Designing a solid international tax structure: step-by-step framework

3 jurisdictions. How to design an efficient, defensible, audit-proof international structure. Complete six-step framework with regulations, criteria and profile examples.

A solid international tax structure crosses at least 3 jurisdictions (residency, operations, banking) and runs into the OECD's 15 BEPS actions, designed to stop artificial profit shifting.

Designing an international tax structure is not picking the most exotic country on the map, or copying the structure of the influencer of the day. It's a methodical exercise demanding personalized analysis, cross-cutting regulation and, above all, honesty about your real situation. At Exentax we've applied the same professional framework for years, and here we share it step by step.

From diagnosis to an executable international structure

Step 1: Real (not aspirational) diagnosis

Before designing anything, you must understand:

• Your real economic activity: what you sell, to whom, how you collect, your expenses, your margin, expected growth. This determines tax classification and regime. Activity-by-activity detail in <a href="/en/blog/llc-tax-by-activity-services-saas-and-trading">LLC taxation by activity</a>.
• Your real (not desired) tax residency: days of presence, centre of economic interests, family core. Tax residency is not chosen by declaration; it's determined by facts. Developed in <a href="/en/blog/international-tax-residency-with-a-us-llc">international tax residency and real mobility</a>.
• Your asset situation: what you have, where, in whose name. The asset diagnosis defines what to protect and what to declare (Form 720, 721 in Spain; LATAM equivalents).
• Your 5-year objective: grow, maintain, sell the business, retire. Each leads to different structures.

Without this diagnosis, any "design" is shooting blind.

Step 2: Define target tax residency

Three scenarios:

1. Maintain Spanish/LATAM residency: structure must be efficient with that residency. Most of our clients, where good planning adds the most value.
2. Move residency to a country with more efficient tax regime (Andorra, Portugal NHR/IFICI, Italy 100k regime, UAE, Paraguay, Costa Rica): requires real move, residency certificate, effective break with country of origin and time (minimum a full year of change).
3. You operate internationally with a real base outside your country of origin: each case needs documentary, banking and tax analysis.

Deciding this before design saves costly redesigns.

Step 3: Choose the right vehicle

There is no "best" vehicle. There is a suitable vehicle for each profile. Most common options:

• US Single-Member LLC Disregarded Entity: ideal for B2B professional services, low CFC risk, high operational efficiency. State comparison in <a href="/en/blog/new-mexico-wyoming-or-delaware-tax-and-banking">New Mexico vs Wyoming vs Delaware</a>.
• US Multi-Member LLC Partnership: when several partners without need for corporate taxation.
• LLC with check-the-box election as C-Corp: when corporate tax opacity is needed, generally for profit reinvestment or capital raising.
• Spanish operating S.L.: when activity is essentially Spanish and risk of simulation/hidden PE is high.
• Spanish holding + foreign subsidiary: for asset profiles with succession needs, multiple businesses or complex international operations.
• Estonian OÜ, Hong Kong Limited, Singapore Pte Ltd, BVI: specific vehicles with their own requirements and limitations. The Estonian OÜ is overhyped in social media; see <a href="/en/blog/estonian-company-vs-us-llc-22-tax-cfc-and-banking">why not to form a company in Estonia</a>.

The right choice depends on diagnosis × residency × activity × exit vision.

Step 4: Build substance

Substance distinguishes a defensible structure from paper. It comprises:

• Legal substance: formal documents (Articles, Operating Agreement, BOI Report, EIN, registered agent, real operational address). See <a href="/en/blog/llc-documents-keep-the-file-bankable-and-audit-ready">LLC documents</a>.
• Operational substance: clear account separation, real bookkeeping, customer contracts, invoices in LLC's name, tools and services contracted in LLC's name, marketing in LLC's name. See <a href="/en/blog/separate-personal-and-llc-finances-with-legal-shield">separating personal and LLC money</a>.
• Economic substance: revenues generated in LLC's name, deductible expenses imputed to LLC, working capital in LLC accounts. See <a href="/en/blog/llc-deductions-with-proof-and-tax-judgment">LLC deductible expenses</a>.
• Decisional substance: strategic and operational decisions made in LLC's name, ideally documented in minutes or memos.

