When listening to spoken language, bilinguals access words in both of their languages at the same time; this co-activation is often driven by phonological input mapping to candidates in multiple languages during online comprehension. Here, we examined whether cross-linguistic activation could occur covertly when the input does not overtly cue words in the non-target language. When asked in English to click an image of a duck, English-Spanish bilinguals looked more to an image of a shovel than to unrelated distractors, because the Spanish translations of the words duck and shovel (pato and pala, respectively) overlap phonologically in the non-target language. Our results suggest that bilinguals access their unused language, even in the absence of phonologically overlapping input. We conclude that, during bilingual speech comprehension, words presented in a single language activate translation equivalents, with further spreading activation to unheard phonological competitors. These findings support highly interactive theories of language processing.