Background: Various ways to improve asthma control have been studied, with only a modest effect. Purpose: To evaluate the effect of asthma specialist visit on asthma control among adult asthma patients. Patients and methods: This matched cohort study included patients ages 21–50 with asthma and at least 1 visit to an asthma specialist. Patients were compared to adult asthma patients treated only by primary care physicians. The study outcomes, included use of asthma medication, healthcare visits, and mortality. All outcomes were compared one year before and after specialist visit. Results: 4166 pairs were included in the study. In the study group, a statistically significant decrease in the average number of relievers (1.5 ± 3.2 vs. 1.17 ± 2.9, p < 0.001) and systemic steroids purchased (0.53 ± 1.2 vs. 0.4 ± 1.2, p < 0.001), with an increase in average number of inhaled steroid purchased (1.6 ± 2.5 vs. 2.3 ± 33, p < 0.001) was seen over time. A significant decrease in the average number of PCP visits (9.5 ± 7.2 vs. 8.9 ± 7.3, p < 0.001), emergency department (ED) visits (0.46 ± 1 vs. 0.4 ± 0.9, p = 0.05) and all-cause hospitalization (0.03 ± 0.22 vs. 0.01 ± 1.9, p < 0.001) was seen in the study group but not in controls. Generalized linear modeling demonstrated an overall significant effect of specialist intervention for all parameters (p < 0.01), except ED visits (p = 0.06). During follow-up, eight (0.2%) study group patients vs. 19 (0.5%) controls died (p = 0.03). Conclusion: We found that asthma specialist intervention significantly improved asthma outcomes in adults. Referring adult asthma patients to an asthma specialist should be a goal of asthma management plans. Trial registration: Not relevant.