Background: ER testing in breast DCIS identifies patients who benefit from endocrine manipulation. We hypothesized that ER and PR testing on both biopsy and surgical tumor specimen may increase costs without improving patient outcomes. Methods: We reviewed pathology records of patients diagnosed with DCIS on breast core biopsies that had surgery performed in two community hospitals in Michigan from 2008 to 2016. The association between retesting and categorical variables (testing site, ER/PR expression, grade) was analyzed using a chi-square test. Results: We identified 239 patients who were diagnosed with DCIS on core biopsy and underwent surgery (lumpectomy or mastectomy). Average age of diagnosis was 60.5 years. 37.1% cases had grade 3 DCIS and 15% were ER-/PR-. Only one case had ER-/PR+ DCIS. Repeat ER and PR testing was performed in 39.3% of DCIS cases. The rate of repeat testing varied between the hospitals (80/133 and 14/106 cases, p-value < 0.0001). There was no difference in grade 3 DCIS and ER-/PR- DCIS on biopsies between hospitals (17.4% vs 14.1%, p-value = 0.58; 34.8% vs 39.8%, p-value = 0.49 respectively). Repeat testing was performed in both ER and/or PR+ DCIS (38.6%) and ER-/PR- DCIS (51.3%). In regards to hormone receptor expression, there was no difference in retest patterns between two hospitals. However, pathologists in one hospital more often performed repeat testing if high grade DCIS was identified on biopsy (65.2% vs 14.6%, p-value < 0.0001). 4.1% of patients had invasive disease and 6.2% of patients with DCIS underwent bilateral mastectomy. In such cases, initial reflex ER/PR testing on DCIS core biopsy specimens was not necessary. Only one patient had discordant ER/PR results. Conclusions: Our study reports a wide variation of repeat ER/PR testing in breast DCIS in a community setting and confirms a very low discordance rate of ER/PR between biopsy and surgical excision. ER-/PR+ DCIS is a rare entity and questions the role of PR testing in DCIS. The estimated cost of repeat ER/PR testing is $441.76 per case. Avoiding reflex ER/PR testing in DCIS core biopsies and repeat retesting on the surgical specimen will decrease cost of care without compromising patient outcomes.