INTRODUCTION: Despite the rapid increase in electronic cigarettes (e-cigarette) use, little is known regarding its effects on maternal health. We examined the association between maternal e-cigarette use before pregnancy and hypertension (preexisting and gestational). METHODS: We obtained data from phase 8 (2016–2019) of the Pregnancy Risk Assessment Monitoring System (PRAMS; N=153,336). Postpartum mothers reported their e-cigarette and combustible cigarette use within the 3 months before pregnancy. They also reported hypertension status before pregnancy and gestational hypertension. We used multivariable logistic regression models to estimate the adjusted odds ratio (aOR) of hypertension associated with maternal e-cigarette use and cigarette use before pregnancy, controlling for sociodemographic and pregnancy confounders. RESULTS: Compared to nonusers, mothers who exclusively used cigarettes (7.0% versus 4.8%, aOR 1.33 [95% CI 1.32–1.35]) and dual users (8.4% versus 4.8%, aOR 1.98 [95% CI 1.95–2.02]) before pregnancy had an increased risk of hypertension before pregnancy, whereas exclusive e-cigarette smokers had a decreased risk of hypertension before pregnancy (4.5% versus 4.8%, aOR 0.95 [95% CI 0.92–0.98]). Exclusive cigarette users (10.1% versus 9.0%, aOR 1.03 [95% CI 1.02–1.04]), exclusive e-cigarette users (11.3% versus 9.0%, aOR 1.22 [95% CI 1.20–1.25]), and dual users (10.4% versus 9.0%; aOR 1.13 [95% CI 1.11–1.15]) in the 3 months before pregnancy had a higher risk of gestational hypertension compared to nonusers. CONCLUSION: Combustible cigarette use and dual use before pregnancy was associated with an increased risk of hypertension before pregnancy and gestational hypertension. E-cigarette use before pregnancy was associated with increased risk for gestational hypertension only.