GMTS is a global mobility and international expansion advisory firm supporting companies and individuals worldwide with their cross-border tax, immigration and global workforce needs.

We provide independent, pragmatic advisory services across all stages of international expansion and expatriate assignment lifecycles, helping clients manage complexity, reduce risk and improve tax efficiency.

Our approach is grounded in independence, technical excellence and practical execution. By combining specialist expertise with a collaborative mindset, we help organisations and individuals navigate cross-border complexity with confidence.

Our Advisory Services

We currently provide advisory support in the following areas:

Global Mobility & Assignment Structuring

Assignment structuring across multiple jurisdictions, including:

• Expatriate tax and policy documentation (e.g. T&E policies, assignment letters)

• Cost of living differentials analysis

• Assignment cost projection and forecasting

• (Re)design and (re)implementation of global mobility and expansion policies

• Entity set-up and immigration advisory support

International Tax Planning & Analysis

We advise on international mobility and global expansion strategies and identify opportunities for tax efficiencies and special tax regimes, including:

• • The 30% ruling (Netherlands)

  • Beckham Law (Spain)

  • Detached Duty Relief (DDR), Statutory Residence Test (SRT) and Foreign Income & Gains (FIG) regimes (UK)

  • Other country-specific expatriate tax regimes

• Supporting clients in minimising total tax and social security costs in a fully compliant manner

International Expansion & Vendor Coordination

At relevant stages of the assignment lifecycle or company secondment programmes, we work closely with third-party service providers selected by our clients, including:

• Relocation providers

• External tax advisors

• Payroll providers in home and host jurisdictions

We also oversee, on behalf of our clients, coordination between HR, Corporate Tax, Corporate Governance and Legal functions, ensuring global mobility matters are managed collaboratively and efficiently.

Tax Compliance & Payroll Advisory

We assist with a broad range of compliance and operational matters, including:

• Tax compliance obligations such as:

  • Short Term Business Visitors (STBV)

  • Shadow payroll and Modified PAYE schemes

  • Fringe benefits reporting

  • Individual tax returns and tax payments

• Social security treaty analysis and implementation of savings opportunities

• Payroll consulting, including:

  • Home and host country payroll requirements

  • Expense reimbursements

  • Special wage tax provisions

Entity Set-Up & Cross-Border Advisory

We support clients in selecting the most appropriate entity structure for their international expansion, such as:

• Representative offices

• Branches

• Non-Resident Payroll (NRP) set-ups

• Subsidiaries

• Employer of Record (EOR) / Professional Employer Organisation (PEO) solutions

Our advice takes a 360-degree perspective, considering:

• Immigration (visa and work permit sponsorship)

• Corporate tax implications and Permanent Establishment (PE) risks

• HR and employment law considerations

• Posted Worker Rules and related regulatory requirements

• Tax and social security optimisation strategies

All to provide clients with confidence that no critical issue has been overlooked in their international expansion or mobility arrangements.

Ready to simplify your international expansion or cross-border issues?