This article examines the new provisions on contract interpretation and characterisation in Book 5 of the Belgian Civil Code, which entered into force on 1 January 2023. The reform preserves Belgium’s traditional subjective approach to interpretation, prioritising the parties’ common intention over literal textual meaning, contrasting with the objective or mixed approaches adopted by French law and international instruments. Regarding characterisation, Belgium introduces innovative provisions explicitly addressing contract classification and mixed contracts, filling gaps left by other legal systems. These aspects of the Belgian reform are put intto perspective with comparative observations drawn mostly from French, German, and Dutch law.