Purpose <p>Time-restricted eating (TRE) helps regulate rest-activity rhythms, blood glucose, and other diurnally regulated energetics processes, which may have implications for persistent fatigue. In a randomized controlled trial, we tested the effects of TRE vs. control on fatigue in cancer survivorship.</p> Methods <p>Adult cancer survivors were recruited who were 2&#xa0;months to 2&#xa0;years post-treatment and reported moderate to severe fatigue. Participants were randomized 1:1, TRE:control, and all received individualized nutrition counseling. The TRE group self-selected a 10-h eating window for 12&#xa0;weeks. At baseline, week 6, and week 12, participants were asked to log eating instances, complete the Functional Assessment of Chronic Illness Therapy-Fatigue questionnaire (FACIT-F, higher score = less fatigue), and wear an actigraph and continuous glucose monitor.</p> Results <p>Thirty participants completed baseline assessments and were randomized (77% female, 53% Black/African American, 43% White, 7% Hispanic; 54.1 ± 14.7&#xa0;years old; 87% with blood cancer); 25 completed 12-week assessments. TRE led to a meaningful reduction in fatigue at week 12 controlling for baseline levels (change in FACIT-F fatigue subscale = 0.0 ± 5.4 for control, 4.1 ± 5.7 for TRE, <i>p</i> = 0.11, effect size (ES) = 0.70; clinically meaningful threshold = 3.0 points). Glucose parameters (e.g., average interstitial glucose, average fasting glucose) tended to be lower, and rest-activity rhythms tended to indicate more regularity for those in the TRE vs. control group at weeks 6 and 12, though differences were not statistically significant (<i>p</i> &gt; 0.19).</p> Conclusions <p>A 12-week, nutritionist-led TRE program led to less fatigue than control. Continued study of TRE patterns are warranted to optimize this eating pattern and address persistent cancer-related fatigue.</p> Trial registration <p>ClinicalTrials.gov Identifier: NCT05256888.</p>