The mammalian carotid body (CB) is excited by blood‐borne stimuli including hypoxia and acid hypercapnia, leading to respiratory and cardiovascular reflex responses. This chemosensory organ consists of innervated clusters of receptor type I cells, ensheathed by processes of adjacent glial‐like type II cells. ATP is a major excitatory neurotransmitter released from type I cells and type II cells express purinergic P2Y2 receptors (P2Y2Rs), the activation of which leads to the opening of ATP‐permeable, pannexin‐1 (Panx‐1) channels. While these properties support crosstalk between type I and type II cells during chemotransduction, direct evidence is lacking. To address this, we first exposed isolated rat chemoreceptor clusters to acute hypoxia, isohydric hypercapnia, or the depolarizing stimulus high K⁺, and monitored intracellular [Ca²⁺] using Fura‐2. As expected, these stimuli induced intracellular [Ca²⁺] elevations (Δ[Ca²⁺]_i) in type I cells. Interestingly, however, there was often a delayed, secondary Δ[Ca²⁺]_i in nearby type II cells that was reversibly inhibited by the P2Y2R antagonist suramin, or by the nucleoside hydrolase apyrase. By contrast, type II cell stimulation with the P2Y2R agonist uridine‐5′‐triphosphate (100 μm) often led to a delayed, secondary Δ[Ca²⁺]_i response in nearby type I cells that was reversibly inhibited by the Panx‐1 blocker carbenoxolone (5 μm). This Δ[Ca²⁺]_i response was also strongly inhibited by blockers of either the adenosine A_2A receptor (SCH 58261) or of the 5′‐ectonucleotidase (AOPCP), suggesting it was due to adenosine arising from breakdown of ATP released through Panx‐1 channels. Collectively, these data strongly suggest that purinergic signalling mechanisms mediate crosstalk between CB chemoreceptor and glial cells during chemotransduction.