Final kissing-balloon inflation is often recommended for percutaneous coronary intervention (PCI) of bifurcation lesions. However, randomized trials focusing on kissing inflation have not confirmed its beneficial impact. We compared outcomes of kissing inflation for PCI of bifurcation lesions, explicitly stratifying results according to stenting strategy. Patients undergoing bifurcation PCI were retrospectively enrolled. Subjects receiving final kissing inflation were compared with those not undergoing kissing inflation, after stratification for a single-stent technique. The primary end point was the long-term rate of major adverse cardiac events (MACE, i.e., death, myocardial infarction, or target lesion revascularization (TLR)). A total of 4314 patients were included: 1176 (27.3 %) treated with a single stent and kissing inflation, 1637 (37.9 %) with a single stent but no kissing, 1072 (24.8 %) with two stents and kissing, and 429 (9.9 %) with two stents but no kissing. At unadjusted analyses kissing was associated with fewer short-term MACE and deaths in the two-stent group, and with fewer long-term MACE, cardiac deaths, and side-branch TLR in the two-stent group (all P < 0.05). Conversely, kissing appeared detrimental after single stenting. However, after multivariable analyses, kissing no longer significantly affected the risk of adverse events, with the exception of the risk of side-branch TLR, which was lower in those receiving two stents and final kissing inflation (hazard ratio = 0.52, 95 % confidence interval 0.30–0.90, P = 0.020). Kissing inflation can be avoided in bifurcation lesions uneventfully treated with single-stent PCI. However, final kissing-balloon inflation appears beneficial in reducing the risk of side-branch repeat revascularization after using a two-stent strategy.