<b><i>Introduction:</i></b> During the first phase of the coronavirus (COVID-19) pandemic lockdowns in South Africa (SA), both alcohol and tobacco were considered non-essential goods and their sales were initially prohibited and further restricted to certain days and timeframes. This study investigates self-reported changes in alcohol consumption and tobacco smoking behaviour in the general population during the COVID-19 pandemic lockdowns in SA. <b><i>Methods:</i></b> A cross-sectional national survey was conducted in October 2021 (before the Omicron wave 4 and while SA was in low-level lockdown) among 3,402 nationally representative respondents (weighted to 39,640,674) aged 18 years and older. Alcohol consumption and tobacco use were assessed from the beginning of the lockdown towards the end of March 2020 until October 2021 using the WHO-AUDIT and the US Centre for Disease Control (CDC) Global Adult Tobacco Survey questionnaires, respectively. <b><i>Results:</i></b> Among those that drank alcohol (33.2%), 31.4% were classified as having a drinking problem that could be hazardous or harmful and 18.9% had severe alcohol use disorder during the COVID-19 lockdowns. Twenty-two per cent (22.0%) of those that reported alcohol consumption reported that the COVID-19 pandemic lockdowns changed their alcohol consumption habits, with 38.1% reporting a decreased intake or quitting altogether. Among the one in five respondents (19.2%) who had ever smoked, most reported smoking at the time of the survey (82.6%) with many classified as light smokers (87.8%; ≤10 cigarettes/day). Almost a third (27.2%) of those smoking reported that the COVID-19 pandemic lockdowns had changed their use of tobacco products or vaping, with 60.0% reporting a reduction/quitting tobacco use. Given that sales were restricted this indicates that people could still get hold of tobacco products. Heavy smoking was associated with older age (<i>p</i> = 0.02), those classified as wealthy (<i>p</i> < 0.001), those who started or increased tobacco smoking during the pandemic lockdowns (<i>p</i> = 0.01) and residential provinces (<i>p</i> = 0.04). <b><i>Conclusion:</i></b> Given restrictions on the sale of alcohol and tobacco in SA between 27 March and August 17, 2020, during the pandemic, respondents reported an overall decline in alcohol consumption and tobacco use which might suggest that the regulatory restrictive strategies on sales had some effect but may be inadequate, especially during times where individuals are likely to experience high-stress levels. These changes in alcohol consumption and tobacco use were different from what was reported in several European countries, possibly due to differences in the restrictions imposed in SA when compared to these European countries.