Purpose: The majority of diverticulitis presentations are uncomplicated and not expected to recur, however there is a proportion of patients who require multiple admissions for diverticulitis. Data specific to the Australian population on the risk factors and outcomes of patients with recurrent diverticulitis is lacking. Methodology: This was a retrospective population-based cohort study of all hospitalisations for colonic diverticulitis. All records of patients 18 years and over and admitted to NSW public or private hospitals between 2005-2020 were retrieved from the Admitted Patient Data Collection (APDC) database. This study aims to review the risk factors and outcomes in readmissions for diverticulitis. Results: 22% of patients required one or more readmissions for diverticulitis over 16 years. Risk factors for readmission include female, age <50 years old, complicated diverticulitis, smoking and born in Australia. Mortality was highest in the index admission (0.97%) and decreased with increasing number of admissions (p<0.001). The need for ICU admission did not change with subsequent admissions for diverticulitis (p=0.38). In patients with an initial episode of uncomplicated diverticulitis, 3.3% developed complicated diverticulitis in a subsequent episode. However, in patients with an initial episode of complicated diverticulitis, 12.1% developed complicated diverticulitis in a subsequent episode. Conclusion: Majority of patients do not have recurrent diverticulitis after one episode. Subsequent readmissions had a greater proportion of complicated diverticulitis, but mortality decreased with increasing admissions.