Recent epidemics have reminded us the importance of identifying gene functions to better fight against pathogens. In bacteria, researchers have traditionally used transposon mutant libraries to identify genes involved in various phenotypes such as bacterial survival, growth, or virulence. Recently, the use of TraDIS or Tn-seq methods made it possible to screen millions of mutants in a single experiment thanks to high-throughput sequencing. Moreover, saturation of the genome with transposon insertions allowed to detect even minor defects due to insertions into ORFs, intergenic- or promoter regions, and essential protein domains within coding sequences. In this study, we describe the construction and characterization of a saturated library using the Himar1 transposon in Salmonella Enteritidis, the most frequently isolated serotype of Salmonella during foodborne outbreaks. The library was generated in the S. Enteritidis LA5 virulent strain, a commonly used strain in research laboratories, by randomly inserting the transposon into TA dinucleotide sites throughout the genome. Sequencing of the library and subsequent analysis using the TRANSIT software demonstrated the saturation of the transposon mutant library both on the chromosome and the virulence plasmid and identified essential genes as well as those that confer advantages or disadvantages for bacterial growth in rich medium. The LA5 library is now being used in various research projects and is made available to the scientific community through collaborations.