Tobacco smoking is widely recognised as one of the leading threats to population health. Around 21% of the Thai population currently smoke. It was estimated that 51,000 deaths and 755,000 disability-adjusted life years (DALYs) lost are due to tobacco use. Results from published meta-analyses suggest that mobile health (mHealth) interventions for smoking cessation are beneficial; however, there is variability among the mHealth literature, suggesting that these interventions are often complex in nature. An improved ability to define and recognise behaviour change techniques (BCTs) would help researchers enhance their knowledge regarding effective behaviour change interventions. A lack of evidence for the effectiveness and cost-effectiveness of mHealth interventions in developing countries limits its usage in Thailand. The aim of this research is to improve smoking cessation rates among Thai smokers by using an mHealth behaviour change intervention, assessing the value for money of text messaging interventions, and developing recommendations for the economic evaluation of public health interventions from this case study.