When is the last time to say Selichos?


Initially, Selichos is to be recited early in the morning (In a written reply to Rabbi SZ Gurary OBM, the Rebbe decried the practice of those who “recite selichos soon after the latest time for reciting Shema.”).

After the fact, it can be recited before Mincha.


שו”ת יחו”ד ח”א סי’ מו.