French Cerfa 2031 BIC Tax Return Filing Guide 2026

Any sole trader (entreprise individuelle) or partnership (société de personnes) carrying on a BIC activity and taxed under a real-income regime — either régime réel normal or régime réel simplifié — must file the 2031-SD. This includes artisans, traders, garage owners, and restaurateurs whose activity is commercially classified. Micro-entrepreneurs using the micro-BIC regime are specifically exempt and instead report their turnover directly on form 2042-C-PRO.

The key distinction is the tax regime of the entity. Form 2031-SD applies when business profits pass through the owner's personal income tax return (impôt sur le revenu). Form 2065 applies to companies subject to French corporation tax (impôt sur les sociétés — IS), such as a SARL or SAS that has not opted for the IR regime. Filing the wrong form can trigger penalties or a tax reassessment, so confirming your regime before filing is essential.

The 2031-SD must be filed with the complete liasse fiscale (annual tax return package). Under the régime réel normal, this means schedules 2050 through 2059, covering the balance sheet, profit-and-loss account, and fiscal adjustments. Under the régime réel simplifié, you attach schedules 2033 A through 2033 G instead. Both sets are mandatory — submitting the 2031-SD without the corresponding liasse fiscale is treated as an incomplete filing by the French tax authorities.

Once the 2031-SD establishes the taxable profit (bénéfice) or loss (déficit), that figure must be transferred onto supplementary form 2042-C-PRO — the personal income tax complement for self-employment income. For partnerships (sociétés de personnes), each partner individually reports their proportionate share (quote-part) on their own household's 2042-C-PRO. This two-step process links the business-level filing directly to the household income tax assessment.

Electronic transmission is mandatory for businesses on a real-income regime. You can file via EDI-TDFC (the professional electronic data interchange channel used by accountants and certified tax software) or directly through the espace professionnel section of impots.gouv.fr. Paper filing is no longer permitted. Your accountant or accounting software will typically handle EDI-TDFC transmission automatically, producing the required machine-readable file for the Direction Générale des Finances Publiques (DGFiP).

A professional BIC loss (déficit professionnel) declared on the 2031-SD can generally be offset against all other income categories in the same household's personal income tax return under Article 156 of the Code général des impôts (CGI). Non-professional BIC losses follow more restrictive rules and can only be carried forward against future income of the same category. Confirming whether your activity is classified as professional or non-professional is critical before applying any loss offset.