Twenty-one thousand eight hundred sixty-four arthroplasties (THA = 11,105; TKA = 10,759) were performed between 2010 and 2014 at our institution, in which 60 patients (THA = 37, TKA = 23) were readmitted during this 5-year period. The most common reasons for readmission were fracture (N = 14), infection (N = 14), and dislocation (N = 9). Thirty-day readmission for THA was associated with increased procedure time (P = .05), length of stay (LOS) shorter than 2 days (P = .04), discharge to a skilled nursing facility (P = .05), and anticoagulation use other than aspirin (P = .02). Thirty-day readmission for TKA was associated with increased tourniquet time (P = .02), LOS <3 days (P < .01), and preoperative depression (P = .02). In the combined THA/TKA model, a diagnosis of depression increased 30-day readmission (odds ratio 3.5 [1.4-8.5]; P < .01).