- You must declare UK rental income in France every year — the UK-France treaty prevents double taxation but does not remove the French filing obligation
- For unfurnished rental, the Box 8TK credit neutralises both income tax and social charges — but only if you complete Form 2047 Section 6 correctly
- For furnished rental, Box 8TK neutralises income tax only — social charges still apply, and S1 holders should tick Box 8SH/8SI to get the reduced rate
- UK-only landlords cannot use the simplified Micro-Foncier regime — it requires owning a French property as well
Many UK expats in France still own property back in the UK and let it out for income. The UK still has the right to tax UK rental income. The UK-France treaty prevents genuine double taxation — but it does not remove the French declaration obligation. Both obligations run in parallel.
This guide covers both main scenarios — unfurnished lets and furnished lets — including which regime applies, the exact forms to use, how social charges work, and the important difference in how the treaty credit operates for each type.
For a broader overview of how income from UK assets is treated in France, see our guide to UK Income and French Tax: Which Country Taxes What?
The Fundamental Point: Two Sets of Obligations
Under the UK-France double tax treaty, the UK has the right to tax income from UK property. France, as your country of residence, also has the right to tax your worldwide income — including UK rental income. The treaty resolves this by requiring France to give a tax credit equal to the French tax due on that income. The effect is that the French income tax liability is neutralised to zero via Box 8TK on Form 2042.
You still have French filing obligations — the income must be declared and the forms completed correctly. And as we'll see, the social charges outcome differs significantly between unfurnished and furnished lets.
Part 1: Unfurnished UK Rental Income
Which Regime Applies
All unfurnished rental income in France is declared as property income (Revenus Fonciers). There are two regimes:
Micro-Foncier — a simplified regime applying a flat 30% allowance to your gross receipts. The remaining 70% is taxable.
The catch: you must own and actively let at least one unfurnished property in France to use this regime. Without a French property, Micro-Foncier is not available regardless of how much UK rental income you receive. If you do own French rental property, there is a second condition: total household gross unfurnished rental income (UK and French combined) must not exceed €15,000.
Both conditions must be met. Most UK expats with only UK rental property will not qualify — Régime Réel applies by default.
Régime Réel — you deduct actual expenses from gross receipts to arrive at a net profit or loss, calculated on Form 2044.
UK-only landlords: If all your rental property is in the UK and you own nothing in France, Micro-Foncier is not available. Régime Réel is your only option.
The 3-year lock-in: If you own French rental property, could use Micro-Foncier, but choose Régime Réel instead, that election is irrevocable for 3 years. UK-only landlords have no choice — Régime Réel applies regardless.
Which is more beneficial? Micro-Foncier is simpler and works well when your actual expenses are low. Régime Réel is better when you have significant costs — mortgage interest, repairs, agent fees, insurance — that together exceed 30% of gross receipts. A loss under Régime Réel can be offset against other property income or, up to a cap, against your global income.
If you have both UK and French unfurnished rental: both must be declared under the same regime. You cannot use different regimes for different properties.
How to Declare It — Forms and Boxes
Step 1: Form 2047 — Section 4 (property income)
Enter the UK property details:
- Country: Royaume-Uni
- Address of the property
- Micro-Foncier: enter gross rent received
- Régime Réel: enter net profit from Form 2044
Step 2: Form 2047 — Section 6 (mandatory for UK property)
This is the section that triggers the treaty credit:
- Country: Royaume-Uni
- Type of income: Revenus fonciers
- Micro-Foncier: enter gross rent. Régime Réel: enter net profit
- Carry the total to the summary line at the end of Section 6
For a full explanation of how Form 2047 works, see our dedicated guide.
Step 3: Form 2042 — Main Return
- Micro-Foncier: Box 4BE (gross receipts — 30% allowance applied automatically)
- Régime Réel: Box 4BA (net profit from Form 2044)
- Enter the same figure in Box 4BK (Micro-Foncier) or Box 4BL (Régime Réel) — this identifies the UK-source portion eligible for the treaty credit
If you have both UK and French unfurnished rental, add both together and enter a single combined total in Box 4BE or 4BA. Enter only the UK portion in Box 4BK or 4BL.
