Cerfa 12504: Apply for the C2S (Complémentaire Santé)

What is Cerfa 12504 - Complémentaire santé solidaire (C2S)?

The Complémentaire santé solidaire (C2S) is France's top-up health cover for people on modest incomes. It replaced the CMU-C and the ACS in 2019. The notice on the form says that with it you no longer pay your health costs at the doctor, dentist, pharmacy or hospital, doctors can't charge you more than the standard fees, and most glasses, dentures and hearing aids are fully covered. Depending on your resources it is free, or costs a monthly contribution that depends on each person's age.

Cerfa 12504*14 (S 3711o) is the application. One form covers the whole household: you, your spouse or partner, and the people under 25 you support. Page 1 lists the household and who gets the RSA, AAH, ASPA, ASI, ASS or ACEJ. Page 2 is the household's resources over 12 months, in a column per person. Pages 3 and 4 are where you choose who manages your C2S (your health insurance fund, or a mutual insurer or other organisation on the official list) and give its details. Then you sign. Pages 5 and 6 are the notice.

FileIt asks the questions in plain English, shows only the people and columns you need, checks the key of every social security number, and follows the form's chart for choosing the organisation. It prints names in capitals as the form asks, including Polish, Romanian and other accents, and writes each euro amount right-aligned in its boxes. The filled PDF is saved in your vault. You sign it and send it to your fund yourself. FileIt never submits anything.

Who fills it: A person covered by the French health insurance (PUMa) whose household resources are under the C2S ceiling
Given to: Your health insurance fund: the CPAM (or CGSS overseas), or the MSA for the farming scheme
Covers: The whole household: you, your spouse or partner, and dependants under 25
Signatures: The applicant signs page 4
Edition: cerfa N° 12504*14 (S 3711o), 4 pages plus a 2-page notice

Who needs to fill out Cerfa 12504 - Complémentaire santé solidaire (C2S)?

A household on a low or modest income that struggles with the part of health costs the Assurance Maladie doesn't pay.
People who get the RSA. The notice says they meet the income condition for the free C2S automatically.
People who get the ASPA, ASI, AAH, ASS or ACEJ, who may qualify for the C2S with a contribution without declaring their resources (see the notice).
Families whose CMU-C or old ACS has ended and who want the cover that replaced them.
A young adult under 25 who no longer lives with their parents and files their own tax return. The notice says they apply on their own.
Anyone renewing the C2S each year, since it is granted for a year at a time.

When to use Cerfa 12504 - Complémentaire santé solidaire (C2S)

When your household's income drops, for example after losing a job, a separation or a new baby.
Before your current C2S runs out, to renew it.
When you arrive in France and have just joined the health insurance (PUMa) with form S 1106a.
Whenever you would rather have the C2S than pay for a private mutuelle you can't afford.

What you need before you start

Social security numbers (with their keys) and dates of birth for everyone in the household, and CAF file numbers if you have them.
Your address, or the name and address of the organisation where you are registered if you have no personal address (élu domicile).
The resources of each person over the 12 calendar months from the 13th to the 2nd month before you apply. You can skip salaries and benefits that are reported to the fund directly.
Business turnover for the last four quarters if someone has just started a self-employed activity, or the pay of a company manager.
Whether anyone is on long sick leave, on unemployment benefit or the ASS, on a paid training course, or gets daily allowances, an invalidity pension, family benefits or housing aid.
Whether you own your home or are housed free of charge.
The name and address of the mutual insurer or other organisation on the list, if one will manage your C2S.
Your last tax notice (avis d'impôt or ASDIR) to enclose, and documents from abroad if you lived abroad during the period.

What’s on Cerfa 12504 - Complémentaire santé solidaire (C2S)

The 2026 edition has 6 pages. FileIt asks for it in 13 parts, and it is signed by Applicant:

La composition de votre foyer - vous-même (you)Applicant
Votre conjoint(e), concubin(e) ou partenaire de PACS (your partner)Applicant
Les autres personnes de moins de 25 ans à votre charge (dependants under 25)Applicant
Vous-même et les personnes de votre foyer bénéficiaires d'aides (benefits received)Applicant
Les ressources de votre foyer - période (household resources: the 12 months)Applicant
Les ressources de votre foyer - Vous - youApplicant
Les ressources de votre foyer - Votre conjoint(e) - your partnerApplicant
Les ressources de votre foyer - Enfant ou personne à charge de moins de 25 ans (1st column)Applicant
Les ressources de votre foyer - Enfant ou personne à charge de moins de 25 ans (2nd column)Applicant
Le choix de votre organisme complémentaire (who manages your C2S)Applicant
3 Personnes du foyer ayant choisi le même organisme (household members with the same organisation)Applicant
4 Vos coordonnées (the contact person for the organisation)Applicant
Attestation sur l'honneur et signature (declaration)Applicant

How to fill out Cerfa 12504 - Complémentaire santé solidaire (C2S), step by step

1 Vous-même and your partner

Your name, social security number, CAF file number, date of birth, nationality and address, and whether your family situation changed in the last 12 months. Then the same details for your spouse, cohabiting partner or PACS partner, if you have one.

