Background: Atrial fibrillation (AF) is a major cause of stroke. Therefore, all patients with ischemic stroke or transient ischemic attack (TIA) should be examined with 12-lead electrocardiogram (ECG) and continuous monitoring to detect AF. Current guidelines recommend at least 24 h continuous ECG monitoring, which is primarily based on studies investigating patients with ischemic stroke. The aim of our study was to investigate the diagnostic yield of 12-lead ECG and Holter monitoring in patients with TIA. Methods: We retrospectively investigated all patients diagnosed with TIA at Odense University Hospital, Denmark, from January 1, 2014 to December 31, 2014. TIA was a clinical diagnosis according to the WHO definition. Patients received admission ECG and 72-hour Holter monitoring after discharge. Results: 171 patients without known AF were diagnosed with TIA. Four (2.3%) were diagnosed with AF on admission ECG. Another 2 (1.2%) were diagnosed with AF on Holter monitoring. In total, 6 patients (3.5%) were diagnosed with AF. Patients with AF were significantly older (mean age 79.4 [95% CI 65.1-93.6] years) than patients without AF (mean age 67.6 [95% CI 65.6-69.5] years) but otherwise showed no difference in baseline characteristics. Conclusion: In this retrospective study, patients with TIA had a low incidence of AF detected with ECG and 72-hour Holter monitoring. Prospective studies are needed to confirm these findings.