Tax Frameworks for Global Founders

Tax is the largest wealth transfer most founders will ever make. Not to investors, not to employees, not to vendors—to the government.

And yet most founders don't think seriously about tax until it's too late. They're heads-down building, focused on product-market fit, scaling teams, closing deals. Tax feels like something for accountants to figure out after the fact.

Then the exit happens. Or it's about to happen. And suddenly there's scrambling—asking friends who moved to Dubai, googling "Portugal NHR" at 2 am, wondering if things should have been structured differently five years ago.

The pattern is consistent: founders who think about tax early pay less than those who panic late. Sometimes the difference is seven figures.

This isn't a post about which country has the lowest rates. That information is freely available and usually misleading anyway. Instead, it provides a framework for thinking about tax—one that holds up regardless of which jurisdictions are in play and whether the rules change next year.

Because they will change. They always do.

But before you continue, just to be clear.

Mental Model: Tax as Cost of Jurisdiction

Here's the mindset shift that changes everything: stop thinking about tax as theft or punishment. Start thinking about it as a cost of doing business in a particular place—like rent, or salaries, or regulatory compliance.

This isn't about being naive or accepting whatever governments demand. It's about being clear-eyed. When renting office space in London versus Lisbon, there's a calculation about what each location offers for the price. The same logic applies to tax residency.

What do taxes pay for? In the UK: rule of law, contract enforcement, a stable currency, sophisticated banking infrastructure, and access to talent pools and deal flow. In a zero-tax jurisdiction, possibly lower costs but potentially worse infrastructure, thinner professional networks, and lifestyle trade-offs.

The question isn't "how do I pay zero?" It's "what's the right trade-off for my situation?"

A pattern that emerges frequently: a founder moves his family to a Gulf state specifically to avoid UK capital gains tax on an exit. The tax savings are substantial—potentially in the seven-figure range. But the reality doesn't match expectations—social isolation, concerns about school quality, distance from ageing parents. Within 18 months of the sale's completion, the family is back in London, having spent much of the "savings" on temporary housing and international schools.

The math on tax can't be separated from the math on life.

Framework for Evaluating Jurisdictions

Five factors determine whether a jurisdiction makes sense. Rate is only one of them, and rarely the most important.

Effective rate vs. headline rate. Every country advertises a headline rate, but what founders actually pay is often different. The UK's headline capital gains rate is 24%, but Business Asset Disposal Relief can reduce that to 14% on the first £1 million of qualifying gains. The US federal rate is 20%, but state taxes can push California founders above 33%—or QSBS exclusions can reduce the federal portion to zero on up to $15 million. Always calculate the effective rate for the specific situation.

Stability and predictability. Tax systems change, but some change more than others. The UK reduced the BADR lifetime limit from £10 million to £1 million in March 2020, then raised CGT rates in the 2024 Autumn Budget. Meanwhile, Singapore's territorial system has remained largely consistent for decades. When planning a multi-year transition or exit, predictability matters. A 15% rate that stays constant is often better than a 10% rate that could rise to 20% by the time of sale.

Complexity and compliance burden. Some jurisdictions are low-tax but high-hassle. Free zone structures in the Gulf require ongoing substance requirements. US citizenship comes with worldwide taxation and FATCA reporting regardless of where you live. The administrative burden of maintaining a structure can eat into apparent savings—and create risks if something goes wrong.

Enforcement culture. This is harder to quantify, but real. Some tax authorities are aggressive in challenging arrangements; others take a more pragmatic approach. The UK's HMRC has become significantly more focused on challenging tax residency claims in recent years. The IRS has essentially unlimited reach and resources when it pursues cases. Understanding how a tax authority actually behaves—not just what the rules say on paper—matters.

Professional infrastructure. Advisors who understand both the current and target jurisdictions are essential. For common corridors (UK-US, UK-Singapore, UK-UAE), this is straightforward. For unusual combinations, finding competent cross-border advice can be expensive and time-consuming. Factor this into planning.

