I'm a financial adviser and these are the common mistakes that people make when moving to France

As a wealth planner, I have noticed two distinct phases in a newcomer's journey.

First, there are the general myths about financial advice that stop people seeking help.

Second, there are the specific technical shocks of the French system that catch out even the savviest investors.

1. Do not believe the myths

Many believe that international advice is only for the wealthy, but currency exchange rates and cross-border tax implications affect everyone. Specialist advice can make the difference between a compliant and a costly financial life.

Others believe a financial adviser in their country of origin can handle their affairs. This is a dangerous assumption.

UK advisers, for example, may face restrictions on advising clients who are resident outside the UK, depending on their regulatory permissions and the services involved.

Do not rely on online resources either, as French regulations change rapidly. Advisers navigate these shifts daily, so self-research can prove a false economy.

2. Establish your tax residency

In France, counting the number of days you spend here is only one test of tax residency.

Your foyer (home or family centre) is another. If your spouse and minor children live in France, or if your centre of economic interests is here, you may be considered a French tax resident even if you work abroad and spend only weekends in France.

3. Declare your foreign accounts

In the UK, you generally do not have to tell HMRC about every bank account you hold simply because you own it. In France, residents must declare certain accounts and financial arrangements held abroad.

Upon becoming a French tax resident, you must declare relevant foreign bank accounts, life assurance policies and certain digital asset accounts, including those used for cryptocurrency, using Form 3916 or 3916-bis, as applicable.

The penalty for failing to declare a reportable account is generally €1,500 per account, per year. This can apply even to dormant accounts or a UK savings account containing just £5.

4. Consider alternatives to ISAs

France does not recognise the tax-free status of a UK individual savings account (ISA). Its income and gains may therefore be taxable under French rules.

This means that dividends and interest may be taxable in France, and the account does not automatically benefit from the tax treatment available to French savings products. UK residency rules also generally restrict contributions to ISAs by people who are no longer UK residents.

One alternative to consider is assurance vie. This is not simply life insurance; it is also a tax-efficient investment wrapper under French rules.

Unlike a directly held share portfolio, where investment income may be taxed as it arises, an assurance vie can allow investment growth to accumulate without immediate French income tax, with taxation generally arising when money is withdrawn. The precise treatment depends on the policy, its duration and the investor's circumstances.

5. Understand inheritance rules

The UK and France take different approaches to inheritance taxation. In the UK, inheritance tax is generally charged on the estate, whereas in France inheritance tax is generally paid by each beneficiary.

This distinction is particularly important for blended families:

• Spouses: generally exempt from French inheritance tax.

• Biological children: benefit from substantial tax-free allowances.

• Stepchildren: may face a tax rate of 60% on inheritances, after any applicable allowances, unless specific legal arrangements or exceptions apply.

Many people rely on the EU Succession Regulation, commonly known as Brussels IV, to elect the law of their nationality in their will and address French forced-heirship rules (réserve héréditaire).

A 2021 French law, introducing Article 913 of the Civil Code, sought to protect children who might otherwise be disinherited under foreign succession law in certain circumstances. The interaction between this provision and foreign succession laws is complex, so anyone relying on an election of UK law should obtain specialist advice on their particular circumstances.

6. Distinguish income tax from social charges

Expatriates often confuse income tax with social charges (prélèvements sociaux).

For 2026, the rates cited for investment income are 31.4% in total (12.8% income tax and 18.6% social charges) for many types of income, and 30% (12.8% income tax and 17.2% social charges) for certain categories, including some income from assurance vie, regulated savings and property. The applicable rate depends on the type of income and the relevant rules.

If you are a UK state pensioner holding an S1 form, you may be exempt from the CSG and CRDS components of social charges on certain pension and investment income. In some cases, this can reduce the social charges due on relevant investment income to 7.5%.

We often see S1 holders overpaying tax because the exemption has not been correctly applied to their returns.

These are six of the financial mistakes I see newcomers make when moving to France. Understanding the rules early can help avoid costly surprises and ensure your financial arrangements are appropriate for your new life.