Without substance, a structure falls at the first serious request.

Step 5: Design a coherent banking stack

Banking stack is the other half of substance. General recommendations:

• Primary account: Mercury or Relay (US), for operational solidity, FDIC sweep banking and low CRS footprint. See <a href="/en/blog/mercury-wise-and-revolut-kyc-freeze-prevention">how to open Mercury</a>.
• Multi-currency secondary: Wise Business or Revolut Business for EUR/GBP/EU operations, aware of their CRS profile. See <a href="/en/blog/wise-business-and-crs-for-us-llc-owners">Wise and CRS</a> and <a href="/en/blog/revolut-business-crs-and-us-llc-banking-perimeter">Revolut and CRS</a>.
• Payment gateways: Stripe, PayPal, compatible processors or DoDo Payments per model. See <a href="/en/blog/payment-stack-for-llc-stripe-hotmart-and-sequra">gateways comparison</a>.
• Treasury and investment: Slash or Mercury Treasury for operational liquidity; Interactive Brokers for longer-term investment.

Coherence: accounts and cards in LLC's name, collections and payments tied to real activity, no mixed personal use.

Step 6: Compliance and ongoing review

Compliance isn't an event, it's an annual process:

• US: <a href="/en/blog/irs-and-llc-ein-form-5472-and-filing-calendar">Form 5472</a> + pro-forma Form 1120 annually, BOI scope review under current <a href="https://www.fincen.gov" target="_blank" rel="noopener">FinCEN</a> rules, registered-agent renewal and state Annual Report if applicable. See Form 5472, <a href="/en/blog/anti-money-laundering-for-llc-bsa-kyc-ctr-and-sar">BOI scope today</a> and <a href="/en/blog/annual-llc-maintenance-irs-state-and-banking-control">annual LLC maintenance</a>.
• LATAM: annual return + foreign-income reporting regimes per country.
• Annual review: residency, substance, banking stack, new regulation (DAC7, DAC8, MiCA, DTT changes), modified thresholds.

Examples by profile

Profile 1: B2B freelance advisor resident in Spain, invoices €80,000-€150,000/year, no team.

Typical recommended structure: Single-Member LLC in New Mexico, Disregarded Entity, Relay or Slash as the operating layer when the profile fits, Wise Business for EUR clients, corporate cards only when they add real control, and bookkeeping in the LLC's name. Spanish classification: economic-activity income imputed to partner. Savings vs pure self-employed: significant.

Profile 2: Amazon Europe e-commerce, Spanish resident, €200,000-€500,000/year.

Recommended: LLC with substance + IOSS/OSS in EU MS of identification + customs advisory. Possibly EU subsidiary to minimize VAT friction if volume justifies. Mandatory DAC7 coordination.

Profile 3: International B2B SaaS, LATAM resident, €100,000 ARR.

LLC + Mercury + Stripe + Merchant of Record for international subscriptions. Local classification depends on country; partner remittance planning.

Profile 4: Professional trader with crypto and futures.

LLC without substance is high-risk (CFC). Analysis of residency change or structure with real substance. Possible subsidiary in jurisdiction with specific trading regime. Mandatory DAC8 compliance.

Framework in one image

Shortcuts that weaken an international structure

• Skipping step 1 and opening an LLC without diagnosis.
• Changing residency "on paper" without real move.
• Picking vehicle by trend, not fit.
• Designing without substance to "save time and money".
• Mixing personal and LLC finances.
• Not planning annual review.

To avoid them, see the full risks catalogue in <a href="/en/blog/international-tax-risks-cfc-banking-and-ownership">tax risks of bad international structuring</a>.

What matters before execution

A solid international tax structure is the result of a process, not a shortcut. Each framework step reinforces the next. Skipping one weakens all the others. The good news: well-designed, an international structure can substantially reduce your tax burden within the law, with a solid documentary footprint and no surprises.

