Breast Cancer Awareness Month (BCAM) increases screening attendance in the USA. However, this effect has not been investigated in Europe, where organized screening is widespread. We examined monthly attendance within the Norwegian Breast Cancer Screening Programme, 2005-15. Relative to October, the odds of attending screening in January, February, March, August, September or December were slightly decreased (ORadj 0.93-0.98, P = 0.003 for all). BCAM may marginally increase attendance in October but seasonal factors such as weather may also explain this observed variation. Furthermore, it is possible that organized screening with predetermined appointments evens out the effect BCAM has on screening attendance.