The extent of endoscopic sinus surgery (ESS) required for optimal outcomes in chronic rhinosinusitis (CRS) is undefined. We evaluated whether concordance between the extent of surgery and degree of radiographic disease influences postoperative outcomes. 247 CRS patients who underwent ESS were retrospectively assigned a concordance score reflecting the similarity between the extent of surgery and degree of radiographic disease. 0 points were assigned when sinusotomy was performed on a diseased sinus, or no sinusotomy was performed on a nondiseased sinus; plus 1 for sinusotomy on a nondiseased sinus; and -1 for a diseased sinus left unopened. The total possible score ranged from minus 10 to plus 10. Patients were divided into 5 subgroups according to variance from complete concordance. SNOT-22 scores and revision rates were compared at 6 and 24 months. All five subgroups had similar preoperative SNOT-22 scores and improved at 6 months postoperatively. At 6 months postoperatively, the most conservatively operated and most extensively operated subgroups each achieved equivalent improvements in SNOT-22 as the completely concordant subgroup. At 24 months, the most extensively operated subgroup had a 12.5-point smaller improvement in SNOT-22 scores compared to the completely concordant subgroup. Multivariate analysis showed no association between concordance score and revision rate. Symptom improvement and revision rates after ESS do not appear to correlate with the degree of concordance between extent of surgery and radiographic disease. More extensive surgery than indicated by CT confers neither greater symptomatic improvement nor long-term detriment.