Background: Oncology medication cost is often absent from therapy decision process until issues arise with payer denial resulting in potential patient financial toxicity. To incorporate cost, Best Practice Alert (BPA) and Cost Transparency Information (CTI) for high cost oncology medication (HCOM) were implemented into prescribing platform as care coordination tools. Methods: Ten HCOM were identified in gastrointestinal (GI) and breast oncology groups for which BPA and CTI were developed. Over a 6 month period, HCOM prescriptions triggered BPAs to alert providers and to place automated referrals to social work (SW). CTI – with drug costs and comparable treatment plan(s) – were posted in prescribing platform. Descriptive analyses examined differences in total payment to hospital and patients out-of-pocket payments (OPP) between treatment plans. Pre- and post-intervention surveys evaluated oncologists’ perception and behavior toward treatment cost. Results: The analysis included 162 patients and 1406 medication claims. In the GI group, BPAs effectively identified treatments incurring higher mean total payment (diff = 46733, p < 0.001) and higher mean OPP (diff = 115, p < 0.001). For the breast group, the impact was mixed. BPAs identified treatments with higher total payment at the 90% quantile (p < 0.001) and higher mean total payment (diff = 72612, p < 0.001), but there was no statistically significant difference in OPP between treatments. Pre-intervention survey (n = 26, 50% response rate) indicated 46% of oncologists rarely discuss medication cost with patients and 35% rarely refer patients to SW. Only 4% of oncologists strongly agreed that they could easily acquire cost information. Post-intervention survey highlighted that CTI improved oncologists’ awareness of medication costs, but BPA exerted no substantial influence on provider behaviors. Conclusions: BPA intervention effectively highlighted treatment cost and accurately identified patients at risk for financial toxicity. The lack of statistically significant difference in oncologists’ behavior and perception may be due to a small sample size. Comments from providers suggest that BPA combined with OPP would be more useful in reducing financial toxicity.