OBJECTIVES: Pan-European surveillance databases allow for comparisons of influenza epidemic characteristics between seasons using descriptive time-series analysis. We explored the use of data from The European Surveillance System (TESSy) and Influenzanet (internet based) to describe influenza epidemiology in Europe. METHODS: We obtained influenza-like illness (ILI) data from TESSy (seasons 2001/2 to 2014/15) and Influenzanet (seasons 2003/4 to 2014/15). Data available from all countries were pooled for the analysis for each data source separately. We estimated the intensity of influenza circulation (frequency of ILI/10000 consultations per calendar week) for both databases. RESULTS: There were 7.4 million and 24,000 ILI cases reported respectively through TESSy and Influenzanet during the study period. The weekly average population denominator was 34 million in TESSy and 18,000 in Influenzanet. TESSy covers 30 countries while Influenzanet covers 9. We found TESSy and Influenzanet to be complementary data sources. TESSy captures only medically attended influenza while Influenzanet captures also non-medically attended influenza. The two databases provided a rather consistent picture of flu intensity across the continent over the different seasons despite the differences in geographical coverage. Their main strengths are coverage of a large population and consistent reporting over time. Influenzanet results showed the best comparison and standardization between countries. The incomplete documentation of data sources in TESSy which makes it difficult to evaluate representativeness of the data and the impact of changes over time and the different levels of “updateness” with the latest season data are the main limitations to the use of these databases. CONCLUSIONS: Combining multiple influenza surveillance data streams can provide a more complete picture of the epidemiology and burden of influenza in Europe over long time periods. Strengths of TESSy and Influenzanet are: coverage of large population, consistent reporting over time, and complementarity of information sources between general public and healthcare professionals.