Summary: Background: Sugar‐sweetened beverage (SSB) consumption remains high among US children. Warning labels on SSBs hold promise for reducing consumption, but their impact may differ by SSB category. Objectives: This study examined the effects of pictorial warnings on parents' beverage purchases and perceptions across SSB categories. Methods: Parents of children ages 2–12 (n = 326) visited a convenience store laboratory in North Carolina. Participants were randomly assigned to see SSBs carrying either pictorial warning labels or control labels. Parents purchased a beverage for their child and completed a survey. Results: Responses from parents in the control arm suggest underlying perceptions of flavoured milk (2.8 on scale ranging from 1 to 5), flavoured water (2.6), and fruit‐flavoured drinks (2.5) as the most healthful SSB categories. Compared to the control, pictorial warnings led to the largest reductions in purchases of fruit drinks (−61%), soda (−36%) and flavoured milk (−32%). Warnings also lowered the perceived healthfulness of flavoured water (d = −0.34), flavoured milk (d = −0.28), sports drinks (d = −0.25), and a reduction in intentions to give one's child sports drinks (d = −0.30), flavoured water (d = −0.24) and sweet tea (d = −0.22, all p < 0.05). Conclusions: Warning labels may have heterogeneous effects across SSB categories. Future research should assess the psychological mechanisms underlying these heterogeneous effects. [ABSTRACT FROM AUTHOR]