Introduction: Progression of cardiac arrhythmia or heart failure often leads to treatment with a cardiovascular implantable electronic device (CIED) such as a pacemaker or pacemaker combined with an implantable cardioverter-defibrillator (ICD). Although small, hospital-based studies suggest that CIED implantation differs by sociodemographic factors, few community-based, cohort studies have prospectively evaluated it by sex, race, age, or health insurance status. Methods: We therefore examined incident CIED implantation in the Atherosclerosis Risk in Communities study (ARIC) among 15,527 eligible participants from four U.S. communities (mean age 54.2 years; 55% female; 27% Black; 90% insured) who self-identified as either Black or white and had a resting, standard twelve-lead electrocardiogram (ECG), but no ECG evidence of a pacemaker or ICD at baseline. We identified incident CIED implantation, defined as the initial device placement per participant, using International Classification of Disease (ICD)-9, ICD-10, and Current Procedural Terminology (CPT) codes during follow-up, right-censored at the time of CIED implantation, death, or end of cohort surveillance (December 31, 2020), whichever came first. We computed follow-up times and person-time denominators, then estimated the corresponding incident implantation rates overall, by sociodemographic factors, and device type. Results: Over a mean [standard deviation] follow-up of 24.0 [9.0] years, we identified 1,068 incident CIED (75% pacemaker; 25% ICD) implantations. Incident CIED implantation rates were higher among male, white, older, and insured participants (38, 30, 38, and 29 per 10,000 person-years) than among female, Black, younger, and uninsured participants (21, 23, 20, and 21 per 10,000 person-years). Relative to their counterparts, CIED incidence rates were lower among female, Black, younger, and uninsured participants: incidence rate ratio (95% confidence interval) = 0.55 (0.49-0.62), 0.77 (0.66-0.89), 0.53 (0.47-0.60), and 0.72 (0.56-0.92), respectively. When analyzed separately, patterns of incident implantation were similar for both pacemakers and ICDs. Conclusion: The sociodemographic patterning of incident CIED implantation is manifest and consistent across device type in this U.S. community-based cohort. Although the clinical, behavioral, and sociocultural reasons for the relative infrequency of implantation among female, Black, younger, and uninsured participants remain unclear, ongoing analyses are examining these differences.