No, you can’t get an STI from kissing. STIs, or Sexually Transmitted Infections, are passed between sexual partners through oral, vaginal, or anal sex. There are some infections that people can get through sex or through other ways. For example, HSV (herpes simplex virus) can be passed through sex or by things like kissing or sharing lip balm. If it was passed through sex, it’s considered an STI. If it was passed through something like kissing or sharing lip balm, it wouldn’t be considered an STI.