Abstract Background Every cold season, the Italian health institutions strongly recommend influenza vaccination for categories at risk of complications, however influenza vaccination coverage is over and over far from the desirable target of 95%. After the pilot experience conducted in Palermo during the 2022-23 influenza season, the ‘Vaccinations in the ward’ project was extended to other Sicilian centers in order to evaluate the impact of the vaccination offer strategy in a broader territorial reality and to analyze the determinants of influenza vaccine acceptance among at risk people. Methods The project was conducted at the Umberto I Hospital in Enna and the University Hospitals of Messina and Palermo during the 2023-24 influenza season. A questionnaire was administered to the at risk hospitalized patients to investigate socio-demographic factors, behavioral habits, and clinical condition. Furthermore, influenza vaccination upon discharge was offered. Multivariable logistic regression was performed to identify the determinants of influenza vaccine acceptance. Results Overall, 374 patients with a median age of 65 years (IQR: 50-70) were recruited, of whom 36% had been vaccinated for influenza during the 2022-23 season (n = 136). The patients who accepted influenza vaccination in the ward were 57% (n = 214). The determinants of vaccination adherence were: age (OR: 1.03; p = 0.003); having quit smoking (OR: 2.68; p = 0.017); having received advice on vaccination from general practitioner (OR: 4.9; p < 0.001) and hospital healthcare workers (OR: 7.3; p < 0.001). Conclusions The offer of vaccination in the ward effectively increased influenza coverage among categories at risk of complications. Furthermore, the adoption of correct behavioral habits and the promotion of influenza vaccination by healthcare personnel have played a decisive role in the vaccine acceptance process. These findings could be useful for planning future influenza vaccination campaigns targeted to at risk people. Key messages • Vaccination strategies are needed to increase influenza coverage among at-risk categories. Active offer of influenza vaccine upon discharge can effectively increase vaccination compliance. • The adoption of correct behavioral habits and the promotion of vaccination by healthcare personnel play a decisive role in the influenza vaccine acceptance process among at risk people.