Step 4: Form 2042 — Box 8TK
Enter the total from Form 2047 Section 6. This is the treaty credit that neutralises French income tax AND social charges to zero on UK unfurnished rental income. Without Box 8TK, you will be taxed twice.
Form 2047 Section 6 and Box 8TK are the two steps most commonly missed on UK rental declarations. Taxpert's filing assistant produces a personalised guide that includes information about Box 8TK.
Social Charges on UK Unfurnished Rental
Social charges are neutralised to zero via the Box 8TK credit mechanism under the treaty. No social charges are due on UK unfurnished rental income — regardless of S1 status.
This is different from French unfurnished rental income, where social charges apply at 17.2% regardless of Box 8TK. The treaty exemption covers both income tax and social charges for UK property only.
Part 2: Furnished UK Rental Income
LMNP vs LMP — Which Applies?
Furnished rental in France falls into two categories:
- LMNP (Loueur en Meublé Non Professionnel) — non-professional furnished landlord. This is the standard status for most UK expats with a single furnished UK rental property.
- LMP (Loueur en Meublé Professionnel) — professional furnished landlord. This applies only if two conditions are both met: gross furnished rental receipts exceed €23,000 AND rental receipts also exceed all other professional income in the household.
Most UK expats with a single furnished UK rental property will be LMNP. LMP status has significantly different tax and social security implications and is outside the scope of this article.
Important: Exceeding €23,000 alone does not make you LMP — both conditions must be met. However, exceeding €23,000 does trigger a social security contribution requirement regardless of LMP/LMNP status. If you are near this threshold, seek advice before filing.
Micro-BIC or Régime Réel?
Micro-BIC applies a flat-rate allowance to gross receipts:
- Standard furnished let (including unclassified holiday lets): 30% allowance — ceiling €15,000 gross receipts
- Classified gîte, tourist let, or chambres d'hôtes: 50% allowance — ceiling €77,700 gross receipts
A classified furnished holiday let is one that has been officially rated by an accredited body — such as Gîtes de France, Clévacances, or A tout France — and awarded a star rating from 1 to 5. Classification is voluntary but the financial benefit is significant: classified properties qualify for the 50% allowance and €77,700 ceiling, while unclassified lets (including most Airbnb-type properties) are limited to the 30% allowance and €15,000 ceiling.
Note: these are the 2026 figures following the changes introduced for 2025 income. The ceilings and allowances for unclassified lets were significantly reduced from the previous year.
Régime Réel — deduct actual expenses and depreciation, calculated on Form 2031. No lock-in — you can switch between Micro-BIC and Régime Réel each year.
UK property Micro-BIC — important difference: For French furnished rental, you enter gross receipts and the tax office applies the allowance automatically. For UK furnished rental under Micro-BIC, you must manually subtract the allowance before entering the figure. Enter the taxable profit (gross receipts minus allowance), not the gross figure.
See the rental allowances on the Taxpert reference data page →
How to Declare It — Forms and Boxes
Step 1: Form 2042-C PRO — Supplementary Return
Under non-professional furnished rental (LMNP):
- Micro-BIC (standard let): enter taxable profit after manually subtracting the 30% allowance
- Micro-BIC (classified gîte): enter taxable profit after manually subtracting the 50% allowance
- Régime Réel: enter net profit from Form 2031
For LMNP UK property, report the income in the foreign source sub-section to prevent incorrect monthly tax instalments being triggered.
If you have both UK and French furnished rental, add the taxable profit from both together and enter a single combined total.
Step 2: Form 2047 — BIC Section (business income)
Under non-salaried professional income — commercial and industrial profits (BIC):
- Enter the net taxable profit (after allowance or actual expenses)
- This identifies the UK as the income source
Step 3: Form 2047 — Section 6 (mandatory for UK property)
Under income subject to the French tax credit mechanism:
- Enter the same net taxable profit
- Carry the total to the summary line at the end of Section 6
Step 4: Form 2042 — Box 8TK
Enter the total from Form 2047 Section 6. For UK furnished rental, Box 8TK neutralises income tax only — unlike unfurnished rental where it neutralises both income tax and social charges. Social charges still apply on UK furnished rental income.
