Objectives:To evaluate patients’ sleep quality in a former hospital with two-and four-bedded rooms compared to a new hospital that incorporated evidence-based design features, including exclusively single-patient rooms (SPRs).Background:Hospitalized patients often report poor sleep quality due to both patient-related factors and hospital environmental factors. It is unclear if staying in an SPR in a hospital designed as a healing environment is associated with better sleep quality.Methods:In a before-after study, sleep quality, duration, and efficiency over 72 hr were measured with a sleep diary, GENEActiv accelerometer, and the Richards–Campbell Sleep Questionnaire (RCSQ) with scores ranging from 0 to 100, with higher scores reflecting better sleep. Participants were either staying alone in the former hospital with two-and four-bedded rooms (Group 1), sharing a room with one to three fellow patients (Group 2), or staying alone in a newly designed hospital with 100% SPRs (Group 3).Results:We included 17 patients in Group 1, 32 patients in Group 2, and 56 patients in Group 3. Univariable linear mixed model analysis, controlling for night number, revealed that the RCSQ total score was lowest in Group 2 compared to the other two groups. In the multivariable analysis, the RCSQ score was also the lowest in Group 2, with a significant effect from covariate “use of night medication.”Conclusion:Self-reported sleep quality of hospitalized patients in a hospital with 100% SPRs designed as a healing environment was slightly better than that of patients staying in multioccupancy rooms with fellow patients.