Average headcount (social-security rules)

Sources and assumptions

• entreprendre.service-public.gouv.fr — F24332 — tax year 2026, verified on September 17, 2026

  Excerpt from the source : « L'équivalent temps plein (ETP) est calculé à partir de la durée mensuelle légale de travail, égale à 151,67 heures par mois. »

• entreprendre.service-public.gouv.fr — F24332 — tax year 2026, verified on September 17, 2026

  Excerpt from the source : « Le chiffre est arrondi au centième inférieur, soit 2 chiffres après la virgule. »

• entreprendre.service-public.gouv.fr — F31415 — tax year 2026, verified on September 17, 2026

  Excerpt from the source : « Pour l’effectif « sécurité sociale », les effets liés au franchissement d’un seuil ne s’appliquent qu’après 5 années consécutives de dépassement. Les nouvelles obligations s’appliquent donc à partir de la sixième année si le seuil a été maintenu durant toute cette période. »

• entreprendre.service-public.gouv.fr — F31415 — tax year 2026, verified on September 17, 2026

  Excerpt from the source : « Contribution à la formation professionnelle (CFP) au taux de 1 % après 5 ans consécutifs avec un effectif de 11 salariés ou plus »

• entreprendre.service-public.gouv.fr — F31415 — tax year 2026, verified on September 17, 2026

  Excerpt from the source : « L’entreprise est soumise à l’obligation d’emploi des travailleurs handicapés après 5 ans consécutifs avec un effectif de 20 salariés ou plus »

• entreprendre.service-public.gouv.fr — F31415 — tax year 2026, verified on September 17, 2026

  Excerpt from the source : « Contribution FNAL (Fonds national d'aide au logement) au taux de 0,50 % sur la totalité des rémunérations brutes, après 5 ans consécutifs avec un effectif de 50 salariés ou plus »

• entreprendre.service-public.gouv.fr — F31415 — tax year 2026, verified on September 17, 2026

  Excerpt from the source : « Taxe d’apprentissage et, à partir de 250 salariés, la contribution supplémentaire à l'apprentissage (CSA) »

Calculation assumptions

• Only the social-security headcount (CSS art. L130-1) is computed: the one that governs the training contribution, the FNAL housing levy, the versement mobilité transport levy, the forfait social, statutory profit-sharing and AT/MP occupational-risk rating. The labour-code headcount, which governs the works council (CSE), the internal rules and the BDESE database, follows different rules — it prorates fixed-term, temporary-agency and seconded staff over the preceding twelve months.
• The input describes a permanent workforce, stable across the months actually staffed, plus a single temporary contingent. A year with more than two headcount tiers cannot be entered as such: the sum of monthly headcounts must then be rebuilt by hand. Months are whole: a start or departure during a month, which the official rule prorates by calendar days, is not represented. Part-timers' hours are divided by the statutory monthly working time; a company whose collectively agreed working time is shorter must divide by that agreed duration instead, which the calculator does not do. The official figure remains the one Urssaf computes from the nominative social declaration (DSN).
• The result is truncated to two decimals. The official page labels its rule "rounded down to the nearest hundredth" under one example and "rounded to the nearest hundredth" under another, while both printed results truncate (118.86 / 12 shown as 9.90; 106 / 6 shown as 17.66): the results are followed, not the labels. Intermediate prorations are not rounded — the page rounds one to the nearest and the other down within a single table.
• Not modelled: multi-firm sales representatives (VRP multicarte), counted in proportion to their pay over the monthly minimum wage; intermittent permanent contracts, counted only over their active phases; employer groupings and temporary-work agencies, where seconded staff remain counted; the farming scheme (MSA).
• One threshold is followed at a time, and the number of consecutive years above it is entered, never reconstructed: the calculator only knows the year being counted. An entry claiming zero consecutive years while the counted year is itself above the threshold is corrected to one, and says so. The year of effect follows each scheme's reference period: the headcount computed from one year's data counts for the following year under the general rule (11- and 50-employee thresholds), and for that same year for the obligation to employ disabled workers and the additional apprenticeship contribution (20- and 250-employee thresholds).