In response to COVID-19, the South African government banned the sale of tobacco products for 20 weeks. Before the ban, the illicit cigarette market was well-entrenched and smoking cessation services were not widely available. Several surveys conducted to ascertain cigarette smokers’ responses to the ban reported substantial differences in the proportion of smokers who quit. This study provides a broadly nationally representative ex-post investigation into cigarette smokers’ quitting behavior related to the sales ban. We used data from wave three of NIDS-CRAM (the National Income Dynamics Study-Coronavirus Rapid Mobile Survey) conducted in November– December 2020. We first investigated the proportion of people who quit and who continued smoking during and after the sales ban. We subsequently linked the NIDS-CRAM survey to the fifth wave of NIDS (2017) to identify a subset of established smokers, and considered whether their quitting behavior differed from that of all smokers who smoked at the start of the sales ban. The cross-sectional analysis showed that 7.8% of cigarette smokers quit during the sales ban, but that 55% of these quitters relapsed after it was lifted. Of the pre-ban smokers, 3.5% indicated that they did not smoke both during and after the sales ban, and 3.7% quit after the ban was lifted. The longitudinal analysis showed that 7% of people who were smoking in 2017, quit smoking cigarettes during the tobacco sales ban, but that >70% of quitters relapsed after it was lifted. Only 2% of pre-ban established smokers indicated that they did not smoke during or after the ban. The sales ban did not have the intended objective of encouraging large-scale smoking cessation. This reflects policy failures to provide smokers with appropriate cessation support and to effectively control the illicit market both prior to and during the sales ban.