Background: Although well established, population based screening and family risk assessment for breast cancer have come under increasing scrutiny. The concept of over diagnosis is increasingly cited in cancer publications. This study assessed the impact of failure to screen or risk assess patients attending with a new diagnosis of breast cancer. Methods: A retrospective review was undertaken of 200 consecutive patients diagnosed with breast cancer between January 2010 and September 2012 at Letterkenny Hospital. Appropriate screening was defined as biennial in those aged 50 - 66 and in those 40 - 49 with moderate/high family history risk (NICE criteria or IBIS criteria). Patient demographics, screening history, diagnosis date and stage (TNM) were documented. Patients with previous breast cancer were not included (n = 17). Results: 200 consecutive patients, whose mean age was 61 (range 28 - 99), were studied. 112/200 (56%) met no criteria for screening or family history assessment, and 88/200 (44%) met criteria for either screening (in 56) or family history assessment (in 32). 61/88 (69.3%) meeting criteria did not have a mammogram or risk assessment. The stage of breast cancer was significantly earlier in those screened appropriately, with early stage cancer in n = 111/139 (79.9 %) and late in n = 28/139 (20.1%), compared with 38/61 (62.3%) and 23/61 (37.7%) in those failing to be screened appropriately (p = 0.01 χ² df1). Conclusion: Failure to engage in breast screening and risk assessment resulted in more advanced stage at diagnosis.