Rice bran (RB), a by-product of the rice milling process, is known to be a rich source of bioactive phytochemicals. This study aimed to evaluate the influence of RB stabilization treatments, usually applied to inhibit rancidification, on its phenolic composition and antioxidant activity. Findings: Total phenolic content (TPC) and antioxidant assays were performed on RB that was exposed to extrusion, drum-drying, microwave, and oven stabilization treatments. Chemical profiling was conducted using ultra-high performance liquid chromatography (uHPLC) coupled to an online ABTS system, and liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). Extrusion and drum-dried stabilization significantly increased TPC when compared to non-stabilized RB (NS-RB). All stabilization treatments increased antioxidant capacity and radical scavenging activity. uHPLC/online ABTS and LC-QTOF-MS identified all treatments to increase the concentration of free phenolic compounds and antioxidant activity compared to NS-RB. More specifically, drum-dried RB significantly altered RB phenolic composition when compared to all other treatments. Conclusions: All stabilization treatments significantly altered TPC and antioxidant activity of RB. Drum-dried RB treatment was most effective in improving free phenolic composition and antioxidant activity. Significance and novelty: This study demonstrated that drum-dried stabilization treatment may be a crucial technique that can be applied to RB to ensure essential phenolic compounds with antioxidant activity remain intact, thereby adding value to the functional and nutritional quality of RB.