80% of the time, usually it is not said at evening Mass if people seem tired, or if Priest knows Mass will take long and it is not special occasion (for example he has long homily prepared, etc…)
It’s said at all the Masses at my parish. I used to go to a parish where it was never said. If a visiting priest started saying the Confiteor, he’d get cut off by the choir singing the Kyrie because they didn’t expect him to say it.
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