Background: The standard of care for pancreatic cancer (PC) patients with resected stage I to III is adjuvant chemotherapy. The role of adjuvant treatment for sub-centimeter T1 stage is unknown. This study evaluated treatment patterns and survival outcomes in T1 stage PC using National Cancer Database (NCDB). Methods: Retrospective review of the NCDB was conducted for T1 (tumor confined to the pancreas and 2 cm across or smaller), lymph node negative, surgically resected PC and no prior therapy. Patient demographics, tumor histology, treatment modalities, and survival trends were examined between 2004 and 2013. Adjuvant treatments were analyzed. Kaplan-Meier analysis and the log-rank tests were performed to determine the unadjusted association between overall survival (OS), size and treatment. Results: A total of 964 patients met criteria for inclusion. The median age was 66 (32-90). Majority were Caucasian (N = 807, 83.7%); 53.5% were female (N = 515), and moderately differentiated (N = 447, 46.4%). Tumors of 1-2cm constituted 71.2% (N = 686); 28.8% < 1cm (N = 178). Majority had negative surgical margins (N = 887, 93.3%). Patients who received surgery alone were 48.3% (N = 466); 27.5% received adjuvant chemotherapy (N = 265), and 22.6% had adjuvant chemotherapy and radiation (N = 218). Patients with < 1cm tumors who received adjuvant therapy had a median OS that was not reached v. 85.3 mo who received surgery alone (P = 0.41). In patients with 1-2 cm tumors, the median OS for patients who received adjuvant treatment was 70.7 mo v. 30.8 mo for patients who received surgery alone (P < 0.0001). The 12-mo, 24-mo, and 60-mo survival was 93.2%, 75.6% and 53.6% respectively, v. 72.5%, 61.0%, and 31.0%, respectively, for patients who received surgery alone. These results of adjuvant therapy for tumors < 1 cm v. 1-2 cm are paralleled for patients who received adjuvant chemotherapy (P = 0.08), and any adjuvant radiation (P = 0.15). Conclusions: This is the first report of adjuvant treatment analysis for resected PC patients with sub-centimeter stage I disease. Adjuvant treatment does not appear to improve survival in sub-centimeter T1, stage I PC.