Introduction: Chronic spontaneous urticaria (CSU) is characterized by persistent or recurrent pruritic lesions that last more than 6 weeks. Patients with CSU may experience sleep disturbances, particularly due to itching. Biological rhythms (chronotypes) are categorized as morningness, intermediate, and eveningness types. This study evaluates the relationship between sleep quality, chronotype, and disease severity in CSU patients. Methods: The study included 53 CSU patients and 50 healthy controls. A sociodemographic data form was completed, and the disease severity was determined utilizing the Urticaria Activity Score over 7 days (UAS7). The Hospital Anxiety and Depression Scale (HADS), Insomnia Severity Index (ISI), and Pittsburgh Sleep Quality Index (PSQI) scales as well as the Morningness–Eveningness Scale (MEQ) were applied to the participants. Results: The CSU group had a significantly higher body mass index (BMI) than that of the healthy control group. In terms of sleep and chronotype scales, compared to the control group, the CSU group had higher ISI scores as well as subscale scores on the PSQI subscales, with the exception of habitual sleep efficiency and total PSQI scores. There was no difference between MEQ scores. In the correlation analysis, the UAS7 and PSQI total scores were found to be correlated, whereas in the logistic regression analysis the estimated relative risk of BMI and PSQI total score for CSU was found to be 1.13 and 1.45, respectively. Conclusions: When dealing with CSU patients, it is necessary to conduct a sleep quality assessment as part of a holistic evaluation.