Background: Return to work is important financially, as a marker of functional status and for self-esteem in patients developing chronic illness. We examined return to work after first heart failure (HF) hospitalization. Methods: By individual-level linkage of nationwide Danish registries, we identified 21 455 patients of working age (18–60 years) with a first HF hospitalization in the period from 1997 to 2012. Of these patients, 11 880 (55%) were in the workforce before HF hospitalization and comprised the study population. We applied logistic regression to estimate odds ratios for associations between age, sex, length of hospital stay, level of education, income, comorbidity, and return to work. Results: One year after first HF hospitalization, 8040 (67.7%) returned to the workforce, 2981 (25.1%) did not, 805 (6.7%) died, and 54 (0.5%) emigrated. Predictors of return to work included younger age (18–30 versus 51–60 years; odds ratio [OR], 3.12; 95% confidence interval [CI], 2.42–4.03), male sex (OR, 1.22; 95% CI, 1.12–1.34), and level of education (long-higher versus basic school; OR, 2.06; 95% CI, 1.63–2.60). Conversely, hospital stay >7 days (OR, 0.56; 95% CI, 0.51–0.62) and comorbidity including history of stroke (OR, 0.55; 95% CI, 0.45–0.69), chronic kidney disease (OR, 0.46; 95% CI, 0.36–0.59), chronic obstructive pulmonary disease (OR, 0.62; 95% CI, 0.52–0.75), diabetes mellitus (OR 0.76; 95% CI, 0.68–0.85), and cancer (OR, 0.49; 95% CI, 0.40–0.61) were all significantly associated with lower chance of return to work. Conclusions: Patients in the workforce before HF hospitalization had low mortality but high risk of detachment from the workforce 1 year later. Young age, male sex, and a higher level of education were predictors of return to work.