Chronic obstructive pulmonary disease (COPD) and asthma impact on work productivity, but their population-based burden and clinical predictors are understudied. In this observational, real-life study, work absence of 14,383 asthma and/or COPD patients present in the MAJORICA cohort (Spain) was compared with the general population. Using multivariable regression, we studied the association of work absence with demographic and clinical characteristics. Patients with asthma and/or COPD had more work absence than the general population (15.2% vs 8.9%, p < 0.0001). Patients with asthma had more often periods of work absence compared to patients with COPD (16.0% vs 12.8%, p < 0.0001). The number of days absent were, however, less in asthma than in COPD (median: 15 days [IQR: 5–51] vs 39 days [IQR: 13–134], p < 0.001). Patients with asthma–COPD overlap were in between (14.5% with absence; median: 27 days [IQR: 10–82]). Comorbid anxiety, allergic rhinitis, and sleep apnoea were independently associated with more work absence.