Second languages (L2s) are often learned through spoken and written input, and L2 orthographic forms (spellings) can lead to non-native-like pronunciation. The present study investigated whether orthography can lead experienced learners of English[subscript L2] to make a phonological contrast in their speech production that does not exist in English. Double consonants represent geminate (long) consonants in Italian but not in English. In Experiment 1, native English speakers and English[subscript L2] speakers (Italians) were asked to read aloud English words spelled with a single or double target consonant letter, and consonant duration was compared. The English[subscript L2] speakers produced the same consonant as shorter when it was spelled with a single letter, and longer when spelled with a double letter. Spelling did not affect consonant duration in native English speakers. In Experiment 2, effects of orthographic input were investigated by comparing 2 groups of English[subscript L2] speakers (Italians) performing a delayed word repetition task with or without orthographic input; the same orthographic effects were found in both groups. These results provide arguably the first evidence that L2 orthographic forms can lead experienced L2 speakers to make a contrast in their L2 production that does not exist in the language. The effect arises because L2 speakers are affected by the interaction between the L2 orthographic form (number of letters), and their native orthography-phonology mappings, whereby double consonant letters represent geminate consonants. These results have important implications for future studies investigating the effects of orthography on native phonology and for L2 phonological development models.