Background: Social disparities permeate non-small cell lung cancer (NSCLC) treatment, yet little is known about the effect of insurance status on the delivery of guideline surgical treatment for early-stage (I or II) NSCLC. Methods: We used the California Cancer Registry (1996 through 2008) to identify patients 50 to 94 years old with early-stage NSCLC. We used logistic regression models to assess whether or not insurance status (private insurance, Medicare, Medicaid, no insurance, and unknown) had an effect on whether or not a lobectomy (or bilobectomy) is performed. Results: A total of 10,854 patients met our inclusion criteria. Compared with patients with private insurance, we found that patients with Medicare (adjusted odds ratio [aOR] 0.87; 95% confidence interval [CI]: 0.79 to 0.95), Medicaid (aOR 0.45; 95% CI: 0.36 to 0.57), or no insurance (aOR 0.45; 95% CI: 0.29 to 0.70) were significantly less likely to undergo lobectomy, even after adjusting for patient factors (age, race, and gender) and tumor characteristics (histology and tumor size). Increasing age, African American race, squamous cell carcinoma, and increasing tumor size were significant independent negative predictors of whether or not a lobectomy was performed. Conclusions: Patients without private insurance were significantly less likely than patients with private insurance to undergo a lobectomy for early-stage NSCLC. The variables(s) contributing to this disparity have yet to be elucidated. © 2013 The Society of Thoracic Surgeons.