The Nominative Social Declaration (Déclaration Sociale Nominative, DSN), rolled out across the board since 1 January 2019, is a mandatory formality for all companies employing staff in France. Previously, companies sent an annual declaration (the DADS-U) to each social body (Pôle emploi, CPAM, Urssaf and so on). The process is now monthly and unified: a single declaration automatically transmitted to all the bodies, containing all the information relating to your employees and their social entitlements. Here is how to set it up properly in 2026.
What must be declared with the DSN?
Two main types of information pass through the DSN:
- Monthly payroll data: pay paid out and the corresponding social contributions, entered once the payslips have been generated.
- Exceptional events: sick leave, accident at work, maternity leave, end of contract and so on, which are subject to a specific notification.
To avoid a rejection, your DSN file must in particular include the amount of pay and contributions shown on the payslips, your company’s SIRET number, each employee’s social security number, and the references of the group health insurance, death and disability, and supplementary pension contracts.
Point to watch: it is common for insurers not to find your declarations because of a data-entry error in the contract references. A double check saves you unnecessary steps and processing delays. To make this configuration reliable over the long term, see our dedicated article on DSN best practices.
When should you file your declaration?
The deadline depends on your headcount:
- Fewer than 50 employees: declaration before the 15th of the month following the pay period.
- 50 employees or more: declaration before the 5th of the month.
- Event notification (work stoppage, end of contract and so on): within 5 days following the event.
Failure to meet these deadlines exposes you to penalties. As the DSN is mandatory, financial penalties apply in the event of late filing, omission or failure to declare, calculated per employee and per month. The details of the amounts are set out on Service-Public.fr.
How to file your DSNs?
If your company falls under the general scheme:
- Create your account on net-entreprises.fr, the official portal for social declarations.
- File your monthly declaration, either online by uploading a file on net-entreprises, or directly from your payroll software compatible with the NEODeS standard, if it has been configured beforehand.
Each year, remember to import into your software the Configuration Sheets for Supplementary Organisations (Fiches de Paramétrage des Organismes Complémentaires, FPOC) sent by your health, death and disability, and pension insurers.
If your company falls under the agricultural scheme: the process is carried out on the portal of the Agricultural Social Mutuality (Mutualité Sociale Agricole, MSA).
And then?
Once sent, your data is checked and then transmitted to the social bodies. In return, you receive a certificate of compliance if the DSN is validated, or an anomaly report if it is rejected, in which case the file must be corrected and resent.
The DSN was designed to save time for HR departments and social bodies, reduce data-entry errors, combat fraud and make it easier for employees to access social benefits. Today, it has replaced nearly 80 separate declaration formalities.
An alternative for small structures: the Tese
Some companies do not wish to manage the DSN themselves. VSEs with fewer than 20 employees can then use the Business Employment Service Voucher (Titre Emploi Service Entreprise, Tese), a free Urssaf service that handles the DPAE, the simplified contract, the payslips and the DSN in a single step.
A new feature to know about: since 1 January 2026, it is possible to use the Tese for only some of your employees, while entrusting the others to a third-party declarant such as a chartered accountant.
How MIA can help
The DSN directly reflects your social protection contracts: one incorrect reference or one poorly configured contract, and the entire processing is blocked. As a specialist insurance broker, MIA Assurances supports VSEs, SMEs, mid-cap companies and foreign companies established in France in setting up and monitoring their health, death and disability, and pension benefits, working closely with your payroll department or your chartered accountant.
