Background: Sutureless bioprothesis aortic valves simplify surgery for aortic valve replacement (AVR) but some anatomical features of the recipients aortic annulus might preclude anchoring and lead to paravalvular leak. Sub-commissural annuloplasty (SCAP) has been sporadically proposed to secure implantation under these circumstances. This study evaluated whether SCAP affects early postoperative outcomes after sutureless Perceval-S implantation. Methods: We included all patients who underwent AVR (isolated or combined with coronary bypass) with the Perceval-S valve from March 2016 to August 2019. SCAP was performed each time the surgeon deemed it useful to improve anchoring, including after primary implantation failure. Results: One hundred and three patients were included. Mean age was 73.9±7.2 years and 36(35%) were women. SCAP was performed in 34(33%) patients, significantly more frequently in patients with large aortic annulus or bicuspid aortic valve. Perceval-S implantation was successful in 100(97%) patients and SCAP allowed successful redeployment of the same Perceval S valve in 4(28%) of first implantation failures. Thirty-day mortality was 2% (n=2), of which one was related to the procedure. There was no significant difference in the incidence of postoperative conduction disorders between patients with and without SCAP (respectively, 3[9%] vs 7[10%], p=1.0). More than trivial paravalvular leak was noted in 1(1%) patient without SCAP. Postoperative peak and mean pressure gradients were lower in patients with than in those without SCAP (respectively, 19.0±7.9 mmHg vs 23.1±7.0 mmHg, p=0.001; and 10.4±4.1 versus 12.6±3.7 mmHg, p=0.001). Conclusions: SCAP is a safe, simple and reproducible technique that might facilitate Perceval-S aortic valve implantation.