Purpose: Many women are being offered rapid genetic testing (RGT) for cancer predisposition genes, at the time of breast cancer diagnosis prior to surgery. The goal of this study was to determine if psychosocial functioning was affected in women receiving RGT for BRCA1 and BRCA2 at the time of breast cancer diagnosis.Methods: Participants were women with invasive breast cancer diagnosed between 2013 and 2018, at four centres in Toronto, Canada. Eligible women were referred into the study by their surgeon at the time of diagnosis. Participants received pre-test genetic counselling and were offered RGT for BRCA1 and BRCA2. Standardized questionnaires (Impact of Event Scale and Hospital Anxiety and Depression Scale) were completed before genetic counselling, and follow-up questionnaires at one-week and one-year post-genetic test result disclosure (higher scores indicate higher symptoms).Results: 1007 women had RGT; 60 women (6.0%) were found to have a BRCA1 or BRCA2 mutation, 80 women (7.9%) had a VUS, and 867 (86.1%) had a negative test result. At one-week post-testing, there were no differences in distress (p = 0.32), anxiety (p = 0.14), or depression (p = 0.42) between women with a BRCA1/2 mutation and those with a negative result. At one year, there were no differences in distress (p = 0.75) or anxiety (p = 0.13) between women with a BRCA1 or BRCA/2 mutation and those with a negative result. However, women with a BRCA1 or BRCA2 mutation had significantly lower depression scores compared to women with a negative result (p = 0.03).Conclusion: For women who have RGT for BRCA1 and BRCA2 at the time of breast cancer diagnosis, identifying a BRCA1 or BRCA2 mutation does not impair psychosocial functioning in the short or long term.