Background: Although some investigations of phonological development have found that segmental accuracy is comparable in monolingual children and their bilingual peers, there is evidence that language use affects segmental accuracy in both languages. Aims: To investigate the influence of age of first exposure to English and the amount of current input-output on phonological accuracy in English and Spanish in early bilingual Spanish-English kindergarteners. Also whether parent and teacher ratings of the children's intelligibility are correlated with phonological accuracy and the amount of experience with each language. Methods & Procedures: Data for 91 kindergarteners (mean age = 5;6 years) were selected from a larger dataset focusing on Spanish-English bilingual language development. All children were from Central Texas, spoke a Mexican Spanish dialect and were learning American English. Children completed a single-word phonological assessment with separate forms for English and Spanish. The assessment was analyzed for segmental accuracy: percentage of consonants and vowels correct and percentage of early-, middle- and late-developing (EML) sounds correct were calculated. Outcomes & Results: Children were more accurate on vowel production than consonant production and showed a decrease in accuracy from early to middle to late sounds. The amount of current input-output explained more of the variance in phonological accuracy than age of first English exposure. Although greater current input-output of a language was associated with greater accuracy in that language, English-dominant children were only significantly more accurate in English than Spanish on "late" sounds, whereas Spanish-dominant children were only significantly more accurate in Spanish than English on "early" sounds. Higher parent and teacher ratings of intelligibility in Spanish were correlated with greater consonant accuracy in Spanish, but the same did not hold for English. Higher intelligibility ratings in English were correlated with greater current English input-output, and the same held for Spanish. Conclusions & Implications: Current input-output appears to be a better predictor of phonological accuracy than age of first English exposure for early bilinguals, consistent with findings on the effect of language experience on performance in other language domains in bilingual children. Although greater current input-output in a language predicts higher accuracy in that language, this interacts with sound complexity. The results highlight the utility of the EML classification in assessing bilingual children's phonology. The relationships of intelligibility ratings with current input-output and sound accuracy can shed light on the process of referral of bilingual children for speech and language services.