Estimating the true number of COVID-19 cases can only be tentative at this early stage of the epidemic with data from a non-dedicated surveillance system. It is likely that the case definition of ILI does not allow identifying all COVID-19 cases. In addition, only a few cases were virologically tested, adding uncertainty in the estimates. Yet, the rate of excess ILI consultations applied to the French regions yielded a number of cases far in excess of confirmed cases, with 12,840 cases in IDF and around 10,000 cases in the regions GRE and HDF. Likewise, the extrapolated number of COVID-19 presenting as ARI was 760 in those older than 65 years in the two eastern regions (GRE and BFC): this was already twice the number of reported cases in these regions at the time (n = 379), all ages combined.