AIMS: To describe the analysis, epidemiology and control of six contemporaneous and linked outbreaks of Salmonella enterica subsp. enterica serovar Infantis on British broiler farms. S. Infantis is a potentially multidrug-resistant foodborne zoonosis and can persistently colonise poultry flocks and farms. METHODS AND RESULTS: Routine monitoring initially identified the organism, which was tracked to six farms associated with a single company. Extensive, repeat sampling identified wide-spread and in some cases persistent contamination. S. Infantis was also isolated from three associated processing factories and catching crew equipment, but not from associated hatcheries and feed mills. Whole genome sequencing and resistance phenotyping revealed one strain was present in the processing plants and on five farms. However, on one of those farms several highly genetically distinct strains were also detected, including one also found in one of the processing plants. The sixth farm had a strain that was genetically unrelated to strains collected from the other premises and which exhibited an extended spectrum beta-lactamase phenotype. Cleaning and disinfection were enhanced, and the organism was eventually cleared from all farms. CONCLUSIONS: There were multiple incursions of varied strains, with a possible link to processing factories. Elimination of S. Infantis from premises can be challenging but achievable.