Background Coronary CT angiography with noninvasive fractional flow reserve (FFR) predicts lesion-specific ischemia when compared with invasive FFR. The longer term prognostic value of CT-derived FFR (FFR ) is unknown. Purpose To determine the prognostic value of FFR when compared with coronary CT angiography and describe the relationship of the numeric value of FFR with outcomes. Materials and Methods This prospective subanalysis of the NXT study (Clinicaltrials.gov: NCT01757678) evaluated participants suspected of having stable coronary artery disease who were referred for invasive angiography and who underwent FFR, coronary CT angiography, and FFR . The incidence of the composite primary end point of death, myocardial infarction, and any revascularization and the composite secondary end point of major adverse cardiac events (MACE: cardiac death, myocardial infarction, unplanned revascularization) were compared for an FFR of 0.8 or less versus stenosis of 50% or greater on coronary CT angiograms, with treating physicians blinded to the FFR result. Results Long-term outcomes were obtained in 206 individuals (age, 64 years ± 9.5), including 64% men. At median follow-up of 4.7 years, there were no cardiac deaths or myocardial infarctions in participants with normal FFR . The incidence of the primary end point was more frequent in participants with positive FFR compared with clinically significant stenosis at coronary CT angiography (73.4% 80 of 109 vs 48.7% 91 of 187, respectively; < .001), with the majority of outcomes being planned revascularization. Corresponding hazard ratios (HRs) were 9.2 (95% confidence interval CI: 5.1, 17; < .001) for FFR and 5.9 (95% CI: 1.5, 24; = .01) for coronary CT angiography. FFR was a superior predictor compared with coronary CT angiography for primary end point (C-index FFR , 0.76 vs coronary CT angiography, 0.54; < .001) and MACE (FFR , 0.71 vs coronary CT angiography, 0.52; = .001). Frequency of MACE was higher in participants with positive FFR compared with coronary CT angiography (15.6% 17 of 109 vs 10.2% 19 of 187, respectively; = .02), driven by unplanned revascularization. MACE HR was 5.5 (95% CI: 1.6, 19; = .006) for FFR and 2.0 95% CI: 0.3, 14; = .46) for coronary CT angiography. Each 0.05-unit FFR reduction was independently associated with greater incidence of primary end point (HR, 1.7; 95% CI: 1.4, 1.9; < .001) and MACE (HR, 1.4; 95% CI: 1.1, 1.8; < .001). Conclusion In stable patients referred for invasive angiography, a CT-derived fractional flow reserve (FFR ) value of 0.8 or less was a predictor of long-term outcomes driven by planned and unplanned revascularization and was superior to clinically significant stenosis on coronary CT angiograms. Additionally, the numeric value of FFR was an independent predictor of outcomes. © RSNA, 2019 See also the editorial by Dennie and Rubens in this issue.