BACKGROUND AND AIMS: Comparing regulatory models for nicotine vaping products in different countries can provide insights into the most effective regulatory approach but can be confounded by cross-national differences. This study compared two neighbouring countries with very different vaping regulatory models but with similar tobacco control policies and population demographics. Australia has a highly restrictive, prescription-only vaping policy, while New Zealand adopted a regulated consumer model.

METHODS: This study compared trends in daily smoking and vaping among adults and youth from 2016 to 2023 in Australia (adults ≥14 years and ≥15 years; youth 12-17 years) and New Zealand (adults ≥15 years, youth 14-15 years), using published statistics from large nationally representative surveys.

RESULTS: Between 2016 and 2023, the decrease in adult daily smoking in New Zealand (from 14.5% to 6.8%) was larger than in Australia (from 12.2% to 8.3%) by a factor of 0.67 [95% confidence interval (CI) = 0.43, 0.93]. However, the increase in adult vaping in New Zealand (from 0.9% to 9.7%) was larger than in Australia (0.5% to 3.5%) by a factor of 0.56 (95% CI = 0.17, 1.02). The largest smoking reductions in both countries were in young adults, who also reported the highest vaping rates. There was a more rapid decline in smoking in the lower socioeconomic groups and Indigenous people in New Zealand than in Australia. Youth smoking rates declined in both countries to very low levels. Youth vaping rates in New Zealand were higher but have started to decline since regulations were introduced.

CONCLUSIONS: If the association is causal, New Zealand's less restrictive approach to vaping (compared with Australia's more restrictive approach) may have contributed to a more rapid decline in adult smoking, and reduced social inequalities and Indigenous smoking, but at the possible expense of increased youth vaping.