2 Dependants under 25

Up to six people under 25 you support, with nationality as a code (FRA, EEE or AUT), relationship, shared custody, date of birth and social security number.

3 Benefits received

For up to five people, whether they have applied for or already get the RSA, and whether they get the AAH, ASPA or ASV, ASI, ASS or ACEJ.

4 Les ressources de votre foyer

First the 12-month period. Then, for you, your partner and up to two dependants with their own resources, the amounts in whole euros (0 where there is nothing) and the yes/no questions: sick leave, unemployment, ASS, training pay, daily allowances or pensions, family benefits or housing aid, owning your home or being housed free of charge, and other resources with their nature.

5 Le choix de votre organisme

The chart on page 3. Do you have a top-up insurer now? Do you already have the C2S? Is your insurer on the official list? Depending on the answers, either your current insurer manages the C2S, or you choose between an organisation on the list and your health insurance fund. If you choose nothing, the fund is designated.

6 Tables 3 and 4

Only when an organisation on the list manages the C2S: the household members who chose it (including you), and the contact details of the person it should get in touch with.

7 Signature

Write the place and date and sign. You certify on your honour that you have read the information on the form and that what you declared is accurate. The 'Droits à la C2S' block is filled in by the fund.

Common mistakes to avoid

Leaving resource boxes empty. The form asks for 0 where there is nothing.
Using the wrong 12 months. The period ends with the second month before the month you apply in.
Declaring salaries and benefits that are already reported to the fund, when the notice says you need not.
Choosing a mutual insurer that is not on the official list at complementaire-sante-solidaire.gouv.fr.
Not choosing your current insurer when it is on the list and this is your first C2S application. The form says you must choose it.
Forgetting the social security number key, or mixing up a child's number with a parent's.
Forgetting to enclose the tax notice (avis d'impôt or ASDIR) for the household.

After you fill it out

Sign page 4 and add your last tax notice, plus documents from abroad if you lived abroad during the period.

Send it to your health insurance fund: the CPAM (or CGSS overseas), or the MSA. If an organisation on the list will manage your C2S, the fund passes pages 3 and 4 on to it, as the form says. FileIt does not send anything for you.

Keep the filled PDF in your FileIt vault and set a reminder for the renewal, so next year's application is quicker.

Fill out Cerfa 12504 - Complémentaire santé solidaire (C2S) online with FileIt

Pick the person. Choose someone from People and FileIt fills in their name, date of birth, address and other details it already knows.
Answer plain-language questions. One part of the form at a time, with the official help text beside each question — 238 fields in all. Your answers save as you go.
Check the live preview. Watch your answers land on the real Assurance Maladie / Ministère chargé de la Santé (via service-public.fr) form, and let FileIt do any worksheet arithmetic.
Generate the official PDF. FileIt prints your answers into the agency’s own PDF and files it in that person’s folder in your vault. Sign it, or send it for e-signature.

FileIt fills the form — it never files or submits anything for you. Deliver the finished form to whoever asked for it, the way the form’s instructions say.

Start Cerfa 12504 - Complémentaire santé solidaire (C2S) now — it’s free

Cerfa 12504 - Complémentaire santé solidaire (C2S): frequently asked questions

What is cerfa 12504?

Cerfa 12504*14 (S 3711o) is the application for the Complémentaire santé solidaire (C2S), the French top-up health cover for households on modest incomes. It is free or costs a small contribution, depending on your resources.

Is the C2S the same as the CMU-C?

The C2S replaced the CMU-C and the ACS (aide à la complémentaire santé) in 2019. Cerfa 12504 is now the form for it.

Do I declare my salary?

The notice says you don't need to declare salaries, replacement income or social benefits, because the organisations that pay them report them, nor income on your last tax notice. Page 2 is mostly for self-employed income, exceptional allowances, the yes/no situations and other resources.

Who manages my C2S?

You choose: your health insurance fund, or a mutual insurer, provident institution or insurance company on the official list. If you choose nothing, your fund is designated.

Can I fill in cerfa 12504 online with FileIt?

Yes. FileIt asks the questions in plain English, checks the social security numbers and follows the form's chart, then prints your answers into the official PDF, which is saved in your vault.

Where do I send it?

To your health insurance fund: the CPAM or CGSS, or the MSA if you are under the farming scheme. You send it yourself. FileIt never submits forms.

Does my 22-year-old apply with me?

It depends. The notice says a person under 25 applies on their own if they no longer live with their parents and file their own tax return, or if they live with you as a couple or have children of their own.

Official sources

Blank form (PDF), published by Assurance Maladie / Ministère chargé de la Santé (via service-public.fr): https://www.formulaires.service-public.gouv.fr/gf/cerfa_12504.do
Official instructions and guidance: https://www.service-public.gouv.fr/particuliers/vosdroits/F10027
Edition shown on this page: Cerfa N° 12504*14 (S 3711o) (checked 2026-10-19).

FileIt is not affiliated with or endorsed by Assurance Maladie / Ministère chargé de la Santé (via service-public.fr) or any government. This page explains the form in general terms and is not legal, tax or immigration advice. Always read the official instructions, and check that you are using the edition the recipient accepts. Page last reviewed 2026-10-19.