Want us to design your structure step by step applying this framework to your case? book your strategic review and we'll start.

If something in this structure left you wanting more detail, <a href="/en/blog/us-llc-bank-accounts-fatca-crs-and-privacy">Do US bank accounts report to your home tax authority? The honest answer</a> dives into a neighbouring piece of the puzzle we usually keep for a separate write-up.

A structure is only solid when the legal, banking, tax and documentary layers agree. This guide gives the framework; the final answer depends on the client’s residence, activity, cash flow and risk profile.

Banking must follow the operating model

A serious tax structure first defines how money comes in, is held, is exchanged and is invested:

• Banking is designed after the structure, not before it. Residence, clients, revenue model, retained profits and reporting exposure decide which accounts make sense.
• Every account needs a role. Operating receipts, reserves, FX, card spend, broker funding and owner distributions should not be mixed without a written reason.
• The banking stack must support tax defensibility. If the account holder, provider entity, invoices and withdrawal policy tell different stories, the structure looks improvised.
• Exentax documents the why. A solid file records why each provider was selected, what it is used for and what evidence will be kept if compliance asks questions.

> <a href="/en/book">Review my case</a>

• Mercury: can help with USD collections, but it requires documentary discipline. Exentax reviews activity, invoices, payment provider, support account and narrative before depending on it.

• Payoneer operates through European entities (Payoneer Europe Ltd, Ireland) that are also in scope for CRS for clients resident in participating jurisdictions.

Design the structure from facts and documents

A strong international structure is designed before the first provider asks questions. Exentax reviews the entity, bank, payment layer, documents, tax calendar and residence position together, then tells the client where the LLC adds value and where another route is cleaner.

A solid structure starts from the member, not the LLC

A common mistake when designing an international structure is to

start from the entity. The right starting point is the member: their

tax residence, their personal balance sheet, the lifestyle and

mobility plans for the next two to five years, and the activities

the LLC will actually perform. Once that picture is honest and

written down, the entity choice almost designs itself.

Starting from the member also removes the temptation to over-engineer

with multi-layer holdings the activity does not need. A single

operational LLC, kept clean and well documented, beats most

"complex but elegant" diagrams in real-world reviews.

Three structures we have run with clients

A advisor in Spain with EU and US clients runs a single-member

LLC paired with a small Mercury + Wise stack. The income flows to

her annual personal declaration; the LLC's pro-forma 1120 + 5472

documents the related-party flows; no holding layer was needed.

Total annual maintenance: light.

A two-member team in Portugal and Germany runs an LLC together,

with allocation defined in the operating agreement. Each member

declares the proportional share at home; the LLC is the operational

shell, not a holding. The structure is portable and survives a

member relocation without redrawing the diagram.

A founder with a SaaS line and a separate advisory line runs two

LLC, one per business line. Each one has its own books, its own

bank stack and its own W-8 cycle. The separation simplifies sale

optionality later (one line could be sold without affecting the

other) and keeps reporting clean.

Mistakes to avoid in design

• Designing the structure to chase a tax outcome the member's

residence does not allow. The home country's effective place of

management rules will eventually win.

• Stacking holdings to "look corporate" when the activity is single-

person advisory. The complexity becomes its own risk surface.

• Forgetting that BOI applies to the LLC and to its beneficial

owners, regardless of how clean the home declaration is.

• Treating the operating agreement as boilerplate. It is the

foundational document that determines who signs, who decides and

how disputes are resolved.

Pre-design checklist

• Member tax residence confirmed and documented.
• Two-to-five-year mobility plan written down.
• Activity description: clients by country, expected revenue band.
• Bank stack pre-mapped (Mercury, Relay, Wise, Stripe roles).
• Annual compliance calendar (1120 + 5472, BOI, state, CRS where

applicable, home-country declaration).

We design every structure to be defensible in the only forum that

matters: the home tax administration of the member. Everything else

is downstream.