Wiktionary
own up
vb. (context idiomatic English) to acknowledge, confess, or admit guilt or reponsibility. Often used with ''to''.
Usage examples of "own up".
The soldiers across the street were leaning out of their windows and hollering to where, Frank could now see, they had a barricade of their own up.
And yet you, Ruth Carew, own up to giving two Christmas-tree parties within a week, and, as I happen to know, your home, which used to be shrouded in death-like gloom, is a-flame 'with scarlet and green from top to toe.
I'm perfectly willing to own up that I'm glad I consented to keep the child and that I'm getting fond of her, but don't you rub it in, Matthew Cuthbert.