Advance care planning (ACP) benefits emergency department (ED) patients with advanced illness. Although Medicare implemented physician reimbursement for ACP discussions in 2016, early studies found limited uptake. We conducted a pilot study to assess ACP documentation and billing to inform the development of ED-based interventions to increase ACP. We conducted a retrospective chart review to quantify the proportion of ED patients with advanced illness with Physician Orders for Life-Sustaining Treatment (POLST) or coding of ACP discussion in the medical record. We surveyed a subset of patients via phone to evaluate ACP participation. Of 186 patients included in the chart review, 68 (37%) had a POLST and none had ACP discussions billed. Of 50 patients surveyed, 18 (36%) recalled prior ACP discussions. Given the low uptake of ACP discussions in ED patients with advanced illness, the ED may be an underused setting for interventions to increase ACP discussions and documentation. [ABSTRACT FROM AUTHOR]