Objectives The purpose of the study was to investigate whether postpartum depression is associated with a risk of depression during perimenopause. Study design This is a Danish nationwide register-based cohort study of 270,613 individuals who were born in 1960–1968, who gave birth to a liveborn child recorded in the Medical Birth Register before the age of 40, and who lived in Denmark when turning 47 years old. The association between postpartum depression and depression during perimenopause was analyzed using a Cox proportional hazards model adjusted for education level, marital status, and age at first delivery. Main outcome measures Depression during perimenopause was identified by a diagnosis of depression during nine years of follow-up registered in the Danish National Patient Registry. Results A total of 7694 (2.9 %) study participants were diagnosed with depression during perimenopause. Postpartum depression was associated with 12.82 [95 % confidence interval (CI): 8.93;18.41] times higher hazard of depression during perimenopause, while depression prior to study baseline was associated with 11.91 [95 % CI: 11.14;12.73] times higher hazard compared with individuals with no history of depression. There was no difference in the association between postpartum depression and depression prior to study baseline for depression during perimenopause. Conclusion Prior depression, no matter the timing, is associated with markedly higher risk of depression during perimenopause. Thus, individuals who have experienced postpartum depression do not experience a greater risk of depression during perimenopause compared with individuals who have experienced depression unrelated to periods of hormonal changes during their fertile life.