UK Income and French Tax: Which Country Taxes What? (2026)

The rulebook that decides who taxes your UK income when you live in France. Without it, both countries could tax the same money at the same time. This guide explains how it works, which income types go where, and the single most common mistake that catches UK expats out every year.

• The France-UK tax treaty assigns each type of income to one country — understanding which country taxes what is the foundation of your entire tax position
• Declaring UK income in France doesn't mean France taxes it — but you must declare everything regardless, including income taxed only in the UK
• Government Service Pensions are taxed only in the UK, but France still uses them to work out the rate applied to your other income
• The treaty covers income tax only — social charges are a separate obligation entirely, determined by your S1 status

The France-UK Double Taxation Agreement determines which country has the right to tax each type of income — and what the other country must do as a result. Understanding it is the foundation of your entire tax position as a UK expat in France.

The current convention was signed on 19 June 2008 and entered into force on 18 December 2009. It remains the governing document for all UK-France tax relationships.

For a broader overview of how tax works in France, see how the French tax system works.

Why the Treaty Exists

When you move to France but continue to receive income from the UK, two countries have a potential claim on that money. Without an agreement, both France and the UK could technically charge tax — France because you live there, the UK because the income originates there.

The treaty removes that problem. It creates a legal rulebook that clearly assigns taxing rights — and makes living between the two countries viable.

How Double Taxation Is Prevented — The Six Mechanisms

There are six primary mechanisms used to prevent double taxation for UK expats. Each applies to different income types and works differently on your return.

1. Tax Credit Equal to the French Tax (Box 8TK)

Used for income that, under the treaty, is taxable only in the UK — but must still be declared in France to determine your overall tax rate.

How it works: you declare the gross income, the system calculates the French tax due on it, then provides an equal credit to cancel it out. The result is zero French income tax and zero social charges on this specific income.

Applies to: UK Government Service Pensions (civil service, police, military, local authority), UK rental income, and certain professional profits.

2. Tax Credit Equal to the Foreign Tax (Box 8VL / 8VM)

Used when the treaty allows both countries to tax the same income — but France agrees to subtract the UK tax already paid from your French bill.

How it works: you declare the gross amount and the actual UK tax paid. France calculates its tax, then subtracts a credit representing the UK tax — often capped at 15% or 17.7% depending on income type.

Applies to: UK dividends, interest, and certain royalties.

3. Exemption with Rate Effect

Some income is strictly exempt from French tax by treaty — but France uses it to calculate the rate applied to your other French-taxable income. It is not directly taxed, but it pushes your other income into a higher progressive bracket. See the section below for a full explanation.

4. S1 Form Exemption for Social Charges (Box 8SH / 8SI)

Not an income tax credit — but a vital mechanism to prevent double social contributions for those already covered by the UK healthcare system.

By declaring your S1 status, you signal that you are not a burden on the French social security system. This exempts UK State and private pensions from French social charges entirely.

See our S1 guide and social charges in France.

5. Refund of Advance Payments (Box 2CK)

For investment income, French banks may withhold a 12.8% advance payment on income tax during the year. The amount already taken is reported in Box 2CK and acts as a tax credit subtracted from your final liability — ensuring the same income is not taxed twice within the same year.

6. Direct Recovery from UK Authorities

If the UK withholds more tax than the treaty allows, France will only credit the permitted amount. You must then apply directly to HMRC to reclaim the excess.

Example: if the treaty limits UK tax on dividends to 15% but the UK deducts more, France credits only 15%. You must pursue the difference separately from HMRC.

Which Income Type Goes Where

Each income type has its own detailed guide in the Tax Treaties & Your Income section.

The Most Misunderstood Part — The Rate Effect

This is what catches people out most often.

Even if your UK Government Service Pension is exempt from French income tax, France still wants to know about it. You declare it, France adds it to your other income to determine which tax bracket applies — then taxes only your non-exempt income at that higher rate.

