Background Exposure to tobacco and alcohol on-screen promotes use and despite regulations and policies to limit impact, these behaviours remain common. We report a longitudinal analysis of tobacco, e-cigarette and alcohol content in three popular UK television soap operas, to examine changing social norms between 2002 and 2022.

Methods We used one-minute interval coding to measure content in programmes in two one-week periods in three years (2002, 2012 and 2022). Change in the probability of actual and implied use of tobacco, e-cigarette and alcohol over time was examined using logistic regression.

Results We coded 2505 intervals from 78 episodes. Tobacco content occurred in 22% of episodes and significantly decreased from 2002 to 2022 (OR 0.15 95% CI 0.06–0.40). Tobacco use changed over time with decreasing use indoors and increasing use outdoors. No e-cigarette use was identified. Alcohol content was found in 88% of episodes and while it also significantly decreased over time (OR 0.78 95% CI 0.61–0.99) it featured in 20% of broadcast minutes in 2022. Alcohol use in homes increased over time.

Conclusion While tobacco imagery is increasingly rare in these three UK soap operas, alcohol content has remained common. Tightening the UK Ofcom regulations would help to reduce young people’s exposure to these harmful behaviours and their potential influence on social norms now and in the future.