Key Concepts That Differ Globally

Before looking at specific jurisdictions, several concepts work very differently across locations.

Tax residency definitions. In the UK, the Statutory Residence Test considers multiple factors—days spent in the country, ties to the UK, and where work is performed. Spend more than 183 days, and residency is almost certain. But even 90 days can trigger residency if there are enough ties. The US is simpler in some ways—green card holders and citizens are taxed on worldwide income regardless of where they live. UAE uses 183 days in a rolling twelve-month period, with a 90-day alternative for those with permanent residence and sufficient substance.

Capital gains treatment. The variance is enormous. The US taxes long-term gains at 0%, 15%, or 20% at the federal level (plus state taxes and a potential 3.8% Net Investment Income Tax). The UK taxes gains at 18% or 24%, with some reliefs available. Singapore has no capital gains tax. Hong Kong—same. UAE—same. But "no capital gains tax" doesn't mean "no tax"—there may still be taxes in the home country or where the assets are located.

Territorial vs. worldwide systems. The US and UK tax residents on worldwide income. Singapore and Hong Kong use territorial systems—they only tax income sourced within their borders (with some exceptions for remitted foreign income). This distinction fundamentally changes planning options. A Singapore resident can earn foreign investment income essentially tax-free, provided it stays offshore. A US citizen pays tax on that same income regardless of where they bank.

Exit taxes. Some countries impose a tax when residents leave—essentially a deemed disposal of assets at departure. The US has a brutal exit tax for "covered expatriates" (those with net worth over $2 million or average annual tax liability over $206,000). Assets are taxed as if sold the day before renunciation, with only an $890,000 exclusion (2025 figure). The UK currently has no exit tax, though there's recurring speculation about introducing one. Countries such as Germany, Australia, and Canada have some form of exit taxation.

Controlled Foreign Corporation (CFC) rules. Many countries have rules that attribute income from foreign companies back to domestic shareholders. A UK resident who sets up a company in Singapore may find the UK's CFC rules tax that company's profits as if earned personally, depending on the company's activities and level of control. These rules exist specifically to prevent the "just incorporate offshore" strategy from working for residents of high-tax countries.

How the US Taxes Founders

American founders face a unique challenge: the US taxes citizens and green card holders on worldwide income, regardless of residence. Moving to Dubai doesn't help if you're American. US taxes are filed for life, or until renunciation.

The good news is that the US has some of the most founder-friendly provisions available—if structured correctly from the start.

QSBS (Qualified Small Business Stock). Under IRC Section 1202, founders can exclude up to $15 million of federal capital gains tax on the sale of qualifying small business stock. Following the One Big Beautiful Bill Act of July 2025, the rules became more favourable: the asset threshold increased from $50 million to $75 million, the exclusion cap rose from $10 million to $15 million, and shorter holding periods now qualify for partial exclusions (50% after three years, 75% after four years, 100% after five years for stock issued after July 4, 2025).

To qualify: the company must be a US C-corporation, must have had gross assets under the threshold when stock was issued, must use at least 80% of assets in an active qualified business, and can't be in certain excluded service industries (law, accounting, health, financial services, and similar).

For founders of technology companies, QSBS can be transformative. A founder selling a $30 million stake with minimal basis could save $3 million or more in federal taxes. Combined with trust stacking strategies—where QSBS is gifted to non-grantor trusts for family members, each with their own exclusion—the potential savings multiply. The Northern Trust QSBS guide provides a detailed analysis of these strategies.

The catch: not all states conform to federal QSBS treatment. California doesn't recognise it at all, meaning a California-resident founder still pays 13.3% state capital gains tax even on federally excluded gains. According to the Tax Foundation, states like Alabama, Mississippi, and Pennsylvania also don't conform. Some founders relocate to no-income-tax states before exits specifically to capture the full benefit.

State tax variation. US tax planning is really fifty-one different calculations. A founder in Wyoming, Texas, or Florida faces zero state income tax. A founder in California or New York faces rates above 10%. On a $20 million exit, that's the difference between paying nothing and paying $2 million-plus at the state level alone.

