Background – Chronic rhinosinusitis (CRS) is a common disorder, with up to an estimated 134 million Indian sufferers, and having significant impact on quality of life (QOL) and health costs. Despite the evidence favoring homeopathy in CRS being inadequate, it is highly popular. This trial attempts to study the efficacy of individualized homeopathy (IH) medicines in comparison with placebo in patients with CRS. Methods – A double-blind, randomized (1:1), placebo-controlled, preliminary trial (n = 62) was conducted at the National Institute of Homoeopathy, West Bengal, India. Primary outcome measure was the sino-nasal outcome test-20 (SNOT-20) questionnaire; secondary outcomes were the EQ-5D-5L questionnaire and EQ-5D-5L visual analog scale scores, and five numeric rating scales (0–10) assessing intensity of sneezing, rhinorrhea, post-nasal drip, facial pain/pressure, and disturbance in sense of smell, all measured at baseline and after the 2nd and 4th months of intervention. Group differences and effect sizes (Cohen’s d) were calculated on the intention-to-treat sample. Results – Groups were comparable at baseline. Attrition rate was 6.5% (IH: 1, Placebo: 3). Although improvements in both primary and secondary outcome measures were higher in the IH group than placebo, with small to medium effect sizes, the group differences were statistically non-significant (all p > 0.05, unpaired t-tests). Calcarea carbonica, Lycopodium clavatum, Sulphur, Natrum muriaticum and Pulsatilla nigricans were the most frequently prescribed medicines. No harmful or unintended effects, homeopathic aggravations or any serious adverse events were reported from either group. Conclusion – There was a small but non-significant direction of effect favoring homeopathy, which ultimately renders the trial as inconclusive. Rigorous trials and independent replications are recommended to arrive at a confirmatory conclusion. [Trial registration: CTRI/2018/03/012557; UTN: U1111–1210–7201].