Women with locally advanced breast cancer (LABC) who are breast conservation (BCT) candidates after neoadjuvant chemotherapy have the best long-term outcome and low local-regional recurrence (LRR) rates. However, young women are thought to have a higher risk of LRR based on historical data. This study sought to evaluate LRR rates in young women who undergo BCT after neoadjuvant chemotherapy. We identified 122 women aged 45 years or younger with American Joint Committee on Cancer (AJCC) Stage II to III breast cancer, excluding T4d, treated with neoadjuvant chemotherapy from 1991 to 2007 from a prospective, Institutional Review Board-approved, single-institution database. Data were analyzed using Fisher eExact test, Wilcoxon tests, and the Kaplan-Meier method. Median follow-up was 6.4 years. Fifty-four (44%) patients had BCT and 68 (56%) mastectomy. Forty-six per cent were estrogen receptor-positivity and 28 per cent overexpressed Her2. Mean pretreatment T size was 5.6 cm in the BCT group and 6.7 cm in the mastectomy group (P = 0.04). LRR rates were no different after BCT compared with mastectomy (13 vs 18%, P = 0.6). Higher posttreatment N stage (P < 0.001) and AJCC stage (P = 0.008) were associated with LRR but not pretreatment staging. Disease-free survival was better for patients achieving BCT, with 5-year disease-free survival rates of 82 per cent (95% CI, 69 to 90%) compared with 58 per cent (95% CI, 45 to 69%) for mastectomy (P = 0.03). Young women with LABC who undergo BCT after neoadjuvant chemotherapy appear to have similar LRR rates compared with those with mastectomy. This suggests that neoadjuvant chemotherapy may identify young women for whom BCT may have an acceptable risk of LRR.