The Nasal Cycle is a periodic shift in extent of nasal airflow between the left and right nostrils. The change in dominant nostril may be linked to transitions in autonomic arousal, potentially indicating a shift between sympathetic and parasympathetic tone. Given the strong link between autonomic tone and the sensation of pain, we hypothesized that pain may be reflected in the nasal cycle. We tested for this by simultaneously measuring nasal airflow in each nostril before, during, and after pain in 11 healthy participants (M/F=7/4, mean age=29±6). To cause pain we used cold-pressor test (CPT), where participants immerse their hand in freezing water (2°C) for as long as they can, for up to 3 minutes. Pain can be estimated by both the time the participant can endure, and their self-reported subjective ratings of pain. The nasal cycle was estimated by two standard parameters: Laterality Index (LI), namely the flow ratio between the nostrils (FlowR-FlowL/FlowR+FlowL), and inter-nostril correlation (NC), namely the correlation between the flows of the two nostrils. These were entered into an rmANOVA with a condition of experimental phase (before, during pain, after). We observed a significant main effect for LI (F(2,20)=5.045, p=0.017), reflecting a shift from right to left-nostril dominance during pain (mean LI Before:0.26±0.3, During Pain:0.205±0.294, After:0.199±0.301; before vs. after: t(10)=2.82, Cohen’s d=0.85, p=0.018; before vs. pain: t(10)=2.3, Cohen’s d=0.7 p=0.044). Moreover, across participants, increased subjective pain intensity was associated with increased correlation between nostrils during pain (Spearman’s r=0.639, p=0.034). These remarkably strong effects that emerged in only 11 participants imply a genuine link between the nasal cycle and experience of pain, with clear clinical implications. Further work will determine whether this serves as merely a reflection of pain experience, or in turn, a causal determinant in sensation of pain.