OBJECTIVE To compare the clinical performance of a universal adhesive in class V non-carious cervical lesions (NCCLs) using two surface treatment protocols (self-etch [SfE] vs selective-enamel-etch [SelE]). METHODS Thirty-three adults, each with ≥2 NCCLs, received one resin composite restoration utilizing a SfE universal adhesive and another utilizing the adhesive and SelE with 37% phosphoric acid. Restorations were evaluated for sensitivity, retention, marginal discoloration, marginal adaptation, and clinical acceptability through 24 months using Cochran-Mantel-Haenszel tests for stratified, ordered categorical outcomes. RESULTS Sixty-six restorations (35 SfE, 31 SelE; 27 volunteers) were evaluated at 24 months. There were no significant differences between SfE and SelE for sensitivity, retention, marginal adaptation, or clinical acceptability. One SfE restoration was lost. Marginal adaptation was significantly worse at 24 months than baseline for SelE (P = 0.01), but not for SfE. Marginal discoloration was significantly worse for SfE (P = 0.02), but not for SelE. Sensitivity improved from baseline to 24 months for both groups (SelE P = 0.004, SfE P = 0.002). CONCLUSIONS Twenty-four-month data indicated significantly reduced sensitivity for both groups, worse marginal discoloration for SfE, and worse marginal adaptation for SelE. No changes in retention or clinical acceptability were observed in either group. All retained restorations were clinically acceptable at 24 months. CONCLUSIONS Both self-etch and selective enamel etch techniques with a universal adhesive produced clinically acceptable results in resin composite restorations for NCCLs over 2 years.