IntroductionThe underlying factors that contribute to early radiotherapy (RT) termination are understudied, especially in the era of hypofractionated treatment regimens. In this retrospective investigation, we examined the characteristics and causes of premature RT terminations in senior adults (>70 years old) with oral cavity (OC) and laryngeal carcinomas.MethodsHundred and eighty‐eight patients treated with RT ± systemic therapy for OC and laryngeal cancer from 2017 to 2022 were identified. Premature termination was defined as completion of less than 95% of the prescribed RT. Logistic regression analysis was performed to examine factors predictive of premature termination, and survival was determined using the Kaplan–Meier method.ResultsTwenty patients (10.6%) experienced premature RT terminations. On regression analysis, ECOG score at initiation of RT was the only covariate studied to be independently associated with premature termination (OR 2.00, 95%CI: [1.21, 3.30], p = 0.007). Three‐year overall survival (49.1% vs. 77.3%) was significantly reduced in the termination cohort (p < 0.0001).ConclusionsThis analysis demonstrated over 1 in 10 patients had premature RT termination, which prognosticated inferior survival outcomes. Poor performance status may highlight patients at risk for premature termination and thus identify good candidates for hypofractionated protocols.