Abstract This article describes the development of a free/open-source morphological description of Maltese, originally created as the analysis component in a rule-based machine translation system for Maltese to Arabic and later applied to other tasks. The lexicon formalism we use is lttoolbox, part of the Apertium machine translation platform. An evaluation of the analyser shows that the coverage is adequate, at 84.90%, while precision is 92.5% on a large automatically annotated test set and 96.2% on a smaller hand-validated set.