ISAs and SIPPs in France: What UK Expats Need to Know About Tax (2026)

Two of the most common UK financial vehicles — the ISA and the SIPP — work very differently in France. The ISA tax-free wrapper doesn't exist in French law. The SIPP is treated as a private pension. Here's what each means for your French tax return.

Most UK expats moving to France have held ISAs or SIPPs for years — often decades. They're central to how people in the UK structure savings and retirement. But French tax law doesn't recognise either of them as having any special status. Once you become a French tax resident, the UK tax advantages fall away and the income or gains from these accounts are subject to French tax in full.

This article covers how France treats both — what's taxable, when, at what rate, and how to declare it.

For the broader picture on how investment income is taxed in France, see our guide to PFU vs Progressive Tax: Which Is Better for Your Investment Income?. For private pension income including SIPP drawdown, see UK Private Pension: How It's Taxed in France.

ISAs: The Tax-Free Wrapper That Isn't

In the UK, an ISA (Individual Savings Account) shelters interest, dividends, and capital gains from tax entirely. The income grows tax-free and can be withdrawn tax-free. That's the whole point of the wrapper.

France does not recognise this wrapper. There is no provision in French tax law, and no provision in the UK-France double tax treaty, that grants ISAs any special status.¹ Once you are a French tax resident, the income and gains generated inside your ISA are taxable in France in exactly the same way as income and gains from any other investment account.

This means:

• Interest from a Cash ISA is taxable as investment income
• Dividends from a Stocks and Shares ISA are taxable as dividend income
• Capital gains from selling shares or funds inside a Stocks and Shares ISA are taxable as capital gains

The fact that the UK treats this income as exempt is irrelevant for French tax purposes. France taxes you on your worldwide income — and the wrapper your income sits in makes no difference.

This is one of the most common surprises for UK expats. Many people arrive in France with years of accumulated ISA savings, assuming the tax-free status travels with them. It doesn't. The ISA wrapper is a feature of UK domestic tax law — it has no legal effect in France.¹

What Rate Applies to ISA Income

All three types of ISA income — interest, dividends, and capital gains on securities — are subject to the PFU (Prélèvement Forfaitaire Unique) flat tax at 31.4%. This breaks down as 12.8% income tax plus 18.6% in social charges. See the PFU flat tax and social charges rates on the Taxpert reference data page →

You can elect to use the progressive income tax scale instead of PFU, but this is an all-or-nothing election — it applies to all your investment income for the year, not just ISA income. Whether this works in your favour depends on your marginal tax rate. For most people in or near the 11% bracket, the progressive scale produces a lower tax bill than 31.4% PFU. See our PFU vs Progressive Tax guide for how to assess this.

S1 holders: The social charges element on investment income for S1 holders is the solidarity levy at 7.5% rather than the full 18.6% social charges rate. This gives S1 holders a significantly lower combined rate — 12.8% income tax + 7.5% solidarity levy = 20.3% under PFU rather than 31.4%.

How to Declare ISA Income

ISA income is declared in exactly the same way as income from any other UK investment account. There are no special boxes or forms — you simply declare by income type.

Dividends from a Stocks and Shares ISA:

• Form 2047, Section 2, Line 220 (Revenus n'ouvrant pas droit à un crédit d'impôt — income not giving rise to a foreign tax credit) — enter the gross dividend amount here. Line 221 is a calculated total that populates automatically — do not enter a figure there. Line 222 carries the total forward to Box 2DC on Form 2042
• Form 2042, Box 2DC — total gross dividends (all sources combined)
• If UK tax was withheld at source (unusual for most dividend payments to French residents) use Route B on Form 2047 Section 2 and claim the treaty credit in Section 7 → Box 8VL on Form 2042 C

Interest from a Cash ISA:

• Form 2047, Lines 250, 251 and 252 — enter the gross interest amount on Line 250 and repeat the same figure on Lines 251 and 252
• Form 2042, Box 2TR — total gross interest (all sources combined)
• Note: there is no French tax credit mechanism for UK interest withheld at source — always declare the full gross amount and reclaim any UK withholding directly from HMRC

Capital gains from selling within a Stocks and Shares ISA:

• Form 2042, Box 3VG — net capital gains on securities
• Capital losses can be carried forward for up to 10 years and offset against gains of the same type in future years

Note on totals: Boxes 2DC, 2TR, and 3VG represent your household total across all accounts and all sources — UK bank accounts, ISAs, other foreign accounts. You don't create separate entries for ISA income. It all goes into the same boxes as your other investment income.

