Following a request from the European Commission, the EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS) provides a scientific opinion regarding the safety of the extension of use of the food additive sucralose (E 955) when added to dietary food for special medical purpose (FSMP) intended for young children aged from 1 to 3 years. Sucralose was evaluated by the EU Scientific Committee on Food (SCF) who established an acceptable daily intake (ADI) of 15 mg/kg body weight (bw). Sucralose is authorised in the EU for food use with exception for foods for young children. According to the applicant, the use of sweeteners is required to ensure palatable foods for the dietary management of patients whose compliance with the dietary regime (prescribed by healthcare professionals) is a key factor to their health. The exposure scenarios based on the proposed use by the applicant on the FSMP indicated that the total daily protein requirement (3 g protein/kg bw) could be covered by the product containing 400 mg sucralose/kg without exceeding the ADI. Also, exposure in other scenarios based on different assumptions was always below the ADI. Therefore, the ANS Panel concluded that the proposed extension of use of sucralose (E 955) in FSMP in young children aged from 1 to 3 years would not be of safety concern.