International Tax Compliance and Advisory
Inbound International Tax Compliance
Cross-border US tax compliance for foreign individuals and foreign-owned entities operating in the United States.
Foreign-owned US businesses and nonresident individuals face complex reporting requirements, including Form 5472, Form 1040-NR, Form 1120-F, and FIRPTA-related filings. We provide clearly scoped, technically precise compliance support designed to mitigate penalty exposure and ensure defensible filing positions.
Focus Areas:
Form 5472
Form 1040-NR
Form 1120-F
FIRPTA/ECI Analysis
Outbound International Tax Compliance
Cross-border US tax compliance for US persons with foreign entities, foreign investments, or international residency.
US citizens and residents with foreign corporations, partnerships, disregarded entities, or financial accounts face complex reporting obligations, including Forms 5471, 8858, 8865, 926, FBAR, and Form 8938. We provide clearly scoped compliance and advisory support designed to address classification issues, ownership analysis, Subpart F and GILTI considerations (as applicable), and related disclosure requirements.
Our approach emphasizes accurate reporting, defensible filing positions, and proactive identification of penalty exposure in multi-jurisdictional structures.
Focus Areas:
Form 5471
Form 8858
Form 8865
FBAR and Form 8938
Cross Border Structuring and Classification Analysis
Expat and Immigration Tax Compliance
US tax compliance for individuals navigating cross-border residency, immigration, and foreign income reporting
US citizens, green card holders, and foreign nationals relocating to or from the United States face complex and often overlapping tax reporting obligations. These include residency determinations, foreign income reporting, treaty considerations, and extensive foreign asset disclosures. We provide clearly scoped compliance support to ensure accurate filings and defensible positions across jurisdictions.
Our work focuses on proper classification, coordination of US and foreign tax systems, and mitigation of penalty exposure in fact-specific cross-border situations.
Focus Areas:
Foreign Earned Income Exclusion
Streamline Filings
Foreign Tax Credits
FATCA and FBAR
Dual Resident Returns
Immigration and First Year Filings
International Tax Consulting
Technical cross-border tax guidance for complex inbound, outbound, and expat matters
International tax issues often require analysis beyond return preparation. We provide focused advisory support on entity classification, residency determinations, treaty positions, cross-border structuring, and reporting risk exposure. Engagements are clearly scoped and grounded in the specific ownership, income, and jurisdictional facts involved.
Our advisory work is designed to support defensible filing positions and informed decision-making in penalty-driven compliance environments.
Focus Areas:
Entity Classification
Check-the-Box Analysis
Residency & Dual-Status
Treaty-Based Return Positions
ECI Analysis
Cross-Border Structuring
International Risk Assessments
Meet Your Tax Professional
Marcus Shimotsu
Marcus Shimotsu is a Certified Public Accountant specializing in U.S. international tax compliance and planning for foreign individuals and companies doing business in the United States. With extensive experience advising cross-border businesses, investors, and accounting firms worldwide, Marcus focuses on simplifying the complexities of U.S. reporting requirements—such as Forms 5471, 5472, 8865, 8858, and 3520—while developing strategies that align with each client’s global objectives.
Drawing on a background in corporate taxation and international structuring at Big 4 and large tax firms, Marcus provides tailored solutions that balance compliance with opportunity. His approach combines technical precision with practical insight, helping clients reduce exposure to costly penalties and navigate the intersection of U.S. and foreign tax regimes with confidence.
Marcus works with clients across the U.K., Asia, Europe, and beyond, offering a seamless advisory experience built on professionalism, transparency, and a deep understanding of international tax law.
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Contact us today, and let us show you how simple and efficient managing your taxes can be.