Purpose. Evaluate the perceived effectiveness of key antismoking messages among highly disadvantaged smokers and assess the impact of nicotine dependence and cessation cognitions on message processing. Design. The experimental crossover trial, undertaken between March and December 2012, randomly exposed participants to two of three antismoking advertisements delivered via touchscreen computer. Setting. Welfare recipients were recruited from a community service organization in New South Wales, Australia. Subjects. Subjects were 354 smokers (79% response rate). Participants resided in government rental housing (52%), earned less than AUD$400/wk (72%), and received their primary income from government welfare (95%). Intervention. Three 30-second antismoking television advertisements representing common campaign themes: why to quit (graphic imagery), why to quit (personal testimonial), or how to quit. Measures. An 11-item scale assessed perceived effectiveness and message acceptance. An eight-item cessation cognitions index assessed motivations and readiness to quit, and the heaviness of smoking index was used to classify nicotine dependence. Analysis. Descriptive statistics, generalized linear mixed models, and multiple linear regression analyses are reported. Results. Why-to-quit advertisements were perceived as significantly more effective than the how-to-quit advertisement (all p < .0001). Smokers with positive cessation cognitions were more likely to accept antismoking messages (p = .0003) and perceive them as effective (p < .0001). Nicotine dependence level did not influence message acceptance (p = .7322) or effectiveness (p = .8872). Conclusion. Highly emotive advertisements providing good reasons to quit may be the most effective in promoting the antismoking message among groups with high smoking rates.