Background. The most common chemotherapies in metastatic soft tissue sarcoma (mSTS) require intravenous (IV) administration. This often requires patients to make multiple outpatient visits per chemotherapy cycle, possibly impeding patients' daily activities and increasing caregiver burden and medical costs. This study investigated costs associated with IV cancer therapy administration in mSTS from the payer perspective of the health care system. Patients and Methods. From the Experian Healthcare database, 1,228 mSTS patients were selected. Data were analyzed on outpatient visits during 2005-2012 involving IV cancer therapy administration. Costs were estimated on a per patient per visit (PPPV) and per patient per month (PPPM) basis. Results. The mean (median) cost of IV therapy was $2,427 ($1,532) PPPV and $5,468 ($4,310) PPPM, of which approximately 60% was IV drug costs. IV administration costs averaged $399 PPPV and $900 PPPM, representing 16.5% of total visit costs. Anthracycline and alkylating-agents-based therapies had the highest PPPV and PPPM IV administration costs, respectively (mean $479 and $1,336, resp.). Patients with managed care insurance had the highest IV administration costs (mean $504 PPPV; $1,120 PPPM). Conclusions. IV administration costs constitute a considerable proportion of the total costs of receiving an IV cancer therapy to treat mSTS.