<p>Long COVID (LC) is a complex multisymptom condition with no known disease-modifying treatments. This wait-list-controlled open-label trial tested whether a remotely delivered structured weight management program could improve respective LC symptoms in people living with overweight. Adults with LC (symptoms &gt;12 weeks) and body mass index &gt;27 kg m⁻² (&gt;25 kg m⁻² for South Asians) were randomized (<i>n</i> = 234, 1:1) to control (<i>n</i> = 116, usual care) or the remotely delivered structured weight management (<i>n</i> = 118, total diet replacement (850 kcal per day) for 12 weeks, followed by food reintroduction and weight loss maintenance support) via minimization and randomization (80:20) to balance dominant LC symptom, sex, age, ethnicity and postcode-based index of multiple deprivation between groups. The control group received the intervention after 6 months. Participants selected the dominant LC symptom they would most like to improve (fatigue, breathlessness, pain, anxiety/depression or other) as the prespecified respective primary outcome. Individual symptoms were assessed using validated questionnaires and a visual analog scale for those without prespecified scales. At 6 months, the primary outcome improved in the intervention group (change −1.16 (s.d. 1.42), <i>n</i> = 97 analyzed) compared with the control group (change −0.83 (s.d. 1.14), <i>n</i> = 117 analyzed) with a treatment effect of −0.34 (95% confidence interval −0.67 to −0.01), with no excess of serious adverse events. International Standard Randomised Controlled Trial Number Registry registration: ISRCTN<a href="https://doi.org/10.1186/ISRCTN12595520">12595520</a>.</p>