Background <p>Healthcare costs increase rapidly in aging societies. Research on service use is warranted in this context.</p> Aims <p>To examine predicting factors and costs associated with hospitalizations among home care clients aged ≥ 65 years.</p> Methods <p>Baseline data collection included demographic characteristics, diagnoses, morbidity (Charlson Comorbidity Index, CCI), basic and instrumental activities of daily living (BADL, IADL), Timed up and Go (TUG), Mini-Mental State Examination (MMSE) and health-related quality of life (EQ-5D-3&#xa0;L). Univariate and multivariate logistic regressions were used to identify factors predicting hospitalization and gamma regression with a log link to analyze cumulation of inpatient days during one-year follow-up. Hospitalization costs were calculated using national unit costs of healthcare.</p> Results <p>During follow-up, 176 (60%) of 293 regular home care clients were hospitalized. In univariate analyses, hospitalizations were statistically significantly associated with CCI, heart failure, peripheral vascular disease, renal failure, BADL, IADL and Eq.&#xa0;5D3L. In multivariate analysis, only higher CCI (<i>p</i> = 0.008) predicted increased odds for hospitalization. Several diseases, number of medicines, BADL, IADL and MMSE were associated with inpatient days in univariate analyses. MMSE alone remained significant (<i>p</i> = 0.039) in multivariate analysis, higher scores predicted fewer days. Total hospitalization costs were €2,370,910, with €1,267,519 attributable to primary care and €1,103,391 to secondary care. Costs in the cohort were €9,225 per person-year.</p> Discussion <p>Over half of regular home care clients required hospitalization with substantial costs during one year. Greater comorbidity burden predicted hospitalizations and cognitive impairment increased inpatient days.</p> Conclusions <p>Optimal disease management and maintenance of functioning should be prioritized in home care.</p>