Within the Competition Model, cue validity and cue cost can serve to make predictions about real-time sentence processing in a cross-linguistic perspective. Previous research with monolingual children and adults in French (Kail 2004) and Swedish (Kail et al. 2012) proposed that cue cost is determined by contextual and structural information, word order and morphology. On the basis of online grammaticality judgments, we investigated whether these cue cost constraints are equally efficient and follow the same hierarchy in simultaneous French/Swedish bilinguals and in their monolingual counterparts. Although bilinguals were slower and less accurate, the weight of each cue cost component was similar for both groups. Bilinguals’ longer detection times are linked to specific interactions between cue cost components not observed in monolinguals. This result is compatible with the cognitive cost implied by the need to inhibit the non-relevant language during bilingual processing.