Using the New Mexico Spanish-English Bilingual Corpus, the present paper examines the variable position of the 1sg Spanish pronoun yo—pre- versus post-verbal—to consider the effect that code-switching may have on structural change. In an analysis of close to 700 tokens of yo, a rate of 16% post-positioning is found, which is within the range of post-position in non-contact varieties and thus contraindicative of the convergence hypothesis, in accordance with which the almost exclusive use of preverbal subject pronouns in English would predict lower rates of post-verbal yo in a converged contact variety. Moreover, by testing factors hypothesized to account for choice of post-posing yo using multivariate analysis, it is shown that bilinguals display similar constraints on yo post-positioning in New Mexican Spanish as monolingual speakers of Spanish, providing stronger support for an anti-convergence account. Results are discussed in terms of bilingual parallel activation, syntactic priming, and construction grammar.