Key summary pointsAimTo investigate the association between multimorbidity and readmission amongst patients on Transitional Aged Care Program (TACP).FindingsHospital readmission rates increased with multimorbidity and the Charlson Comorbidity Index (CCI) is independently associated with a 30-day hospital readmission in TACP cohort.MessageIdentifying vulnerability to readmission, such as multimorbidity may allow future exploration of targeted interventions to optimise transitional care and individualise patient care to improve functional independence and prevent premature Residential Aged Care Facilities (RACF) admissions in older people.