Establishing residency in a new state requires a genuine relocation—changing driver's licenses, voter registrations, banking information, and actually living there. Tax authorities are increasingly aggressive in challenging "paper moves" in which founders claim Texas residency while spending most of their time in California.

Exit tax for renunciation. American founders considering giving up citizenship face the exit tax under IRC Section 877A. If classified as a "covered expatriate"—net worth over $2 million, average annual tax liability over $206,000 over the prior five years, or failure to certify five years of tax compliance—there's a deemed sale of all worldwide assets the day before expatriation. Any gains above the $890,000 exclusion (2025 figure, per IRS guidance) are taxed at capital gains rates.

This means US citizenship itself has a "price tag" for wealthy individuals who want out. A founder with $30 million in unrealised gains faces a potential tax bill approaching $6 million just to leave. This is why thoughtful founders think about citizenship as an asset class—and why renouncing before becoming wealthy is a very different calculation than renouncing after.

How the UK Taxes Founders

The UK uses a residence-based system with some nuances around domicile. The rules changed significantly in April 2025 with the abolition of the non-dom remittance basis.

Capital Gains Tax. UK CGT rates sit at 18% for basic-rate taxpayers and 24% for higher-rate taxpayers on most assets (with higher rates on residential property). The annual exempt amount was slashed to £3,000 for 2024/25—effectively negligible for founders with serious gains. Current rates are published on GOV.UK.

Business Asset Disposal Relief. BADR (formerly Entrepreneurs' Relief) provides a reduced rate on qualifying business disposals. The rate was 10% until April 2025, rose to 14% from April 2025, and will increase to 18% from April 2026. The lifetime limit remains at £1 million of qualifying gains.

To qualify for BADR on shares, the seller must have been an employee or officer of the company, have owned at least 5% of the company's ordinary shares, and have held voting rights for at least two years before the disposal. Enterprise Management Incentive (EMI) shares have more relaxed conditions—the 5% ownership requirement doesn't apply if the option was granted at least two years before disposal.

The maths on BADR has changed dramatically. Before March 2020, founders could shield £10 million at 10%—a tax cost of £1 million. Today, £1 million can be shielded at 14% (rising to 18%)—tax cost of £140,000-£180,000. Everything beyond the first million faces the full 24% rate. The GOV.UK technical note details the 2020 changes.

Abolition of the non-dom regime. The traditional remittance basis—allowing UK residents with foreign domicile to keep offshore income and gains untaxed, provided they didn't bring them into the UK—ended in April 2025. It was replaced by the Foreign Income and Gains (FIG) regime, which provides 100% relief on foreign income during the first four years of UK residence, but only for those who hadn't been UK resident in any of the prior ten years.

For existing non-doms, transitional reliefs apply—including the Temporary Repatriation Facility (TRF), which allows bringing pre-April 2025 foreign income into the UK at a reduced rate (12% in 2025-27, rising to 15% in 2027-28). Saffery's analysis provides detailed coverage of the transitional arrangements.

No exit tax—yet. The UK currently doesn't impose an exit tax on departing residents. There's recurring speculation about introducing one, particularly following the non-dom changes. The November 2025 reports suggested a 20% "settling up charge" was under consideration, though it wasn't implemented in the Autumn Budget.

What does exist is the "temporary non-residence" rule: leaving the UK, selling assets, and returning within five years means taxation as if the departure never happened. This prevents the obvious strategy of becoming non-resident briefly, selling, then coming back.

How Singapore and Hong Kong Tax

These two Asian financial centres share a key feature: territorial taxation and no capital gains tax.

Singapore's system. Singapore taxes income sourced within its borders, as well as foreign-sourced income remitted to Singapore (subject to exemptions). There is no tax on capital gains. Selling shares in a foreign company as a Singapore resident typically means paying nothing in Singapore—provided the gain isn't recharacterised as trading income.

