The aim of this study was to evaluate the clinical performance of S(3) Bond (Kuraray Corp., Japan) and G-Bond (GC Corp., Japan) all-in-one bonding agents, over 3 years in non-carious cervical lesions (NCCLs). Ethics Committee approval was obtained, and 60 restorations were placed in 11 patients aged 45-84 years (mean 60.5 years), using either Clearfil ST resin composite (Kuraray) and S(3) Bond or Gradia resin composite (GC) and G-Bond alternately, without phosphoric acid etch on the uncut enamel margins. Patients were recalled at 6 months, 1 year, 2 years and 3 years, and photographs were taken for assessment of colour match and marginal discoloration. One patient was not available at 3 years, resulting in 54 restorations being available for evaluation. One restoration of S(3)/Clearfil ST was lost at 2 years, giving retention rates of 97% for S(3) and 100% for G-Bond. At 3 years, six restorations for S(3)/Clearfil ST showed slight marginal discoloration and one restoration pronounced marginal staining. For G-Bond/Gradia at 3 years, 11 restorations exhibited slight marginal staining and one restoration pronounced marginal staining. Most restorations were bonded to sclerotic dentin. Statistical analysis of marginal staining showed no significant difference between the two restoration groups. The degree of marginal staining was almost identical for both materials and tended to be in larger restorations. Both S(3) and G-Bond all-in-one bonding systems appear to be good adhesives for the restoration of NCCL for the length of the current study. Restoration of NCCLs with the newer all-in-one adhesives appears to be a viable alternative technique to more complicated adhesive materials.