S1 holders: Tick Box 8SH (Declarant 1) or 8SI (Declarant 2) on Form 2042 C under Revenus de source étrangère — cotisations sociales. This triggers the 7.5% solidarity levy on your investment income rather than the full 18.6% social charges rate. For a mixed household where only one partner holds an S1, also enter the S1 holder's individual share of total investment income in Box 8RC — this isolates their portion at the reduced rate.

Pulling together dividends and interest from multiple accounts — ISAs, UK savings accounts, foreign bank accounts — converting each payment to euros at the correct exchange rate, and entering the combined totals in the right boxes is exactly the kind of consolidation work Taxpert's filing assistant handles. Enter your accounts once and it calculates your combined totals and identifies the correct boxes.

The Form 3916 Declaration for ISA Accounts

Separately from declaring the income, you must declare the existence of your ISA account on Form 3916 each year. An ISA held with a UK provider is a foreign financial account for French tax purposes and must be declared annually — regardless of whether you received income from it that year, and regardless of the balance.

The penalty for failing to declare a foreign account is €1,500 per account per year under Article 1736 of the Code Général des Impôts — this applies to accounts held in countries that have a tax treaty with France, including the UK. The penalty rises to €10,000 per account if the account is held in a non-cooperative jurisdiction. The €750 figure sometimes cited applies only to specific incomplete data omissions, not to an undeclared account.

A Stocks and Shares ISA and a Cash ISA held with the same provider are two separate accounts and each requires its own Form 3916 entry. A Junior ISA held in a child's name who is part of your foyer fiscal also needs to be declared.

Should You Keep Your ISA?

This is a financial planning question rather than a purely tax one — but it's worth raising. Some advisers suggest that once you are France-resident, there is no ongoing tax advantage to keeping money inside an ISA wrapper, since France ignores it entirely. The question is whether there's a strategic reason to keep the ISA structure intact — for example, if you plan to return to the UK at some point, when the tax-free status would be restored.

If you have no plans to return to the UK, some advisers suggest reviewing whether a French assurance vie might be a more tax-efficient structure for holding your savings in France — it has its own favourable tax treatment after eight years and different rules on succession. This is a decision that depends on your individual circumstances and is worth taking specific advice on before acting. Moving money out of an ISA is irreversible — you cannot re-subscribe once the money is out.¹

SIPPs: Treated as a Private Pension

A SIPP (Self-Invested Personal Pension) is treated in France as a private pension — specifically as a pension de retraite de source étrangère (foreign source retirement pension). France does not distinguish between a SIPP and any other private pension scheme for tax purposes.²

This means:

• Regular drawdown income from a SIPP is declared as pension income — on Form 2047 Line 12 and Form 2042 Box 1AM/1BM — and taxed through the progressive scale after the 10% pension abatement
• The SIPP wrapper provides no ongoing tax shelter in France — income is taxable when drawn, just like any other pension
• Gains growing inside an undrawn SIPP are not taxable while they remain inside the pension — they are only taxed when drawn as income or taken as a lump sum

The flat rate (7.5%) election for lump sums: Available for a qualifying SIPP lump sum, but conditions apply:

• Must be a one-off final settlement of the pot — not regular drawdown
• The pension must be a qualifying scheme
• No tax-deductible contributions were made while a French tax resident (under Article 163-0 A CGI — rarely an issue for UK SIPPs as you can't get UK tax relief as a non-resident)

If conditions are met, the 7.5% rate applies after the 10% abatement. Full details in our Pension Lump Sums guide.

