<p>In asthma, suboptimal disease control is common due to limited knowledge about self-management, undertreatment and infrequent follow-up visits. Most patients are treated in primary care where asthma/COPD clinics (ACC) are recommended in Sweden, but evidence of the effects is limited. The aim was to compare certified ACCs with clinics providing regular care in terms of adherence to asthma management guidelines, and the associations with asthma symptom control, healthcare consumption, and mortality in adults with asthma. In this cohort study, we extracted data from the Swedish National Airway Register, on 84230 adults with asthma, cared for at certified ACCs (n = 17 primary care centres) and regular care clinics (n = 650 primary care centres) in Sweden. Data were linked to other national registers in order to obtain data about pharmaceuticals, healthcare consumption, and mortality. The index date was the years 2015–2017, and the study ended in 2022. A binary logistic regression was used to assess morbidity and mortality associations at the study’s end. A higher proportion of patients at certified ACCs received interventions such as patient education, written asthma action plan, smoking cessation, Asthma Control Test, spirometry, and inhaled corticosteroids than patients at regular care clinics. Certified ACCs were associated with a lower probability of uncontrolled asthma (OR 0.76, 95% CI 0.67–0.87), need of specialist/emergency care (OR 0.69, 95% CI 0.51–0.92) and death (OR 0.69, 95% CI 0.55–0.86). In conclusion, adherence to asthma management guidelines was higher in certified ACCs which were associated with a more well-controlled asthma, less secondary healthcare visits and lower all-cause mortality, but not with frequent exacerbations. Our findings highlight the importance of ACCs in providing evidence-based care in accordance with asthma management guidelines.</p>