Objectives: To examine electronic cigarette use, reasons for use and perceptions of harm among university students.

Design: Cross-sectional study.

Setting: University students across New Zealand.

Methods: We analysed data from a 2018 cross-sectional survey of university students, weighted to account for undersampling and oversampling by gender and university size. χ 2 tests were used to compare e-cigarette use, reasons for use and perceptions of harm by age, gender, ethnicity and cigarette smoking.

Participants: The sample comprised 1476 students: 62.3% aged 18-20 years, 37.7% aged 21-24 years; 38.6% male, 61.4% female; 7.9% Maori and 92.1% non-Maori.

Results: 40.5% of respondents (95% CI 37.9 to 43.1) reported ever, 6.1% (4.9-7.4) current and 1.7% (1.1-2.5) daily use. Regardless of frequency, 11.5% of vapers had vaped daily for ≥1 month, 70.2% of whom used nicotine-containing devices; 80.8% reported not vaping in indoor and 73.8% in outdoor smoke-free spaces. Among ever vapers, curiosity (67.4%), enjoyment (14.4%) and quitting (2.4%) were common reasons for vaping. 76.1% (73.4-78.7) of respondents believed e-cigarettes were less harmful than cigarettes. More males than females reported vaping (ever, current, daily and daily for ≥1 month), nicotine use and belief that e-cigarettes were less harmful than cigarettes. More participants aged 18-20 years reported not vaping in outdoor smoke-free spaces, vaping out of curiosity and belief that e-cigarettes were less harmful than cigarettes, while more participants aged 21-24 years vaped daily for ≥1 month and for enjoyment. More Maori than non-Maori ever vaped. More cigarette smokers than non-smokers vaped (ever, current, daily and daily for ≥1 month), used nicotine and vaped to quit, while more non-smokers did not vape in smoke-free spaces and vaped out of curiosity.

Conclusions: Our results suggest high prevalence of e-cigarette ever and current use, particularly among males and smokers. Many vaped out of curiosity and perceived e-cigarettes as less harmful than cigarettes.