A classification for primary and incisional abdominal wall hernias was developed through a consensus meeting of experts from the European Hernia Society (EHS). The goal was to enable comparison of studies and improve the quality of reporting in hernia surgery. The classification focuses on the localization and size of hernias, with separate categories for primary and incisional hernias. For primary hernias, localization (epigastric, umbilical, Spighelian, lumbar) and size (small, medium, large) are used. Incisional hernias are classified by localization into midline (M1–M5) and lateral (L1–L4) zones, with size measured by the width of the hernia defect (W1–W3). The classification includes a grid format for easier use, though the exact size variable remains debated. The classification aims to standardize data collection and improve the comparison of surgical outcomes. While a complete grid format for incisional hernias could not be finalized due to disagreements on size variables, a simplified classification is proposed. This classification may help in establishing hernia registries and comparing treatment outcomes. The classification is considered essential for improving the quality of reporting in hernia surgery.A classification for primary and incisional abdominal wall hernias was developed through a consensus meeting of experts from the European Hernia Society (EHS). The goal was to enable comparison of studies and improve the quality of reporting in hernia surgery. The classification focuses on the localization and size of hernias, with separate categories for primary and incisional hernias. For primary hernias, localization (epigastric, umbilical, Spighelian, lumbar) and size (small, medium, large) are used. Incisional hernias are classified by localization into midline (M1–M5) and lateral (L1–L4) zones, with size measured by the width of the hernia defect (W1–W3). The classification includes a grid format for easier use, though the exact size variable remains debated. The classification aims to standardize data collection and improve the comparison of surgical outcomes. While a complete grid format for incisional hernias could not be finalized due to disagreements on size variables, a simplified classification is proposed. This classification may help in establishing hernia registries and comparing treatment outcomes. The classification is considered essential for improving the quality of reporting in hernia surgery.