Objective To provide a foundation to justify the presence of a full-time clinical pharmacist in the ambulatory cancer center in addition to an existing centralized pharmacist through cost avoidance calculation and patient and staff satisfaction surveys. Methods The prospective, pilot study took place in an ambulatory cancer center over four weeks in 2014. Cost avoidance values were assigned to interventions performed by a pharmacy resident, who was present in the ambulatory cancer center during clinic hours, along with a centralized oncology pharmacist routinely working with the cancer center. Anonymous patient and staff satisfaction surveys based on a 5-point Likert scale were distributed to assess the perceived benefit of a pharmacist located in the ambulatory cancer center. Results Data collection took place over approximately one month. After evaluation of 962 interventions from both pharmacists, the estimated cost avoidance was US$282,741 per pharmacist per year, yielding a net benefit of US$138,441. The most common interventions made by the resident included chemotherapy regimen review (n = 290, 69%) and patient counseling (n = 102, 24%), while the majority of the centralized pharmacist's interventions was chemotherapy regimen review (n = 525, 97%). Results from the anonymous patient and staff surveys revealed an overall positive perception of the pharmacy resident while in the ambulatory cancer center. Conclusion A full-time clinical pharmacist in an ambulatory cancer center is both financially beneficial and positively perceived by patients and staff.