According to PWC's Singapore tax summary, the headline corporate tax rate is 17%, with an exemption for the first SGD 200,000 of chargeable income for qualifying new companies. Foreign-source dividends, branch profits, and service income can be exempt from tax when received in Singapore if they've been taxed abroad at 15% or higher.

Singapore's personal income tax rates are progressive, from 0% to 24% on income above SGD 1 million. This still compares favourably to high-tax jurisdictions, particularly for investment income.

The practical implication: a Singapore-resident founder selling shares in a company incorporated outside Singapore likely pays zero tax on the gain. This is genuinely powerful for internationally structured businesses.

However, Singapore isn't free. The cost of living is high. Immigration is selective—the Global Investor Programme requires at least SGD 10 million invested in a new or expanding business, SGD 25 million in a fund investing in Singaporean businesses, or the establishment of a family office with at least SGD 200 million (c. $150M) in assets. Residency doesn't come easily.

Hong Kong. Similar in structure to Singapore—territorial taxation, no capital gains tax. Corporate tax is 8.25% on the first HKD 2 million of profits, 16.5% thereafter. Personal income tax (salaries tax) tops out at 15%.

Hong Kong has faced political uncertainty in recent years, leading some to favour Singapore. But for pure tax efficiency on exit gains, both jurisdictions deliver similar results.

Substance requirements matter. Neither Singapore nor Hong Kong will shelter anyone if the residence claim lacks substance. Genuine presence is required—home, bank accounts, social ties, business activities. Tax authorities are increasingly sophisticated about identifying "flag of convenience" residencies. Don't assume Singapore residency when spending most of the time in London.

How the UAE Taxes

The UAE was long a true zero-tax jurisdiction. That's changing.

Personal income tax. Still zero. There is no personal income tax in the UAE. Capital gains for individuals—zero. Inheritance tax—zero. This remains the headline draw for wealth preservation.

Corporate tax. The UAE introduced a 9% federal corporate tax in June 2023, applying to business profits exceeding AED 375,000 (roughly $102,000). The UAE Ministry of Finance provides official guidance. Free zone companies can maintain 0% rates on qualifying income if they meet substance requirements and earn income from prescribed activities (typically intra-free zone transactions and exports).

From January 2025, the UAE also implemented a Domestic Minimum Top-Up Tax (DMTT) under OECD Pillar Two, applying a 15% minimum rate to large multinationals with global revenues exceeding EUR 750 million.

Residency and substance. UAE tax residency requires 183 days of presence in a rolling twelve-month period, or 90 days with a UAE residence permit and substance requirements (permanent accommodation, employment, or business presence).

The UAE issues Tax Residency Certificates (TRCs) that are increasingly important for claiming treaty benefits. But getting a TRC requires demonstrating genuine substance—physical presence, accommodation, and often a business license.

What residents actually get. Zero personal tax is real. But lifestyle factors matter: intense summer heat (40°C+ for months), social environment that may not suit everyone, distance from European or American networks, and questions about long-term political stability that each person assesses differently.

A number of founders have moved to Dubai, claimed tax residency, and then spent minimal time there—working primarily from London or other locations. Tax authorities are increasingly challenging these arrangements. The "fly in, fly out" residency that some advisors sold in the 2010s is higher risk today.

Tax Triangle: Residence, Source, and Citizenship

Here's a framework that clarifies most cross-border tax questions.

Every piece of income or gain has three potential taxing jurisdictions:

1. Residence—where the individual lives (for individuals) or where the company is managed and controlled (for corporations)
2. Source—where the income is generated or where the assets are located
3. Citizenship—for US citizens and green card holders, this adds a third always-present taxing jurisdiction

Most countries tax residents on worldwide income (residence-based). Some also tax non-residents on income sourced within their borders (source-based). Only the US systematically taxes based on citizenship.

Tax treaties exist to prevent double taxation when multiple jurisdictions have claims. But they don't always prevent all taxation—they typically allocate taxing rights and provide credits or exemptions.

