Self-pay patients are an understudied yet important and financially vulnerable population of emergency department (ED) users. As ED facility fees may be a key cost driver in patient ED bills, we leveraged newly available hospital pricing data to describe ED facility fees for self-pay patients (cash prices) and how they vary according to hospital and regional characteristics in a sample of 1,621 hospitals across the United States. The median cash price for ED facility fees ranged from $160.78 for a level 1 visit to $1,097.43 for a level 5 visit. Hospital for-profit status and a bed count of 251 or more beds were associated with higher cash prices for ED facility fees across all visit levels. Meanwhile, location in a county with a poverty rate of 16 percent or more was correlated with lower facility fee cash prices for ED visit levels 2 and up. We hope that these findings can inform targeted policy efforts to better ensure affordable ED care for vulnerable patients.