Background: Influenza is a major cause of respiratory illness in young children. Assessing the impact of infection on children and the community is required to guide immunisation policies. Objectives: To describe the impact of laboratory-proven influenza in young children and to compare its impact with that of other respiratory viruses on the child, their family and the health care system. Methods: Preschool children presenting for care or admission to a tertiary paediatric hospital during the 2008-2014 influenza seasons were tested for respiratory virus by polymerase chain reaction and culture. Parental surveys were used to determine the impact of infection on illness duration, medication use, absenteeism and health service utilisation. Multivariate regression analyses were used to assess the impact of influenza and to evaluate the association between influenza status and outcomes. Results: Among 1191 children assessed, 238 had influenza. Among children with influenza, 87.8% were administered antipyretics and 40.9% antibiotics. 28.6% had secondary complications. 65.4% of children missed school/day care, and 53.4% of parents missed work. When influenza and other viruses were compared, significant differences were noted including duration of illness (influenza: 9.54 days, other viruses: 8.50 days; P = 0.005) and duration of absenteeism for both the child (23.1 vs 17.3 hours; P = 0.015) and their parents (28.5 vs 22.7 hours; P = 0.012). Conclusions: Influenza infection in young children has a significant impact on medication use, absenteeism and the use of health care service. Significant differences are identified when compared with other ILI. These data demonstrate that influenza prevention strategies including immunisation are likely to have wide and significant impacts.