals coming to or leaving the UK, while the firm’s international compliance service is designed for clients with obligations both domestically and abroad. Haines Watts also handles international tax investigations, giving clients access to support where cross-border arrangements or overseas tax matters lead to HMRC scrutiny.
Key Facts:
- Ideal for: Owner-managed businesses, international companies and private clients
- Core services: International tax planning and compliance
- Corporate focus: Withholding tax, profit repatriation, CFC matters and double taxation
- Individual focus: Tax matters connected with moving into or out of the UK
- Additional support: International tax investigations
Contact Information:
- Website: www.hwca.com
- E-mail: [email protected]
- Twitter: x.com/haineswatts
- LinkedIn: www.linkedin.com/company/haines-watts
- Address: Sophia House, 28 Cathedral Road, Cardiff, CF11 9LJ
- Phone: 02921 302 089
James Cowper Kreston
James Cowper Kreston works with UK businesses expanding overseas and international businesses establishing a UK presence. Its international business tax work includes reviewing double tax treaties, withholding taxes and transfer pricing strategies.
The wider international practice can also bring in indirect tax and global mobility specialists. This allows a business to consider corporate tax together with VAT and the tax implications of moving employees between countries. As a Kreston Global member, the firm can coordinate work with advisers in overseas markets when local tax input is needed.
Key Facts:
- Ideal for: Growing UK companies and overseas companies entering the UK
- Core services: International business tax, transfer pricing and treaty analysis
- Additional support: Global mobility and indirect tax
- Expansion focus: Overseas market entry and UK inbound investment
- International network: Kreston Global
Contact Information:
- Website: www.jamescowperkreston.co.uk
- E-mail: [email protected]
- Facebook: www.facebook.com/jamescowperkreston
- Twitter: x.com/JamesCowperk
- LinkedIn: www.linkedin.com/company/james-cowper-kreston
- Instagram: www.instagram.com/jamescowperkreston
- Address: 11th Floor, 30 Crown Place, London EC2A 4EB
- Phone: +44 (0)203 817 9350
PwC UK
PwC’s international tax and treasury practice is aimed primarily at companies operating across multiple jurisdictions. It combines international tax advice with areas such as transfer pricing, tax controversy, legal services and indirect taxation.
The work is particularly relevant to organisations dealing with international reporting requirements, statutory filings and tax strategy across a multinational group. Its scale also means the firm can address cross-border tax alongside broader treasury and corporate considerations where international operations involve numerous entities or markets.
Key Facts:
- Ideal for: Multinational businesses and groups with complex cross-border tax requirements
- Core services: International tax and treasury
- Related capabilities: Transfer pricing, indirect tax and tax controversy
- Cross-border focus: Multi-jurisdiction compliance and international tax strategy
- UK presence: National office network
Contact Information:
- Website: www.pwc.com
- Facebook: www.facebook.com/PwCUK
- LinkedIn: www.linkedin.com/company/pwc-uk
- Instagram: www.instagram.com/pwc_uk
- Address: One Chamberlain Square, Birmingham, B3 3AX
- Phone: +44 (0)121 265 5000
Lovewell Blake
Lovewell Blake provides international services to businesses exporting, importing, establishing UK operations or otherwise working across borders. Its business offering combines tax and accounting compliance with VAT advice, corporate structuring and support for overseas companies setting up UK subsidiaries.
The firm also advises individuals with international tax matters, including UK residence questions, overseas income and situations where tax obligations arise in more than one country. Lovewell Blake is a member of HLB International, which gives its UK teams access to advisers in overseas jurisdictions when international coordination is required.
Key Facts:
- Ideal for: SMEs, overseas businesses entering the UK and individuals with international affairs
- Core services: International tax, business compliance and cross-border VAT
- Inbound support: UK subsidiary establishment and tax compliance
- Individual support: Residence, overseas income and double taxation matters
- International network: HLB International
Contact Information:
- Website: www.lovewell-blake.co.uk
- Email: [email protected]
- Facebook: www.facebook.com/LovewellBlake
- Instagram: www.instagram.com/lovewellblakelb
- Twitter: x.com/LovewellBlake
- LinkedIn: www.linkedin.com/company/lovewell-blake-chartered-accountants
- Instagram: www.instagram.com/lovewellblakelb
- Phone: 01603 663300
- Address: Bankside 300, Peachman Way, Broadland Business Park, Norwich, NR7 0LB
Conclusion
Cross-border tax services in the UK vary considerably in scale and focus. Some firms concentrate heavily on multinational corporate structures, transfer pricing and international reporting, while others combine business tax with advice for individuals moving between countries, overseas investors or owner-managed companies expanding internationally.
The right fit depends on the jurisdictions involved and the work required. A company establishing its first overseas subsidiary may value practical structuring and ongoing compliance support, while a multinational group may need transfer pricing, Pillar Two, international financing and multi-country coordination. Individuals may instead need residence, treaty and double taxation advice. Comparing those capabilities against the actual cross-border situation is more useful than choosing a provider on size alone.