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 perform their professional activities, whether in receipt of a salary or not, in France, unless they can prove that the activity performed in France is secondary; or
• if they have the centre of their economic interests in France.

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

2. When to file an income tax declaration

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

• 25 May 2023 for departments 01 to 19,
• 01 June 2023 for departments 20 to 54,
• 08 June 2023 for departments 55 to 976.

The deadline for submitting paper declarations is set at 22 May 2023, based on the date of the postmark (including for non-residents in France required to file a declaration).

The online income tax declaration is mandatory for everyone. Members of the personnel are notified of the opening of the online service via the e-mail address they have indicated in their personal account, and are able to complete their income tax declaration when the online service is opened.

Only persons who are technically or otherwise unable to complete an online form may continue to submit a paper form.

In such cases, they 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 (Service des impôts des particuliers) or its local branch in Gex.

3. How to complete the declaration form

3.1 Member of the personnel receiving an internal tax annual 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 tax annual 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. It is compulsory for them to tick boxes 8FV and 8UU (if bank account abroad outside France), in Part 8 "Divers" of the paper form. On the online declaration, this part is accessible in step 3 "Revenus et charges" under the heading "Divers", by ticking the box entitled "Comptes à l'étranger, revenus de source étrangère, reprise de réductions ou de crédit d'impôt ".
3. They must enter 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 financial and family benefits paid by CERN). On the online version, the note must be entered at the end of the form under the heading “Informations ” by ticking the box. 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 tax annual certificate
   - is to be sent via the secure messaging service by connecting to the "espace particulier" on the site www.impots.gouv.fr,
   - 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 Member of the personnel receiving an individual annual statement

Members of the personnel who have received an individual annual statement from the CERN administration 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 amount of salary and other income that is likely to be subject to tax in the home country; this includes cost-of-living allowance if it is subject to tax in the home country;
2. Under the heading "autres salaires imposables de source étrangère" (box 1AG): report the amount of salary and other income that is not likely to be subject to tax in the home country; this includes cost-of-living allowance if it is not subject to tax in the home country; deduct from those amounts the premium paid for a compulsory health insurance scheme.
3. If the cost-of-living 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. The option for deduction is up to the person: either a flat rate of 10% (applied by the fiscal authority) or real expenses. These costs may include journey expenses between place of residence and workplace, additional meal expenses, contribution to trade unions and insurance premiums for professional liability, professional training expenses, and costs associated with dual residency situation (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, with the condition that is justified the obligation for the member of personnel to reside in a different location than the usual place of residence of their partner / spouse). 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.
4. The individual annual statement
   - is to be sent via the secure messaging service by connecting to the "espace particulier" on the site www.impots.gouv.fr,
   - 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.

Very important: Members of the personnel who use an individual annual statement must not tick the 8FV box.

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

3.3 Associated member of the personnel receiving neither financial and family benefits paid by CERN, nor cost of living allowance

Associated members of the personnel receiving neither financial and family benefits paid by CERN, nor cost of living allowance may be liable for tax in France on other sources of income (for example, remuneration paid by their home institutes) and must therefore be declared to the local SIP, even if such income is taxable in the country of origin of the payment.

1. 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.
2. If they receive from an institute outside France remuneration that is already taxed abroad, they must enter 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.

The individuals concerned are invited to contact their local SIP regarding any specific issues relating to their declaration obligations.

3.4 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 3.3.

3.5 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 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.

4.2 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 an online declaration 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 have filled in a paper declaration and who are domiciled in France receive by post mail, 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 www.impots.gouv.fr and on the FAQ prepared by the Valserhône SIP (see point 3.3).

As of 2023, households are not subject to residence tax for their primary residence, which is determined according to the address indicated on their income declaration (address on 1 January of the fiscal year concerned).

Residence tax still applies to secondary residences and vacant properties (see article on CERN bulletin).