The audiologically deaf members of the American Deaf community display bilingual competence in American Sign Language (ASL) and English, although their language acquisition trajectories often involve delayed exposure to one or both languages. There is a great deal of variation in terms of production among these signers, ranging from very ASL-typical to productions that seem to display heavy English influence. The latter, mixed productions, coined “Contact Signing” by Lucas & Valli (1992), could be representative of a type of codeswitching, referred to as ‘code-blending’ in sign language-spoken language contexts (e.g. Baker & Van den Bogaerde 2008), in which bilinguals invoke knowledge of their two grammars in concert, or these productions could be more like a mixed language, in which a third grammar, distinct from both ASL and English, constrains them. We argue, based on the analysis of our corpus of naturalistic data collected in an all-deaf sociolinguistic environment, that Contact Signing provides evidence for code-blending, given the distribution of English vs. ASL-based language properties in the production data from the participants in our study.