Aim To assess the effect of aesthetic crown lengthening (ACL) and lip repositioning surgery (LRS) on perception of smile attractiveness. Materials and methods Preoperative and 6‐month postoperative smile photographs of ACL‐ or LRS‐treated patients were evaluated by 100 raters (five gender‐balanced groups of ten per procedure) of diverse background (dental students, general dentists, periodontists and laypersons with and without any aesthetic concerns about their own smile). Smile attractiveness was rated by visual analogue scale (VAS). Multivariate mixed‐effect models were applied to determine the effect of procedure, rater (age, gender and group) and case (gingival display and GD) on smile attractiveness rating. Results Average preoperative and postoperative VAS scores for ACL patients were 3.8 ± 2.0 and 6.2 ± 1.9, respectively. Corresponding LRS patient values were 4.8 ± 2.0 and 6.4 ± 1.9. Treatment, baseline GD and rater age were significant determinants (p < .001) of smile attractiveness for both procedures. Rater gender was not significant. Rater group was significant (p < .032) only for ACL. Procedure (p < .001), baseline VAS (p < .001), change in GD (p ≤ .002) and rater age (p ≤ .017) were significant determinants of smile attractiveness change from preoperative to postoperative. Conclusions ACL and LRS are two periodontal plastic surgery procedures that deliver significant smile attractiveness improvements, in the eyes of both laypersons and dental professionals.