Financial Planning in Japan: A Guide for British Expats and International Investors

Japan consistently ranks among the world's most desirable destinations for internationally mobile professionals: low crime, world-class infrastructure, exceptional food culture, and a highly efficient urban environment. Yet for British nationals and other Western expats, Japan also presents one of the most technically demanding financial planning environments they will encounter. The tax system is sophisticated, the rules governing foreign financial products are strict, and the cost of professional services in English is high. This guide sets out the key financial planning considerations for British nationals living, working, or investing in Japan as of 2026.

Tax Residency in Japan

Japan's tax residency rules centre on a concept of domicile and physical presence. As a general rule, an individual who resides in Japan for one year or more becomes a tax resident. However, Japan distinguishes between two categories of tax resident, and that distinction is financially significant.

Non-permanent residents are those who have not had a domicile in Japan — that is, who do not regard Japan as their permanent home — and who have been resident in Japan for a total of five years or fewer in the preceding ten years. Non-permanent residents are taxed in Japan on:

• Japan-source income (all of it), and
• Foreign-source income only to the extent it is remitted into Japan.

Foreign income that is earned and retained offshore — for example, dividends credited to a UK or offshore bank account that remain there — is not subject to Japanese tax during this period.

Permanent residents for tax purposes are individuals who have been resident in Japan for more than five years in any ten-year period. At that point, Japan taxes worldwide income at Japanese rates, regardless of where it is earned or held. The top combined rate — national income tax at 45% plus local resident tax at 10% plus a 2.1% solidarity surtax on income tax — can reach approximately 55% for high earners. This is among the highest effective rates in the developed world.

The five-year window is therefore a genuine planning opportunity. Professionals on fixed-term assignments, those on secondment, or those who choose to limit their Japanese stay to under five years can structure their affairs to keep offshore income outside the Japanese tax net entirely during that period.

UK Pensions in Japan

The UK-Japan Double Taxation Treaty allocates taxing rights on pension income to the country of residence — that is, Japan. For a British national resident in Japan, UK pension payments (whether from a personal pension, employer scheme, or annuity) are liable to Japanese tax rather than UK tax.

In practice, this means:

• You should apply to HMRC for an NT (nil tax) code so that your UK pension provider pays income gross, without UK tax deducted.
• Japanese tax will then apply based on your residency status: as a non-permanent resident, pension income remitted to Japan is taxable; income retained in a UK account is not.
• Once you become a permanent resident for Japanese tax purposes, all pension income is taxable in Japan whether remitted or not.

The UK State Pension is not frozen for Japanese residents (unlike, for example, Australia or Canada), and the triple lock uprating continues to apply. Given Japan's top tax rates, however, the net value of pension income received in Japan after five years of residency requires careful modelling.

QROPS (Qualifying Recognised Overseas Pension Schemes) have been marketed in certain Asian jurisdictions. There are currently no Japanese-based QROPS on the HMRC recognised list, and transferring a UK pension to a scheme in another country while resident in Japan requires careful analysis of both UK and Japanese tax treatment before any decision is made.

The Japanese Tax System in Detail

For British nationals accustomed to the relative simplicity of UK self-assessment, Japanese tax administration can be a considerable adjustment:

• National income tax is levied at progressive rates ranging from 5% on income up to approximately JPY 1.95 million to 45% on income exceeding approximately JPY 40 million. Rates are as of the 2026 fiscal year; thresholds are set in JPY and the GBP equivalent will vary with exchange rates.
• Resident tax (住民税, jūminzei) is levied by prefectural and municipal governments at a flat combined rate of approximately 10% on taxable income, lagged by one year behind national tax.
• Solidarity surtax (fukko tokubetsu shotokuzei) — a 2.1% surcharge on national income tax liability — was introduced after the 2011 earthquake and remains in force through 2037.

Tax returns are filed annually in March for the preceding calendar year. Engaging a qualified Japanese tax accountant (zeirishi) who works in English is strongly recommended; the complexity of Japanese tax law, particularly for those with offshore assets and income, is not well-suited to self-filing.

