Background The landscape of tobacco and nicotine delivery products has rapidly evolved with the introduction of electronic nicotine delivery systems (ENDSs) and oral nicotine pouches (ONPs). Understanding sales trends and flavour preferences is critical for assessing these products’ public health impact and informing regulatory strategies. Objective To characterise recent trends in US sales of ENDS and ONPs from 2018 to 2023, overall and by flavour. Methods Information Resources retail sales data covering 40 states from 7 January 2018 to 16 July 2023, were used to document trends in ENDS and ONP sales from brick-and-mortar retailers, by product flavour (non-menthol, mint/menthol and tobacco/unflavoured) in 4 week periods. Results ENDS and ONP sales have shown significant growth, with notable fluctuations coinciding with public health concerns and regulatory announcements. Specifically, non-menthol flavoured ENDS initially experienced a decline in sales following regulatory actions in early 2020 but strongly rebounded thereafter. Meanwhile, ONP sales have increased steadily, dominated by mint/menthol flavours. These trends may reflect consumer flavour preferences as well as manufacturers’ strategic responses to policy changes. Sensitivity analyses using more recent sales data from 24 states confirm that these patterns persist. Conclusions Differences in ENDS and ONP sales trends by flavour type underscore the importance of ongoing, detailed monitoring of nicotine product sales and use, to clarify public health implications and guide regulation. Given the growing variety of nicotine and tobacco products available today, tobacco regulatory frameworks must consider trends across this rapidly evolving market to understand and mitigate associated public health risks.