Research Findings: This study examines the frequency of reasoning talk used by 56 educators during their naturally occurring play interactions with infants in their early childhood education and care (ECEC) centers. Using Hasan's semantic framework, reasons were coded as social (based on social rules) or logical (based on rules of nature). The communicative function of reasoning talk was coded as regulatory (when the reason served to regulate infants' behavior) or non-regulatory. On average, educators' reasoning talk comprising only 4.43% of their total talk, with social reasoning used slightly more frequently than logical reasoning. Educators used significantly more social reasoning when regulating infants' behavior, whereas logical reasoning occurred more frequently during non-regulatory interactions. Educators' qualification level explained individual differences. Bachelor-qualified educators used significantly more reasoning talk than lower-qualified educators, and this finding was explained by their more frequent use of both social and logical reasoning when regulating infants' behavior. Practice or Policy: The study identifies reasoning talk as an important element of language environment quality in ECEC infant rooms, and highlights the learning potential of language used for different communicative purposes. Findings demonstrate that well-qualified educators appear well versed to capitalize on the educative potential of this type of talk.