This paper evaluates the use of intonational cues during word segmentation in French. Specifically, we aim to examine how the characteristics of the fundamental frequency (F0) that can be observed at the beginning of words influence their processing. Native speakers of French were presented with phonemically identical sequences, such as /selami/ ( c’est l’amie/la mie “it’s the friend/the crumb”). To test which properties of the F0 affect the perceived segmentation, we manipulated the F0 slope and/or the mean value of the first vowel /a/ in consonant-initial items (e.g., la mie). To assess differences in off-line vs online processing, we used a two-alternative, forced-choice task in Experiment 1 and a lexical decision task in Experiment 2. A previous study showed that vowel-initial segmentation was enhanced when the F0 mean value increased. However, the present study shows that modifying the F0 slope while keeping the F0 mean value constant also influences speech segmentation in both off-line and online tasks. This suggests that listeners use the F0 slope as a cue at the beginning of content words.