Consider a UK citizen who relocates to Singapore, sells shares in a Delaware corporation, and receives the proceeds into a Swiss bank account:

• UK: No longer taxing (assuming non-residence for more than five years and genuine departure)
• Singapore: No capital gains tax on foreign shares
• US: No tax (not a US person, and share sales by foreign persons in foreign companies aren't US-source)
• Delaware: Not separately relevant—state taxes don't reach non-US persons on corporate share sales

The answer: likely zero tax. But change any element—make the seller a US citizen, have them return to the UK within five years, structure as an asset rather than a share sale—and the answer changes entirely.

This is why cross-border tax planning is complex. It's not about finding the lowest rate; it's about understanding how multiple overlapping systems interact.

Exit Tax Considerations

Exit taxes deserve special attention because they constrain options after wealth has accumulated.

Countries with meaningful exit taxes:

• United States: The most comprehensive. Covered expatriates face deemed disposal of worldwide assets, taxed at capital gains rates on amounts exceeding $890,000. See IRS Form 8854 instructions.
• Germany: Imposes an exit tax when residents leave and hold at least 1% of a German corporation. Tax can be deferred within the EU/EEA.
• Australia: Treats departure as a deemed disposal of most assets, though "taxable Australian property" (like real estate) remains taxable to non-residents.
• Canada: "Departure tax" treats emigration as deemed disposal of most property at fair market value.
• France: Exit tax on unrealised gains for long-term residents, though deferrals are available and the tax can be extinguished if assets are held for specified periods.

Countries without exit taxes:

• UK: Currently, no exit tax (the "temporary non-residence" rule isn't quite the same—it taxes gains realised during non-residence if return happens within five years)
• Singapore: No exit tax
• UAE: No exit tax

The practical implication: for US citizens with significant unrealised gains, the cost of exiting the US tax system is substantial. Plan for it early or accept being locked in.

For UK residents contemplating relocation, the window is currently open—but that could change. Any serious planning should consider the possibility that exit taxes arrive in the UK within the next decade.

Pre-Liquidity Decisions

The best tax planning happens before wealth accumulates. By the time a $50 million exit is in sight, many options have closed.

Entity structure. A US C-corporation can qualify for QSBS; an LLC taxed as a partnership cannot. Converting later is possible, but may reset holding periods or trigger current taxation. If QSBS is relevant, structure from the start. The Carta QSBS guide explains the requirements in detail.

Holding period. QSBS requires five years (or three to five years for stock issued after July 2025). BADR requires two years of ownership and employment. Three years into building a company without thinking about this? Start now.

Residence and domicile. UK domicile status historically mattered for inheritance tax and the remittance basis. While the remittance basis is gone, domicile still affects IHT. Establishing a non-UK domicile after the fact is difficult; maintaining it requires ongoing attention.

Gift and trust planning. Moving shares into trusts for family members before dramatic appreciation can multiply QSBS exclusions and shift future growth out of an estate. This must happen early—transferring appreciated stock triggers recognition of current gain in most jurisdictions. For deeper analysis, see Pre-Exit Wealth Planning.

State and country residence. The cheapest time to move is before gains exist. Relocating from California to Texas after a company is worth $100 million invites intense scrutiny from California's Franchise Tax Board. Doing it three years earlier, while still building, is a normal life choice.

None of this is advice to take aggressive positions. It's recognising that timing matters—decisions made early are more defensible and more valuable than scrambling at the last minute.

Common Mistakes

Certain errors recur among founders navigating tax planning:

Waiting too long. Tax planning that starts six months before an expected exit has limited options. QSBS needs five years. BADR needs two. Relocation needs to be established, lived, and documented. Start earlier than seems necessary.

Optimising for rate alone. Tax savings mean nothing when paired with misery, family unhappiness, or the inability to access the opportunities and networks needed for the next venture. The math on tax can't be separated from the math on life.

Underestimating complexity. International structures create ongoing compliance obligations. Advisors in multiple jurisdictions, multiplied filing requirements, and expensive mistakes. Simple structures that work reliably beat complex structures that require constant attention.

