Income tax declaration in France

Applicable to:  Members of the personnel


This page is intended to provide members of the personnel who are resident of France with general information on how financial and family benefits or occasional subsistence allowances (the latter concerning certain associated members of the personnel) should be indicated on the income tax declaration form.

The information given below does not absolve members of the personnel from the requirement to comply with the national tax laws applicable to them (c.f. Article S V 2.02 of the Staff Rules and Regulations), especially those of the Host State in which they reside, with which they must be acquainted and by which they must abide.

For any other income, members of the personnel should refer to the notes sent out with the income declaration form. The local Service des impôts des particuliers (SIP, private citizens’ tax office) will then determine the applicable taxation, if any.

In addition, in order to help members of the personnel to complete their income declaration forms, the Valserhône SIP has prepared a document containing responses to the most common questions received by the HR Department, which the Organization has decided to publish in agreement with the SIP. A recording of the public meeting that took place on 26 February 2019 to discuss these questions, including the presentation by representatives of the Valserhône SIP, is also available.

Please address all specific questions directly to your local SIP (Service des impôts des Particuliers).


1. Who must complete a declaration form?

All members of the personnel (irrespective of the category of personnel to which they belong) who are residents of France (see point 1.1 of the document prepared by the Valserhône SIP) must complete a declaration. Consequently, members of the personnel must themselves determine whether or not they are “domiciled in France” by referring to the criteria laid down by the SIP, namely:

  • if their primary residence is in France (in particular if their spouses/partners and/or children reside with them); or
  • if they resided in France for more than 183 days (6 months) of the corresponding fiscal year.

However, only the SIP can assess individual circumstances. In the event of a specific problem, members of the personnel should contact their local SIP.


  • CERN pensioners

CERN pensioners are taxed under the common law system, including the CERN pension. Section 3 below does not therefore apply to this income.

  • Former members of the personnel benefiting from CERN unemployment insurance benefits​

Unemployment insurance benefits paid to former CERN members of personnel are taxed under the common law system. Section 3 below does not therefore apply to this income.

2. When to file an income tax declaration

The online income tax declaration is now mandatory for everyone. Only persons who are technically or otherwise unable to complete an online form may continue to submit a paper form.

Members of the personnel who have opted for the "paperless" option will be notified of the opening of the online service via the e-mail address they have indicated in their personal account, and will be able to complete their income tax declaration when the online service is opened.

Those who have not opted for the "paperless" option, or are not completing an online form, will receive the paper form in batches sent out from mid-April to the end of April. Those who do not receive the form directly, and in particular those who are filing a tax declaration form in France for the first time, will be able to download it from the Ministry of Economy and Finance website (type "formulaire" in the search box) or to obtain it from the SIP, the Centres des Finances Publiques (treasuries) or the local town hall.

The deadlines for submitting the online declaration have been set as:

  • 04/06/2020 for departments 01 to 19,
  • 08/06/2020 for departments 20 to 54,
  • 11/06/2020 for departments 55 to 976.

The deadline for submitting paper declarations is set at 12/06/2020, based on the date of the postmark (including for non-residents in France required to file a declaration).

3. How to complete the declaration form

3.1 Using the internal taxation certificate

Each year, the Organization levies an internal tax (calculated according to the CERN scale) on the financial and family benefits that it pays to the members of the personnel. Those members of the personnel receive from the CERN administration an internal taxation certificate and are therefore exempt from national taxation on financial and family benefits paid by CERN.

