Background: Mammography screening may cause psychosocial harm for women experiencing a false-positive screening result. Previous studies suggest long-term consequences. The aim of the present study was to assess psychosocial consequences of false-positive findings on screening mammography within a six month follow-up. Methods: A prospective matched cohort survey study using the questionnaire ‘Consequences of Screening for Breast Cancer’ (COS-BC), which was translated from Danish to Norwegian. Psychometric analyses investigated the measurement properties of the Norwegian version. Two screening clinics in Norway distributed the survey to 299 women with an abnormal mammogram and 541 women with a normal screen. Women received the questionnaire when receiving the screening result, and one and six months after screening. Results: At six months, statistically significant differences appeared in two scales: existential values and breast examination. At six-month follow-up, women with false-positive results showed no statistically significant differences from women diagnosed with breast cancer in three outcomes: sense of dejection, anxiety, and keeping my mind off things. Conclusion: Our results indicate that the psychosocial consequences from having false-positive screening mammography results diminish after six months. The results support previous research describing breast-specific outcomes. However, our results indicate that Norwegian women are less frightened than other Scandinavian mammography screening participants.