If you are planning a move to the UK you need to understand what the UK’s new taxation rules mean for tax on your worldwide income.

In April 2025, the UK brought in major changes that affect how expats living in the UK are taxed. Whether you are moving for a couple of years or planning a permanent shift, it’s important to know how the rules work so you don’t get any unexpected surprises.

Becoming A UK Tax Resident

The UK automatic residency tests include:

• Residing in the UK for 183 days or more in the tax year.
• Spending at least one day of the tax year in the UK and working full-time in the UK for a period of 365 days.
• If your home was in the UK for 91 days or more in a row and you visit or stay in the UK for at least 30 days of the tax year.

If you do not meet the residency tests under any of the automatic tests you may still be a UK resident if you meet other conditions, such as sufficient ties and day-count thresholds.

New UK Residents

Once you are a UK resident you are generally taxed on your worldwide income.

Historically new UK residents were eligible for the “non-dom” rules. These rules allowed foreign income to be excluded from UK taxation when it is not remitted into the UK and meant that expats who were “non domiciled” individuals could return to their home country without any ongoing UK tax considerations (other than income relating to assets remaining in the UK).  

From April 2025 all UK residents are taxed on their worldwide income, regardless of their domicile.

UK Taxes On Worldwide Income

Under the new tax rules expats who are UK residents will generally:

• Pay UK taxes on their worldwide income, regardless of whether the money is brought into the UK.
• Pay capital gains tax on worldwide assets.
• Be subject to inheritance tax rules. Note that inheritance taxes may continue to apply even after departing the UK for individuals who reside in the UK for ten years or more.

Four Year Exemption

New arrivals to the UK (who have not been UK tax residents within the previous ten consecutive years) will receive 100% relief on foreign income and gains for the first four years of their UK residency.

This means you can live in the UK for up to four years before being taxed on your worldwide income or avoid the double taxation of worldwide income if you only live in the UK for less than four years.

Conclusion

Moving to the UK has significant tax implications for expats. Key issues revolve around when you commence UK residency. Proper planning before departure can minimise double taxation, optimise use of tax concessions and exemptions, and ensure you remain compliant in the UK and your home country. 

When you scale into a new market, nothing drains momentum faster than paying tax on the same profit in two places. The good news: Singapore’s pro-business tax framework and extensive network of double tax treaties make it straightforward—if you set things up correctly from day one.

What “Double Taxation” Really Means (In Plain English)

Double taxation happens when two jurisdictions both claim the right to tax the same income. For example, profits made by your new Singapore entity might also be taxed where your parent company is based. 

You may face this situation when your Singapore company meets the definition for corporate tax residency in two jurisdictions. For example, Australia takes a wide view of control and management, which means actions as simple as approving payments from Australia on a Singapore online banking platform may result in the Australian Tax Office concluding that the company’s tax residency is in Australia. 

Relief is available, but only if you structure and document your expansion with care.

Eight Practical Ways To Keep More Of Your Profit

1. Pick The Right Footprint – If you create a meaningful on-the-ground presence overseas (think office, team, or agent), you will be in a better position to argue that the Singapore company operates as an independent entity. Map your commercial plan, operating within your budget and growth phase of the Singapore company.  
2. Leverage Singapore’s Treaty Network – Singapore has an extensive set of Avoidance of Double Taxation Agreements (DTAs) that determine which country taxes which income and can reduce withholding taxes on cross-border payments. To access treaty benefits, you’ll usually need a Singapore Certificate of Residence—so plan to meet the residency requirements.
3. Be Clearly A “Singapore-Resident” – Treaty access typically requires that management and control are exercised in Singapore. In practice: board meetings held here, key decisions documented here, local directors who are genuinely involved, Singapore banking and records, and real operational substance.
4. Plan How Money Moves – Think through cash flows before you launch: dividends, service fees, interest, and royalties can each be taxed differently. In Singapore, dividends are generally not subject to withholding tax; other payments (such as royalties or loan interest) may be—unless a DTA reduces the rate. Model your routes so profits arrive efficiently.
5. Use Singapore’s Foreign Tax Reliefs – If your Singapore company is taxed abroad on the same income, relief may be available via tax credits or (for qualifying foreign-sourced dividends) exemption—subject to conditions. 

The Takeaway: Don’t leave credits unclaimed because documentation was an afterthought.

6. Price Intercompany Transactions At Arm’s Length – Whether it’s goods, services, IP, or financing, align pricing with real functions, assets, and risks. Maintain contemporaneous transfer-pricing documentation. It’s your best defence against audits in both countries.
7. Build Substance That Matches Your Story – Regulators look for people, processes, and decision-making to be based where profits are booked. Hire key roles in Singapore, empower them, and capture that governance trail in minutes and policies. Be ready to demonstrate that the team in Singapore operates as a standalone entity to HQ. This means control will lie only in Singapore, and reduces the risk of the tax authorities in the HQ jurisdiction claiming that your Singapore company meets its corporate residency definition.
8. Get Formal Advice And Get Your Paperwork Right – Seek guidance from qualified tax advisors in Singapore and your home jurisdiction.  Document DTA positions, residency evidence, and payment flows into a simple compliance calendar (treaty forms, COR renewals, filings). Clean execution prevents costly delays and withheld cash.

A Forward View 

As tax rules evolve globally, authorities are coordinating more closely and scrutinizing cross-border profit allocation. The winners will be companies that treat tax as part of their go-to-market design—not a year-end fix.