Postdischarge costs associated with primary arthroplasty surgeries have received limited attention in the literature. Our objective was to identify the costs incurred after discharge in primary arthroplasty and to estimate annual postdischarge expenditures in the United States. A cohort of 136 patients who underwent primary arthroplasty was studied. Comprehensive rehabilitation unit (CRU) and home care (HC) costs were obtained. The National Hospital Discharge Survey 2003 data were used to model the national discharge cost estimates. Local patient-oriented outcome was also compared in the patients discharged to CRU vs HC. Total costs were significantly lower in patients discharged directly to home vs those sent to the CRU and who subsequently received HC ($2405 vs $13435, P < .001); both patient groups experienced similar quality of life improvements. An estimated $3.2 billion is spent annually on postsurgical rehabilitation after arthroplasty. Postdischarge costs are significantly higher for patients going to a CRU vs those discharged home; yet, both groups had comparable short-term outcomes.