Objective Though interest in expansion of the use of less-invasive therapies among operable non-small-cell lung cancer (NSCLC) patients is growing, it is not clear that post-treatment surveillance has been comparable between treatment modalities. We sought to characterize institutional surveillance patterns after NSCLC therapy with stereotactic body radiation therapy (SBRT) and lobectomy. Methods NSCLC patients treated with lobectomy or SBRT (2005 to 2016) at a single institution were identified. Natural language processing searched data fields within axial surveillance imaging reports for findings suggestive of recurrence. Duration and patterns of institutional surveillance were compared between the 2 groups. Results Three thousand forty-two patients (73.5% lobectomy, 26.5% SBRT) met inclusion criteria. Patients had a longer median duration of surveillance after lobectomy (28.0 months vs SBRT 12.3 months, P < 0.001) and were more likely to undergo histopathological evaluation of clinically suspected relapse (206/274 [75.2%] vs SBRT 54/113 [47.8%], P < 0.001). Patients with clinical suspicion of recurrence had longer durations of institutional surveillance than those who did not among both cohorts (lobectomy 44.4 months vs 25.9, P < 0.001; SBRT 27.9 vs 10.3, P < 0.001). Landmark analyses at 1 and 3 years after therapy identified associations between receipt of lobectomy and ongoing surveillance at each time point (1 year odds ratio [OR] 2.10, P < 0.001; 3 years OR 1.71, P < 0.001) among all patients and those with documented stage I disease. Conclusions We identified potential heterogeneity in institutional surveillance patterns after treatment of NSCLC with 2 therapeutic modalities. As less-invasive treatment options for operable patients expand, it will be critical to implement rigorous surveillance paradigms across all modalities.