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To understand the communicative functions of any vocalization it is important to first classify, describe, and measure the elements of that vocalization. Mexican (Poecile sclateri) and boreal (P. hudsonica) chickadees both produce a name-sake chick-a-dee call. Here, the note types present in samples of Mexican and boreal chick-a-dee calls are identified and described. Frequency and temporal measures of each note type are analyzed and show that frequency measures may be useful for note-type and individual discrimination. Call syntax is also analyzed and shows that both Mexican and boreal chickadees produce the notes within their chick-a-dee calls in a fixed order with the potential for any note type to be repeated or omitted within the sequence. This work provides a foundation for future studies aimed at understanding the communicative significance of this call within these species, as well as for comparative work on the chick-a-dee call among all chickadee species.