Taking advice from the wrong people. A mate who moved to Portugal isn't a tax advisor. The person selling Dubai residency has an incentive to close deals. Even accountants often lack cross-border expertise. Find advisors who specialise in the specific corridor—UK-Singapore, US-UAE, whatever applies—and who can coordinate across jurisdictions.

Aggressive schemes. Every few years, a new "tax planning strategy" makes the rounds—some complex structure that promises to eliminate tax through clever arrangements. Many get challenged by tax authorities and fail. The ones that survive often require ongoing compliance that founders neglect. For most founders, straightforward planning in favourable jurisdictions beats elaborate schemes.

Finding the Right Advisors

Cross-border tax is a specialist territory. Advisors who understand both the current and target jurisdictions and, ideally, have worked with founders in similar situations are essential.

What to look for:

• Specific experience with the relevant corridor (e.g., UK-to-Singapore, US-to-UAE)
• Willingness to coordinate with advisors in other jurisdictions rather than trying to handle everything themselves
• Clear explanations of risks, not just potential savings
• Flat or fixed fees for defined scope (avoid advisors who bill by the hour for open-ended "planning")
• References from other founders who've done similar moves

Red flags:

• Advisors who promise specific outcomes without understanding the situation
• Anyone suggesting structures that seem too good to be true
• Pressure to act quickly without time to consider options
• Unwillingness to put advice in writing
• Lack of experience with the specific situation (wealthy individuals generally, rather than founder exits specifically)

Tax advice is worth paying for. A good advisor on a $20 million exit might cost £20,000-50,000 and save multiples of that. The mistake is treating it as an expense to minimise rather than an investment that compounds.

Here is the deep dive on how to Build Your Advisory Team.

Questions to Ask

Before engaging in any serious tax planning, work through these questions:

On the situation:

• What's the realistic timeline to liquidity? (18 months, 3 years, 5+ years?)
• What's the likely size of the exit? (Range matters—planning for $10 million differs from planning for $100 million)
• Where is the actual desire to live? Where does the family want to be?
• How much time can be committed to maintaining any new structures or residence claims?
• What other income or assets affect the picture?

On the options:

• What's the effective tax rate doing nothing? (Calculate properly—not headlines)
• What would each alternative cost in tax terms and in life terms?
• What's the ongoing compliance burden of each option?
• What risks exist—both tax risk and life risk?
• How would each option interact with other plans (family, next venture, philanthropy)?

On timing:

• What decisions need to be made now vs. later?
• What options close with waiting?
• Is there a natural decision point (funding round, acquisition interest) that creates urgency?

Framework for Decision-Making

Here's an approach for thinking through this systematically:

Step 1: Understand current position. Calculate what would be owed under current rules, current residence, doing nothing special. This is the baseline.

Step 2: Identify realistic alternatives. What jurisdictions could genuinely work as a home? What structures are worth maintaining?

Step 3: Calculate the delta. What's the actual tax difference between baseline and alternatives? Be honest about effective rates and compliance costs.

Step 4: Factor in non-tax costs. Moving costs, lifestyle changes, family impact, advisory fees, opportunity costs of time spent on structures.

Step 5: Assess risk. What's the probability that each strategy fails or gets challenged? What's the risk tolerance?

Step 6: Decide—but reversibly where possible. Some decisions are one-way (renouncing citizenship). Others are adjustable (residence can often change again). Prefer flexibility unless the benefit of commitment is substantial.

The goal isn't to minimise tax at any cost. It's to find the outcome that best serves overall interests—financial, personal, and family. Sometimes that means paying more tax than technically necessary because the alternatives aren't worth it.

For a deeper analysis of jurisdiction selection, see the Family Office Location Playbook. For entity structuring considerations, see Structure — The Foundation.

I write when there’s something worth sharing — playbooks, signals, and patterns I’m seeing among founders building, exiting, and managing real capital.
If that’s useful, you can subscribe here.