Gains within an undrawn SIPP: While your SIPP remains undrawn, internal gains are not taxable in France. They only enter the French tax calculation when you take income or a lump sum. No annual declaration of notional gains is required.

UK tax on SIPP income: Under Article 17 of the UK-France treaty, private pension income — including SIPP drawdown — is taxable only in France. You should notify HMRC that you are a French resident so UK tax is not deducted at source. If UK tax is being deducted in error, declare the full gross amount on your French return and reclaim the UK tax from HMRC.

The Form 3916 Declaration for the SIPP Account

Like ISAs, SIPPs held with UK providers are foreign financial accounts and must be declared on Form 3916 each year — including years in which no drawdown is taken. The account exists and must be declared. The same €1,500 per account per year penalty applies for failure to declare.

Common Mistakes

1. Assuming ISA income is tax-free in France. It isn't. The UK tax-free wrapper has no legal effect in French law. All income and gains generated inside an ISA are fully taxable in France in the year they arise.

2. Not declaring ISA income because it wasn't paid out. If your Stocks and Shares ISA reinvests dividends automatically, those dividends are still taxable in France in the year they are credited to the account — not when you eventually withdraw the money. Reinvested income is still income.

3. Declaring SIPP drawdown as capital rather than pension income. Regular drawdown from a SIPP is pension income — not a capital withdrawal. It goes on Form 2047 Line 12 and Box 1AM/1BM, not on the capital gains forms. Treating it as capital can result in the wrong rate being applied.

4. Forgetting Form 3916 for ISA and SIPP accounts. The income declaration and the account existence declaration are two entirely separate obligations. Declaring the income correctly does not satisfy the Form 3916 requirement — you need to do both every year the account exists.

5. Continuing to pay into a UK ISA after becoming France-resident. You cannot pay into a UK ISA if you are not a UK tax resident. Contributions made as a French resident are not permitted under UK ISA rules — any such contributions would need to be removed. This is a UK rule, not a French one, but it's worth flagging.

6. Not reclaiming UK tax wrongly withheld on SIPP drawdown. If your SIPP provider is still deducting UK income tax, submit the HMRC double taxation relief form and reclaim it. Always declare the gross amount on your French return.

Frequently Asked Questions

I have a large Cash ISA. Do I need to declare the interest every year even if I don't touch it?

Yes. Interest credited to a Cash ISA is taxable in France in the year it arises, regardless of whether you withdraw it. The fact that it stays inside the ISA wrapper makes no difference — France looks through the wrapper to the underlying income.

I have a Stocks and Shares ISA that reinvests dividends automatically. Do I still need to declare them?

Yes. Reinvested dividends are still dividends — they are income in the year they are credited, even if they are immediately used to buy more units. You should receive an annual statement from your ISA provider showing dividends paid or reinvested during the tax year. That figure is what you declare on your French return.

Does the taper relief on shares apply to shares inside an ISA?

No. The abattement for durée de détention on capital gains applies to shares held directly outside a tax wrapper. Shares held inside an ISA are not eligible for this relief — the gains are taxable in full under PFU or the progressive scale.

My SIPP is still fully invested and I haven't started drawdown. Do I have any French tax obligations now?

Your main obligation is the annual Form 3916 declaration of the SIPP as a foreign account. You don't need to declare any income while no drawdown is taken and no lump sum is withdrawn. Gains growing inside the undrawn SIPP are not separately taxable — they only come into the French tax calculation when you draw income.

I have both a UK ISA and a French assurance vie. Do I declare them differently?

Yes — completely differently. The ISA is a foreign account (Form 3916) and its income is declared as investment income in the normal boxes. The French assurance vie has its own specific declaration route and tax treatment, including favourable rates after eight years. They are treated as entirely separate income types on your French return.

Can I transfer my ISA to a French assurance vie?

You can close your ISA and invest the proceeds in an assurance vie — but you cannot transfer directly. Closing an ISA means you lose the UK tax-free wrapper permanently, so this is an irreversible decision. Whether it makes financial sense depends on your individual situation, your plans regarding the UK, and the specific assurance vie product. Take regulated advice before acting.

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