Patients with chronic obstructive pulmonary disease (COPD) are routinely prescribed one or more inhaled medications. Adherence to inhaler medications and correct inhaler device technique are crucial to successful COPD management. The goals of this study were to estimate adherence and inhaler technique in a cohort of COPD patients. This was an observational study conducted on a sample of 150 COPD patients. Medication adherence was assessed using the Medication Adherence Report Scale (MARS). Inhaler technique was assessed using standardized checklists. Clinical data were collected using a proforma. Of the 150 patients (mean age 70.3 years, 52% male), 58% reported suboptimal adherence (MARS ≤ 24). High adherence to therapy (MARS = 25) was associated with older age (p = 0.001), but not any of the other studied variables. Medication non-adherence was not associated with COPD exacerbations. Errors (≥ 1) in inhaler technique were common across all of the types of inhaler devices reportedly used by patients, with the highest proportion of errors among Turbuhaler users (83%) and the least proportion of errors among Handihaler users (50%). No clinical variables were associated with errors in inhaler technique. Suboptimal adherence and errors in inhaler technique are common among COPD patients. No clinical variables to assist in the prediction of medication non-adherence and poor inhaler technique were identifiable. Consequently, regular assessment of medication adherence and inhaler technique should be incorporated into routine clinical practice to facilitate improved health outcomes among patients with COPD.