We evaluated the prevalence of major and minor electrocardiographic (ECG) abnormalities based on blood pressure (BP) control and hypertension (HTN) treatment resistance. We analyzed data from the Reasons for Geographic and Racial Differences in Stroke study of 20,932 participants who were divided into presence of major (n = 3782), only minor (n = 8944), or no (n = 8206) ECG abnormalities. The cohort was stratified into normotension (n = 3373), pre-HTN (n = 4142), controlled HTN (n = 8619), uncontrolled HTN (n = 3544), controlled apparent treatment-resistant HTN (aTRH, n = 400), and uncontrolled aTRH (n = 854) groups, and the prevalence ratios (PRs) of major and minor ECG abnormalities were assessed separately for each BP group. The full multivariable adjustment included demographics, risk factors, and HTN duration. Compared with normotension, the PRs of major ECG abnormalities for pre-HTN, controlled HTN, uncontrolled HTN, controlled aTRH, and uncontrolled aTRH groups were 1.01 (0.90-1.14), 1.30 (1.16-1.45), 1.37 (1.23-1.54), 1.42 (1.22-1.64), and 1.44 (1.26-1.65), respectively (P < .001), whereas the PRs of minor ECG abnormalities among each of the above BP groups were similar. Detection of major ECG abnormalities among hypertensive persons with poor control and treatment resistance may help improve their cardiovascular risk stratification and early intervention.