BACKGROUND AND OBJECTIVES: Asthma self-management strategies remain core components of evidence-based asthma care. Despite this, only 14% of Australian adults with asthma have written action plans. We aimed to evaluate whether targeted SMS reminders to attend an asthma review could improve asthma action plan and spirometry completions for general practice patients who do not have current asthma action plans. METHOD: A randomised controlled trial comparing targeted SMS reminders with usual care was performed from May to September, 2016, in a metropolitan general practice in South East Queensland. RESULTS: By the three-month follow-up, 35 of 79 patients allocated to intervention had completed action plans in comparison to five of 59 patients allocated to usual care (P < 0.0001). There were more recorded instances of spirometry per patient performed during the follow-up period for intervention (37/79), compared with usual care (8/59; P <0.0001). DISCUSSION: SMS reminders may be a useful tool in the spectrum of care needed for optimal asthma management in general practice.