Social Charges on UK Furnished Rental
This is the key difference from unfurnished rental:
UK furnished rental: The Box 8TK credit neutralises income tax only. Social charges still apply. This applies regardless of S1 status.
S1 holders: Tick Box 8SH (Declarant 1) / 8SI (Declarant 2) to apply the reduced solidarity levy rate instead of full social charges. This applies to LMNP furnished rental. See our guide on the S1 certificate for full details.
Common Mistakes
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Not declaring UK rental income in France because you're already declaring it in the UK. Both declarations are required. The treaty prevents double taxation but does not remove the French filing obligation.
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Thinking the Box 8TK credit means you pay nothing. The credit neutralises the French income tax. But you must still complete the declaration, use the correct forms, and — for furnished rental — account for social charges separately.
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UK-only unfurnished landlords trying to use Micro-Foncier. Micro-Foncier requires owning and letting a French property in addition to the UK one. If all your rental property is in the UK, Régime Réel is mandatory.
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Entering gross receipts for UK furnished rental under Micro-BIC. For UK property, you must manually subtract the allowance and enter the taxable profit. For French furnished property, the tax office does this automatically.
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Missing Form 2047 Section 6. This section is mandatory for UK rental income and is what triggers the Box 8TK credit. Without it, the credit cannot be applied and you will overpay French tax.
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Assuming social charges on UK furnished rental are neutralised by Box 8TK. They are not. Box 8TK neutralises income tax only for furnished rental. Social charges still apply — this is different from unfurnished rental where 8TK neutralises both.
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Electing Régime Réel for unfurnished rental without understanding the commitment. If you own French rental property, could use Micro-Foncier, but choose Régime Réel instead — that election is irrevocable for 3 years.
Frequently Asked Questions
I declare my UK rental income on a UK Self Assessment return. Do I still need to declare it in France?
Yes. Both obligations run in parallel. If you are a French resident with UK rental income, you must declare it in France as part of your worldwide income declaration. The Box 8TK credit in France ensures you are not doubly taxed, but both returns are required.
My UK rental income is small — under £5,000 a year. Does it still need to be declared in France?
Yes. There is no minimum threshold for foreign rental income in France. All rental income, however small, must be declared.
My UK property is managed by a letting agent who deducts their fees. Do I declare the gross rent or the net amount I receive?
For Micro-Foncier, you declare the gross rent before agent fees — the 30% allowance covers all expenses including agent fees. For Régime Réel, you declare gross receipts on Form 2044 and deduct actual expenses including agent fees as an allowable cost.
Can I offset a loss on my UK rental property against my French income?
Under Régime Réel for unfurnished rental, a loss can be offset against other property income (Box 4BB) or against global income up to the applicable cap (Box 4BC). Unused deficits can be carried forward using Box 4BD. Under Micro-Foncier, losses cannot be created or carried forward.
I let my UK property furnished as a holiday let. Does the 2026 Micro-BIC change affect me?
Yes. From 2025 income (declared in 2026), the Micro-BIC ceiling for UK furnished holiday lets is €15,000 with a 30% allowance — reduced from the previous 50%. If your gross receipts exceeded €15,000 in 2025, you cannot use Micro-BIC and must use Régime Réel instead.
The higher ceiling of €77,700 with a 50% allowance applies only to officially classified French properties — properties in the UK cannot be classified under the French system, so the lower ceiling always applies to UK holiday lets regardless of any UK star rating or accreditation.
Do I need to declare the UK rental property as a foreign account on Form 3916?
No. Form 3916 is for foreign financial accounts — bank accounts, investment accounts. A UK rental property is a real asset, not a financial account, and does not require Form 3916 declaration. However, any UK bank account into which your rental income is paid does need to be declared on Form 3916.