We report the use of bacteriophages for control of Salmonella Enteritidis in poultry production. Phage was isolated by the double-agar plate assay from agricultural waste samples, and one isolate, named SM1, was selected and propagated for application in poultry litter. Two experimental protocols were tested: single treatment and repeated treatment (re-application of phage SM1 after 6 h and 12 h). Each treatment cycle involved 25 g of poultry litter placed in plastic boxes and contaminated with 105 Colony Forming Units mL−1 (CFU mL−1) of S. Enteritidis, in independent duplicates. The contaminated litter was treated with 106 Plaque Forming Units mL−1 (PFU mL−1) of SM1 phage by dripping. Repeated application of phage SM1 reduced Salmonella counts by over 99.9%; the phage persisted in poultry litter for over 35 days. This study illustrates the application of SM1 treatment as a promising technology for bacterial control in production matrices that could allow safe and sustainable use of agricultural waste products as biofertilizers.