Background Survival rates for breast cancer (BC) are increasing, leading to growing interest in treatment-related late-effects. The aim of the present study was to explore late effects using Patient-Reported Outcome Measures in postmenopausal BC survivors in standard follow-up care. The results were compared to age- and gender-matched data from the general Danish population. Material and methods Postmenopausal BC survivors in routine follow-up care between April 2016 and February 2018 at the Department of Oncology, Aarhus University Hospital, Denmark were asked to complete the EORTC QLQ-C30 and BR23 questionnaires together with three items on neuropathy, myalgia, and arthralgia from the PRO-CTCAE. Patients were at different time intervals from primary treatment, enabling a cross-sectional study of reported late effects at different time points after primary treatment. The time intervals used in the analysis were year ≤1, 1–2, 2–3, 3–4, 4–5 and 5+. The QLQ-C30 results were compared with reference data from the general Danish female population. Between-group differences are presented as effect sizes (ESs) (Cohen’s d). Results A total of 1089 BC survivors participated. Compared with the reference group, BC survivors reported better global health status 2–3 and 4–5 years after surgery (d = 0.26) and physical functioning 2–3 years after (0.21). Poorer outcomes in BC survivors compared with the reference group were found for cognitive functioning (0–4 and 5+ years), fatigue (0–2 years), insomnia (1–3 years), emotional functioning (3–4 years), and social functioning (≤1 year after surgery) with ESs ranging from 0.20 to 0.41. For the remaining outcomes, no ESs exceeded 0.20. Conclusion Only small to medium ESs were found for better global health and physical functioning and poorer outcomes for cognitive functioning, fatigue, insomnia, emotional functioning, and social functioning in postmenopausal BC survivors, who otherwise reported similar overall health-related quality of life compared with the general Danish female population.