One reason for performing the ECG routinely on asymptomatic persons is to assist the physician in determining the need for hospitalization should acute cardiac symptoms later develop. To establish how often baseline ECGs are actually useful in this situation, we reviewed the records of 236 patients presenting to two emergency departments with the complaint of chest pain. Of these patients, 195 (82.7%) had clinical or ECG findings sufficiently diagnostic that the baseline ECG could not have affected the decision to hospitalize or discharge. For 11 patients (4.7%) with equivocal clinical and ECG findings, a baseline ECG (if it was available) might have been useful in avoiding an unnecessary hospitalization. There was no patient for whom a baseline ECG would have aided in avoiding an inappropriate discharge. The routine ECG has little value as a baseline for emergency comparison when patients later experience acute cardiac symptoms. Routine ECGs as baselines for future comparison should be reconsidered.