The elevator analogy makes this clear:

Imagine the French tax system as a building with different floors:

• Ground Floor: 0%
• 1st Floor: 11%
• 2nd Floor: 30%
• 3rd Floor: 41%

Without the rate effect: you have €2,000 of French savings interest and stand on the Ground Floor. You pay close to nothing.

With the rate effect: France sees your £20,000 Government Pension. They don't tax it — but they use it to press the lift button. Because £20,000 comes in, they decide you're not a Ground Floor person. Your lift goes to the 2nd Floor (30%).

Now when you pay tax on that €2,000 of interest, you pay 30% — not 0%.

The pension is protected — France never touches the £20,000. But your other income becomes more expensive because the pension revealed your true income level.

The rule: declare everything. Let the treaty determine what you owe. Never decide not to declare something because you think France cannot tax it.

What the Treaty Does Not Cover

The treaty is an income tax agreement only.

Social charges are entirely separate and not covered. France can apply social charges to most income types regardless of what the treaty says about income tax. Your protection against social charges comes from your S1 — not the treaty.

Wealth tax (IFI) is a tax on property assets, not income. Not covered.

Local property taxes — taxe foncière and related charges — are outside the treaty's scope entirely.

What You Need to Do in Practice

Step 1 — Complete the France Individual DT Form

If you have UK-source income that the treaty assigns to France — a State Pension, private pension, interest, royalties — you need to stop the UK deducting tax at source.

The process: complete the form → send to your local French tax office for certification → send certified form to HMRC → HMRC issues a no-tax code to your income provider. One-time process unless your circumstances change.

Step 2 — Declare everything on your French return

Every income type — whether taxed in France, taxed in the UK, or exempt — must appear on your French return. Use Form 2047 to identify foreign-source income by country and type. The treaty exemptions and credits are then applied through the correct boxes on Form 2042.

Common Mistakes with the France-UK Treaty

1. "It's taxed in the UK so I don't need to tell France." The treaty determines taxing rights — it does not remove the obligation to declare. Everything must appear on your French return.

2. Not completing the France Individual DT form. Many expats spend years having UK tax deducted at source unnecessarily. HMRC will keep deducting until you tell them not to.

3. Assuming social charges are covered by the treaty. They are not. Social charges are a separate obligation determined by your income type and S1 status.

4. Confusing exemption with invisibility. Exempt income — Government Service Pensions in particular — still affects your French tax bill via the rate effect. Declare it.

Treaty Reference

Convention between the United Kingdom and the French Republic for the Avoidance of Double Taxation, signed 19 June 2008, in force 18 December 2009.

Official sources:

• HMRC: UK/France Double Taxation Convention (2008)
• impots.gouv.fr: Convention fiscale franco-britannique

Frequently Asked Questions

What is the France-UK double tax treaty?

A legal agreement that determines which country has the right to tax each type of income for people with connections to both countries. It prevents the same income being taxed twice — either by giving one country the sole taxing right or by allowing a credit against tax already paid in the other country.

Does the treaty mean I don't pay tax in France on my UK pension?

It depends on the type. State and private pensions are assigned to France — you pay tax in France, not the UK. Government Service Pensions are assigned to the UK — France exempts them from income tax but uses them to determine the rate applied to your other taxable income.

Do I still need to declare income that the treaty exempts from French tax?

Yes — always. France uses it to calculate the rate applied to your other income. Failing to declare is treated as non-disclosure regardless of whether tax is owed.

Does the treaty cover social charges?

No. The treaty covers income tax only. Social charges are determined by your income type and S1 status.

What is the France Individual DT form and do I need it?

It instructs HMRC to stop deducting UK tax at source on income assigned to France. Complete it once, certify it at your local French tax office, send it to HMRC. They issue a no-tax code to your income provider.

What is the rate effect on exempt income?

The method France uses to ensure that treaty-exempt income still influences your overall tax rate. France adds exempt income to your taxable income to determine which bracket applies — then taxes only the taxable portion at that rate. See the elevator analogy above.