C3S Taxe 2025: The Hidden Corporate Charge No one Can Ignore!

What Is the C3S Taxe?

The Contribution Sociale de Solidarité des Sociétés (C3S taxe) is a corporate social solidarity contribution applied to businesses in France whose annual turnover exceeds €19 million (excluding VAT). Collected and monitored by Urssaf Provence-Alpes-Côte d’Azur, this employer-funded tax plays a key role in financing the French retirement insurance system.

To learn more about related tax obligations, read our complete guide to the taxe PUMA.

Explore official Urssaf information on C3S taxe

Which Companies Must Pay the C3S Taxe?

You are liable for it if:

Your business or company is active as of January 1 of the year for which the contribution is due.
Your turnover exceeds €19 million (excluding VAT).

If your business does not meet both criteria, you are exempt and do not need to declare the contribution. The tax authorities provide your turnover information to the C3S managing body, which may contact you for additional details if necessary.

Certain companies may be exempt and must submit relevant supporting documents, including the exemption case number and copies of their statutes.

To see the full list of companies liable or exempt from it, consult the official notice.

How the C3S Taxe Is Calculated

The base for calculating it includes turnover that falls under the scope of VAT, whether subject to it or exempt.

This figure is determined exclusive of VAT and similar taxes. Amounts covered under the French General Tax Code (Book I, Part 1, Title II and Part 2, Title III, Chapter I bis) are excluded from this calculation.

The rate of it is fixed at 0.16%.

For in-depth calculation rules, consult the official notice.

C3S Taxe Declaration Process

If your company’s annual turnover (excluding VAT) exceeds €19 million, you must declare and pay the C3S taxe in the year following that threshold being reached.

All declarations and payments must be completed online via net-entreprises.fr no later than May 15.

If you haven’t registered yet on net-entreprises.fr, do so promptly to access the declaration portal. Already registered? Double-check and update your submitted data as needed.

For 2025, the C3S taxe e-declaration service opened in early March.

Important

If your business undergoes changes (e.g., merger, legal status changes, liquidation), specific declaration procedures apply. Consult the official notice for more details.

C3S Taxe Payment Instructions

Payment must be made exclusively by SEPA direct debit (télérèglement).

Manage your company’s bank details and mandates via your dashboard on net-entreprises.fr under “Vos coordonnées bancaires.”

⚠️ A mandate is considered void if unused for 36 months from the date of the last SEPA transaction.

Note

Mandate validation alone doesn’t confirm payment. You must explicitly initiate the payment via télérèglement.

After submitting your declaration, you may complete the payment immediately or return later via the dashboard.

The direct debit will be processed on the official due date of the C3S taxe.

For help with registration, payment setup, navigation, or technical issues on net-entreprises.fr, contact their support line: 0 806 800 700 (toll-free + call cost).

Failure to Declare or Pay

If you fail to declare your turnover, the C3S management body may estimate it based on available public data or annual accounts.

Failure to meet all declaration and payment requirements may result in penalties.

The Declaration and Control System of the C3S Taxe

The C3S taxe relies on a self-declaration system based on mutual trust. In return, Urssaf Provence-Alpes-Côte d’Azur, as the managing body, may conduct audits to verify the accuracy of your declarations.

These audits are conducted remotely through electronic and postal communication.

To learn more about C3S audits, refer to the official control charter document.