Background: The American Society of Hematology (ASH) recommends reducing inpatient thrombophilia testing but adherence to these recommendations remains suboptimal. We report the results of a quality improvement (QI) project which aimed to minimize unnecessary testing. Methods: We performed retrospective review of records of patients with a new diagnosis of venous thromboembolism (VTE) across 3 hospitals in Central PA from September 2021 to December 2021 to see how many patients underwent thrombophilia workup. Our QI project consisted of education for physicians based on ASH recommendations with lectures, biweekly emails, and educational posters. We then performed a second retrospective review of patients admitted under the same conditions between June 1, 2022, and August 31, 2022, to reevaluate thrombophilia testing rates. The cost of testing was extrapolated from institutional hospital cost reports. Descriptive statistics included reporting the categorical variables as number and percent. The categorical variables were compared between groups with Fisher’s exact test or the chi-square test. Results: During the first study period, 310 patients had new VTE. Provoking factors were found in 269 patients (86.7%) and 41 patients (13.2%) had unprovoked VTE. Overall, 33 out of 310 patients (10%) underwent thrombophilia workup, with a total of 175 tests performed. Thrombophilia testing rate was significantly higher in the unprovoked group (29.3% vs 7.8%, p = 0.0003). Both groups have equally received inpatient hematology consult (33.83% vs 47.50%, p = 0.0920). Only 16% of thrombophilia tests were recommended by hematology consult while the rest was ordered by the primary team. The cost of all tests ordered outside of hematology recommendation was $34,083 ($344 per person). Of the group that got tested regardless of provoking factors, there was no difference between hospital length of stay (2-12 days vs 3-12 days, p = 0.0665) or anticoagulation choice. During the second study period, 191 patients had new VTE. Provoking factors were found in 157 patients (82.1%) while 34 patients (17.9%) had unprovoked VTE. Overall, 21 out of 191 patients (10.9%) underwent thrombophilia workup, with a total of 78 tests performed. More testing was ordered in the unprovoked group (26.47% vs 7.64%, p = 0.0040). More inpatient hematology consults were performed in the unprovoked group (64.71% vs 40.76%, p = 0.0110). Of the hematology consults, 12 out of 21 patients (57%) had thrombophilia testing recommended by hematologist. The rate of thrombophilia testing ordered outside of hematology consultation has decreased from 84% to 43% after our intervention, resulting in a $16,635 savings for that quarter. Conclusions: Our experience confirmed that thrombophilia work up was costly and did not impact quality of care. Despite the relatively low frequency of inpatient workup, eliminating unnecessary testing saved our health system $16,635 in a 3-months period.