In any case:

  1. Under the heading “Traitements, Salaires”, they must not indicate the amount of the financial and family benefits paid by CERN, which are subject to internal taxation by the Organization.
  2. They must tick box 8FV, "Divers", in Part 8 of the form. On the online declaration, this part is accessible in step 3 "Revenus et charges" under the heading "Divers", by ticking the box entitled "Taux moyen d'imposition des Non-résidents, retenue à la source, comptes à l'étranger, reprises de réductions ou de crédit d'impôt, etc.".
  3. They must include a note stating: “Membre du personnel du CERN assujetti à l’impôt interne du CERN et, à ce titre, exonéré d’impôt sur les prestations financières et familiales versées par le CERN.” (Member of the CERN personnel subject to internal CERN taxation and therefore exempt from taxation on the salary and emoluments paid by CERN). On the online version, the note must be entered at the end of the form under the heading “Informations – Mention expresse”. If they submit a paper form, the note must be added on page 2 under the heading "Informations" or on a separate sheet if this section is already pre-filled.
  4. The internal taxation certificate that is issued in accordance with article R V 2.05 of the Staff Regulations:
    - is to be sent via the secure messaging service by connecting to the "espace particulier" on the site,
    - or failing that is to be sent by post to the local SIP (Service des impôts des Particuliers), along with the reference number of the online declaration, or
    - must be attached to the paper declaration.

E-mails cannot be used for this purpose.

Members of the personnel are invited to consult the FAQ prepared by the Valserhône SIP.

3.2 Using the financial certificate

Members of the personnel who have received a financial certificate from the CERN administration in February 2020, and who have decided to use it instead of the new internal taxation certificate issued in April 2020, must complete their French tax declaration as follows:

  1. Under the heading "Traitements, salaires - salaires de source étrangère avec crédit d'impôt égal à l'impôt français" (box 1AF) and the heading "Revenus de source étrangère ouvrant droit à un crédit d'impôt égal à l'impôt français" (box 8TK): report the salary and any revenues (including the subsistence allowance) already taxed in their home country (the same amount in both boxes);
  2. Under the heading "autres salaires imposables de source étrangère" (box 1AG): report the salary and any revenues (including the subsistence allowance) not taxed by their home country;
  3. If the subsistence allowance received through CERN is reported under 1AG (and therefore taxable in France), actual professional expenses should be reported under the heading "Frais réels" (box 1AK). These costs would be deducted from the taxable income if considered by the French authorities as justified and linked to the professional activity of an associated member of the personnel sent by the employer to work at CERN. These costs may include rent, local tax (taxe d'habitation), water/electricity bills, and any other expenses justified by the member of the personnel's presence in the region for professional activities. A detailed calculation of this amount should be attached to the declaration; actual evidence (such as bills) must be kept by the member of the personnel as they may be required by the tax authorities later for verification.

Very important: Members of the personnel who use a financial certificate and not an internal taxation certificate must not tick the 8FV box.

In the event of a specific issue, members of the personnel should contact their local SIP.

3.3 Other income

For specific questions about how to fill in the various sections of the form to take into account any other income and individual circumstances, members of the personnel are invited to refer to the notes sent out with the tax declaration form (or available from the Ministry of Economy and Finance’s tax administration website) or to contact their local SIP directly. Useful information is also available in the document prepared by the Valserhône SIP.

Users and associates receiving other income must also read section 4.1.

3.4 Foreign bank accounts

Foreign bank accounts (i.e. located outside France), including those into which any financial or family benefits are paid, must be declared. This declaration must be renewed every year (cf. point 4 of the document prepared by the Valserhône SIP).

