Purpose: This study was conducted to further evaluate and improve antithrombotic stewardship efforts and decrease perceived overutilization of FXai levels in the emergency department at our institution. Summary: A retrospective chart review was completed for patients seen in the emergency department of a 545-bed tertiary care referral center, between July 1, 2022, to June 30, 2023. The primary outcome was determining the appropriateness of ordering a factor Xa inhibitor (FXai) level based on a previously defined list of potential appropriate indications for testing. Once this primary review was completed, the investigator reviewed the clinical utility of the list and if the levels meaningfully contributed to overall patient care. When this secondary review was completed, a revised list of appropriate indications for FXai testing in the emergency department was developed and utilized to create an algorithm for appropriate FXai utilization. Patients had a mean age of 70 years old and 57% of patients were male. Most patients were anticoagulated for atrial fibrillation, 61%. For the primary outcome, 69 (57%) FXai levels were considered appropriate based on the initial appropriateness criteria. After the list Conclusion: This study led to the development of an appropriate use algorithm for ordering FXai levels in the emergency department. Prospective validation of the algorithm is needed.