Background The tobacco industry has a long history of opposing tobacco control policy and promoting socially responsible business practices. With the rise of social media platforms, like Twitter, the tobacco industry is enabled to readily and easily communicate these messages.

Methods All tweets published by the primary corporate Twitter accounts of British American Tobacco (BAT), Imperial Brands PLC (Imperial), Philip Morris International (PMI) and Japan Tobacco International (JTI) were downloaded in May 2017 and manually coded under 30 topic categories.

Results A total of 3301 tweets across the four accounts were analysed. Overall, the most prominent categories of tweets were topics that opposed or critiqued tobacco control policies (36.3% of BAT’s tweets, 35.1% of Imperial’s tweets, 34.0% of JTI’s tweets and 9.6% of PMI’s tweets). All companies consistently tweeted to promote an image of being socially and environmentally responsible. Tweets of this nature comprised 29.1% of PMI’s tweets, 20.9% of JTI’s tweets, 18.4% of Imperial’s tweets and 18.4% of BAT’s tweets. BAT, Imperial, JTI and PMI also frequently used Twitter to advertise career opportunities, highlight employee benefits, promote positive working environments and bring attention to awards and certifications that the company had received (11.6%, 11.1%, 19.3% and 45.7% of the total tweets published by each account, respectively).

Conclusions Transnational tobacco companies are using Twitter to oppose tobacco control policy and shape their public identity by promoting corporate social responsibility initiatives in violation of WHO Framework Convention on Tobacco Control. Regulation of the tobacco industry’s global online activities is required.