4. Special cases

4.1 Users and associates

  1. All Users and associates domiciled in France are obliged to complete an income declaration form. They are exempt from national taxation only on income from financial benefits paid by CERN and appearing on their internal taxation certificate. For these amounts, they must therefore follow the procedure outlined in part 3.1 above for that income.
  2. Their other sources of income (for example, remuneration paid by their home institutes) may be liable for tax in France and must therefore be declared to the local SIP, even if such income is taxable in the country of origin of the payment.
    • Income (for example, remuneration paid by home institutes) is usually subject to tax in the country of origin. In some cases, it may be subject to a double taxation agreement between France (the country of residence) and the country of origin, in which case it is taxed either in France or in the country of origin.
    • If they receive from an institute outside France remuneration that is already taxed abroad, they must state at the end of the online declaration under the section « Informations – Mention expresse » “Membre du personnel du CERN (utilisateur/associé  [User/associate, as appropriate]), de nationalité … [their nationality], rémunéré par … [paid by: name and address of their employer], imposable en … [taxable in: the country where they are liable for income tax]”. If they use a paper version of the declaration, the same mention must be added on page 2 under the section “Informations” or on a separate sheet of paper if that section is already pre-filled in.
  3. The individuals concerned are invited to contact their local SIP regarding any specific issues relating to their declaration obligations.      

4.2 Members of the personnel of Swiss nationality resident in France

Swiss members of the personnel who are resident of France must complete the income tax declaration (cf. above information).

Those retaining a financial link with Switzerland (for example, if they own property in a canton) must also complete and return the Swiss income tax declaration form as described in the Income tax declaration in Switzerland procedure.

4.3 US citizens and Green-Card holders

CERN is not able to provide advice on these very specific situations and invites the members of the personnel concerned to contact their local SIP and/or the US consular authorities. They may also refer to the FAQ prepared by the Valserhône SIP.

5. Tax assessment notice

Members of the personnel who opt for the "paperless" option will receive an e-mail at the address indicated in their personal account as soon as their tax assessment notice is available. They will be able to consult it, download it and print it if necessary.

Members of the personnel who have not chosen the "paperless" option and who are domiciled in France receive, following their declaration, a document entitled “Avis d’impôt – Impôt sur les revenus”. This document must not be returned to the SIP. Members of the personnel must keep it, however, as the French authorities may ask them to produce it as evidence of their tax situation in France.
Further information may be obtained directly from the local SIP.

6. Housing and residence taxes in France

The Organization is not authorised to provide information on this type of tax. Members of the personnel are invited to contact a tax adviser ("fiduciaire") or relevant national tax authorities for more information.

Further information is available on the website

Nevertheless the French tax authorities would like to remind members of the personnel residing in France, that if they are eligible for residence and housing taxes ("taxe d’habitation" and/or "taxe foncière") and hold a French bank account, they may opt for monthly payments, direct debit of the full amount when payment is due or online payment for both these taxes. An application form can be obtained directly from the local tax office.


    No revision Modifications Approved
    1 Taxes procedure revised by the Legal Service following the public meeting that took place on 19 March 2014 with representatives of the Bellegarde SIP. 02.04.2014 
    2 "Informations" section replaces "renseignements complémentaires" in the declaration form. 25.04.2016
    3 Choice between paper and online declaration 26.04.2016
    4 Update of the Questions and Answers document prepared by the Bellegarde SIP 09.05.2016
    5 The deadline for submitting a declaration form on paper is Wednesday, 17 May 2017 06.04.2017
    6 The deadline for submitting a declaration form on paper is Thursday, 17 May 2018 ;
    Update of the Questions and Answers document prepared by the Bellegarde SIP
    7 A new approach to the annual internal tax certificates will be introduced as of 2020 for MPAs. 05.03.2019
    8 Update of the deadlines for submitting the paper form and online declaration and introduction of the online declaration. 16.04.2019
    9 Change of paragraph 2.1 Income received from  CERN following the new declaration for 2018 revenues. 18.04.2019
    10 Change in the conditions of declaration. 02.12.2019
    11 Bellegarde s/ Valserine SIP renamed to Valserhône SIP - procedure + FAQ update 07.01.2020
    12 Following exchanges with host state authorities and audit recommendations, the definition of financial benefits shall be limited, for associated members of personnel, to subsistence allowances paid on a statutory or contractual basis. 05.03.2020
    13 New deadlines tax return in light of the COVID-19 01.04.2020
    14 Update following re-issuing internal tax certificates to MPA that received financial certificate in February 2020. 29.04.2020