Introduction – This article presents an analysis of the epidemiological and virological characteristics of the influenza epidemic that occurred in mainland France during the 2024–25 season. Methods – The descriptive analysis focuses on clinical and virological data from the surveillance of acute respiratory infections, including outpatient visits for influenza-like illness, visits to emergency departments for influenza and influenza-like illness, virological data from hospital laboratories and private medical testing laboratories, and clinical data on severe influenza cases hospitalized in intensive care units. It also includes reports of acute respiratory infection episodes in long-term care facilities, including nursing homes, as well as mortality data—both all-cause and influenza-related—from electronic death certificates. Results – The influenza epidemic began in early December (Week 49, 2024), reached its peak of activity in the community in mid-January, and ended in late February (Week 8, 2025), lasting 12 weeks. Co-circulation of the three influenza viruses A(H1N1)pdm09, B/Victoria, and A(H3N2) was observed. The epidemic was characterized by very high intensity in community practice and hospitals, and across all age groups, with nearly 2 million outpatient visits and 30,000 hospitalizations following emergency department visits. There was a significant impact on long-term care facilities (approximately 2,000 reports of clustered influenza cases in long-term care facilities), as well as substantial excess mortality (approximately 17,600 deaths from all causes). Conclusion – The 2024–25 influenza epidemic was characterized by an early onset, a longer-than-average duration, atypical co-circulation of the three influenza viruses, and a significant impact on the healthcare system. It ranks among the most severe epidemics since the last influenza pandemic in 2009. It is important to emphasize the importance of implementing preventive measures to protect at-risk individuals, namely their own vaccination and that of healthcare professionals. This vaccination must be complemented by the adoption of preventive measures by everyone, in order to limit the spread of respiratory viruses within the population and reduce the impact of influenza on at-risk individuals and the healthcare system.