Social Insurance Obligations

Residents of Japan — including foreign nationals — are typically required to enrol in:

• Japanese National Health Insurance (国民健康保険) or an employer-sponsored equivalent, which provides broadly excellent healthcare coverage.
• Kosei Nenkin (厚生年金), the employees' pension insurance scheme, for those in employment.

Contributions to these schemes are mandatory and represent a meaningful additional payroll cost. Japan has totalization agreements with a number of countries — including the United Kingdom — which can prevent double payment of social security contributions for short-term assignees. The UK-Japan Social Security Agreement generally allows individuals sent to Japan by a UK employer for up to five years to remain in the UK National Insurance system rather than contributing to Japanese pension insurance. This should be confirmed with both your employer and a specialist before relying on it.

Investment Restrictions for Japan-Resident Individuals

Japan regulates the marketing and distribution of financial products under the Financial Instruments and Exchange Act (FIEA). In practice, this means:

• Many offshore investment products — including UK-based investment platforms, funds, and portfolio bonds — cannot be actively marketed to individuals resident in Japan.
• Foreign advisers who solicit business from Japanese residents risk regulatory violation.
• UK-based firms with appropriate compliance arrangements can serve their existing British national clients who have moved to Japan, provided certain conditions are met, but this varies by firm and structure.

Before relocating, it is strongly advisable to review your existing investment arrangements with your adviser and understand what can be maintained, what must be restructured, and what — if anything — you may wish to establish or encash before becoming Japanese-resident.

Japanese domestic investment options include the NISA (少額投資非課税制度) account — a tax-efficient wrapper broadly comparable to an ISA — now available in a revised permanent form since 2024, with annual contribution limits. NISA is open to foreign nationals who are resident in Japan, provided they hold a valid residence card and My Number; eligibility is based on Japanese residency rather than citizenship. Note that a NISA account cannot be retained once you cease to be Japanese-resident, and offshore investment options remain restricted under FIEA.

Banking in Japan

Opening a Japanese bank account requires a residence card (zairyu card), which is only issued after arrival and registration. The major retail banks — including Japan Post Bank, MUFG, SMBC, and Mizuho — can be slow to open accounts for foreign nationals, and English-language service varies considerably. Some newer digital options exist but are limited.

For practical purposes, most British expats in Japan maintain:

• A local Japanese account for day-to-day living expenses, rental payments, and utility bills.
• An offshore account (typically in the Channel Islands, Isle of Man, or Gibraltar) for savings, investment income, and pension receipts — particularly important during the non-permanent resident phase when keeping income offshore avoids Japanese tax.

The Japanese yen (JPY) has historically acted as a safe-haven currency and can fluctuate significantly against sterling, particularly during periods of global market stress. Currency risk management is a meaningful consideration for those with income in one currency and expenses in another.

Cost of Living

Tokyo consistently ranks in the top ten most expensive cities globally across composite cost-of-living indices. Rental costs, international school fees, and the cost of imported goods are significant. Outside Tokyo — in cities such as Osaka, Kyoto, Fukuoka, or Sapporo — costs reduce considerably while quality of life remains high.

Healthcare, public transport, and utilities are generally considered excellent value relative to their quality. Japan's social infrastructure is a material benefit for long-term residents.

Compliance Caveats

Tax rules in Japan — particularly those governing non-permanent residents, remittance, and offshore assets — are subject to change and interpretation. The five-year threshold has attracted legislative attention in recent years. Precise tax rates, thresholds, and treaty provisions should be verified with a qualified professional before making any financial decision based on this guide. Investments can fall as well as rise in value, and past performance is not a guide to future returns. This guide is for information purposes only and does not constitute personal financial or tax advice.

How Global Investments Can Help

Global Investments works with internationally mobile British nationals at every stage of an international assignment or relocation. For clients in or considering Japan, we can provide:

• UK pension reviews and NT code applications — ensuring your pension is received gross and structured appropriately for your residency status.
• Tax planning around the five-year window — modelling the optimal timing of remittances, crystallisation of gains, and restructuring before the permanent resident threshold is crossed.
• International portfolio and banking arrangements — setting up offshore structures that are compliant, accessible, and appropriate for your circumstances.
• Protection and estate planning — ensuring life cover, critical illness cover, and succession arrangements reflect your international position.

Contact our team to arrange an initial conversation about your situation in Japan.