Mass media are increasingly used to deliver health messages to promote social and behaviour change, but there has been little evidence of mass media use for improving a set of child feeding practices, other than campaigns to promote breastfeeding. This study aimed to examine the factors influencing the uptake of infant and young child feeding messages promoted in TV spots that were launched and aired nationwide in Bangladesh. We conducted a mixed‐methods study, using household surveys (n = 2,000) and semistructured interviews (n = 251) with mothers of children 0–23.9 months and other household members. Factors associated with TV spot viewing and comprehension were analysed using multivariable logistic regression models, and interview transcripts were analysed by systematic coding and iterative summaries. Exposure ranged from 36% to 62% across 6 TV spots, with comprehension ranging from 33% to 96% among those who viewed the spots. Factors associated with comprehension of TV spot messages included younger maternal age and receipt of home visits by frontline health workers. Three direct narrative spots showed correct message recall and strong believability, identification, and feasibility of practicing the recommended behaviours. Two spots that used a metaphorical and indirect narrative style were not well understood by respondents. Understanding the differences in the uptake factors may help to explain variability of impacts and ways to improve the design and implementation of mass media strategies.