Context: Rural hospitals face multiple financial burdens. Due to federal law, emergency departments (ED) provide a gateway for uninsured and self-pay patients to gain access to treatment. It is unknown how much uncompensated care in rural hospitals is due to ED visits. Purpose: To develop a national estimate of uncompensated care from patients utilizing the ED in rural hospitals. Methods: Clinical data from the National Hospital Ambulatory Medical Care Survey-ED (NHAMCS-ED) from 1999 and 2000 were linked to billing data from South Carolina. National estimates of utilization and charges were calculated, with rurality and self-pay status being the variables of focus. Findings: Applying South Carolina billing data to national clinical data yields a national estimate for 1999-2000 of nearly $441 billion in charges being generated through emergency departments, with self-pay patients representing 9.0% of total charges. Rural self-pay patients accounted for an estimated $3.5 billion in charges in 1999 and $5.3 billion in 2000. These charges may represent a total financial burden of more than $4 billion to rural hospitals. Conclusions: Efforts should be made to reduce the uncompensated care burden on rural hospitals to ensure their viability. These efforts may include Medicaid/SCHIP expansions, FQHCs or RHCs, Critical Access Hospital Designation, or other indigent care programs that would reduce the need for self-pay patients to utilize EDs.