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Unified Annual Social Data Declaration (UDAD)

Verified 02 July 2020 - Directorate for Legal and Administrative Information (Prime Minister)

The Nominal Social Declaration (DSN) replaces the Unified Annual Social Data Declaration (UDAD) in most companies. However, a number of employers must continue to complete the U-DADS.

Employers who are required to file a Unified Annual Social Data Return (UDAR) are:

  • Employers who complete the social declaration nominative (DSN) but employ populations outside DSN boundaries. Examples: fishermen, dockers, officials on secondment to a private establishment.
  • Public service employers
  • Institutions completing the NSD that could not transmit data from complementary bodies (CBs) in the DSN.


all other employers must perform a registered social declaration (DSN)..

In the event of a delay, omission or inaccuracy of the reported data, the employer risks the payment of a penalty equal to €51 per employee up to €750 by declaration.

If the delay exceeds 1 month, an identical penalty shall be applied for each month or fraction of a month of delay.

The U-DADS must contain the following elements:

  • Identification of employer and employee 
  • Characteristics of employment and employment contract 
  • Period of employment 
  • Earnings received in the previous year 
  • Contributions (and contribution bases) used for entitlement to old-age and health insurance.

The U.S. DADS must list one of the following 3 reasons for filing:

  1. EX: DSN-filling employer with populations excluded from DSN perimeter
  2. NO: employer not subject to the obligation to fulfill the DSN
  3. OC: employer who did not transmit the data OC (complementary bodies) in DSN

A company that has payroll software that complies with 4DS (electronic data interchange) "EDI") must file the U-DADS online:

Unified Automated Social Data Reporting (UDAD)

An employer who does not have payroll software must do the DADS-U on

DADSNET - DADS-U Online Declaration

The DADS-U can be carried out directly with complementary health bodies such as, for example, mutuals, insurance,Agirc-Arrco: titleContent,Ircantec: titleContent, CNRACL: titleContentpension funds.

At the same time as the DADS-U, the employer must send to the Urssaf a summary table of contributions (TR), which must include the following information:

  • Gross remuneration of all employees of the institution paid in the previous calendar year
  • Contributions and contributions due
  • Overall workforce at 31 December
  • Average strength as at 31 December

The TR is pre-filled and searchable online when the last one is saved summary statement of social security contributions (BRC)..


If you do not report through the NSB, you have until January 31 of year N+1 to submit your summary of contributions (TR) for year N.

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