Voiceless geminate stops in Italian are typically described as unaspirated in all positions. However, recent acoustic phonetic analysis of part of a corpus of standard Italian speech data has shown that the geminate voiceless stops /pp tt kk/ are frequently realized with both preaspiration i.e. [hC] and post-aspiration. This paper focuses on the latter phenomenon, presenting acoustic phonetic evidence in the form of VOT duration values for /pp tt kk/ tokens recorded in 15 Italian cities (based on the CLIPS corpus of spoken Italian). The co-occurrence of post-aspiration with preaspiration is considered and results are discussed with a focus on regional patterns.