The L2 acquisition of French infinitival complements (e.g., chercher à ‘seek to’ + infinitive, essayer de ‘try to’ + infinitive, vouloir Ø ‘want to’ + infinitive) involves learning that the choice of preposition (à, de, or null element) preceding the infinitive is arbitrary and must be acquired on a case-by-case basis. English (participants’ L1 in the present study) uses only the preposition to in this context. This study sought to answer the following questions: (1) What types of errors do less and more proficient Anglophone L2 learners make with infinitival complements introduced by the prepositions à, de or a null element ?; (2) Is one variant overgeneralized as a default form ? We hypothesized that (1) all learners would make incorrect preposition choices, (2a) that à would be overgeneralized by the less proficient learners due to cross-linguistic influence, (2b) while de would be overgeneralized by the more proficient learners due to input frequency. We examined 11 learners’ (six less proficient, five more proficient) production and comprehension of French infinitival complements using a cloze test and a grammaticality judgment task and found (i) errors with preposition choice; (ii) an overgeneralization of the variant de, that we propose is due to its high frequency in the input.