This study compared Spanish-English bilinguals' and English monolinguals' VOT values for /b, d, g/ in cognates and non-cognates. Twenty-six young adult participants (fourteen bilinguals and twelve monolinguals, mean age 24 years) were administered a picture-naming task, balanced for cognate and non-cognate forms. VOT values of 30 target words per participant and per language were measured. The data support cross-linguistic interaction in bilinguals' phonologies and indicate that cognates can interfere with bilinguals' phonemic distinctions. In English, bilinguals' VOTs exhibited significantly greater lead voicing than monolinguals', and, for all participants, /b/ had longer lead voicing than /d/ and /g/. Comparing bilinguals' VOTs for Spanish versus English revealed significant differences by language (English shorter), between /b/ and /g/, and between cognates and non-cognates, with shorter lead voicing in cognates than in non-cognates. More detailed results showed that in bilinguals' Spanish productions with word-initial /d/ and English productions with word-initial /b/, cognates exhibited shorter lead voicing (more English-like) than non-cognates. The conclusion is that the bilinguals' VOTs exhibited some cross-linguistic influence in relation to cognate usage, in the direction toward their dominant language, English. Further analyses also revealed a role of current daily usage in VOT performance.