Abstract Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of Bacillus velezensis DSM 15544 (Calsporin®) when used as a feed additive for piglets (suckling and weaned), pigs for fattening, sows in order to have benefit in piglets, ornamental fish, dogs and all avian species. The additive is authorised for use in sows, suckling and weaned piglets, pigs for fattening, chickens for fattening, laying hens, ornamental fish and dogs. With this application the company requested a new authorisation for all avian species and the modification of the current authorisations as regards the strain taxonomy from Bacillus subtilis DSM 15544 to B. velezensis DSM 15544. The FEEDAP Panel concluded that the active agent of Calsporin® should be taxonomically designated as Bacillus velezensis DSM 15544. The Panel also concluded that Calsporin® is presumed safe for the target species, consumers and the environment. Calsporin® is not a dermal/eye irritant or a skin sensitiser but should be considered a respiratory sensitiser. Calsporin® when supplemented at 3 × 108 CFU/kg complete feed has the potential to be efficacious in all avian species for rearing, fattening, laying and breeding purposes.