Eight localities of Kalanchoe laxiflora and fifteen localities of K. ×houghtonii were recorded in northeastern Algeria, resulting from field surveys carried out in the wilayas (regions) of Skikda, Annaba, El Tarf, and Souk Ahras. Kalanchoe laxiflora is here reported for the first time from Algeria and for the second time from mainland North Africa. Kalanchoe ×houghtonii was recorded in Algeria before. Here we report additional occurrences in four wilayas. The substrate preferences, especially in human-made habitats, naturalisation status and future spread of the two taxa, are discussed.