Introduction: Tiotropium, a once-daily long-acting anticholinergic bronchodilator, has recently been approved for use in the treatment of asthma in a number of countries, including the EU and the USA, and was incorporated into the 2015 update of the Global Initiative for Asthma treatment guidelines. Here we review safety data from published clinical trials to help inform the use of tiotropium in the treatment of patients with asthma. Areas covered: Safety data from recently published clinical trials, which compared tiotropium with placebo or an active control, were reviewed. Trials included children, adolescents, and adults across severities of symptomatic asthma, and assessed tiotropium delivered via the Respimat and HandiHaler devices. Expert opinion: Based on the reviewed scientific evidence, tiotropium is a safe and well-tolerated long-acting anticholinergic bronchodilator for use in the treatment of asthma. In the trials assessed, the safety of tiotropium was found to be comparable with that of placebo and alternative therapeutic options, including a doubling in the dose of inhaled corticosteroids and the long-acting β2-agonist salmeterol.