Physical and behavioral characteristics of individual animals can be used as indicators of their welfare status. The objective of this pilot study was to evaluate the effect of circulation fans on indicators of broiler welfare in commercial houses during colder months in the eastern United States. This study was conducted on two flocks of 36,000 straight-run broilers raised in four commercial houses on one farm site, totaling 288,000 birds. Two houses had 16 circulation fans (Fans), and two did not (control, No Fans). At weeks 3 and 6 of age, litter moisture was measured, bird behavior was video recorded, and physical assessments of broiler welfare were conducted. Independent of treatment, mobility and active behaviors decreased as birds aged (