be on the level

To be honest, trustworthy, and genuine. My daughter's fiancé is a very respectable fellow, and his actions are always on the level. Don't worry about Jason—he's on the level. I need to you to be on the level with me: do I have any chance at this promotion?

on the level, to be

Honest, straightforward, and sincere. An American colloquialism originating in the late nineteenth century, this term may have come from Freemasonry, in which the carpenter’s level symbolizes integrity. Ngaio Marsh used it in a 1936 novel (Death in Ecstasy), “He’s on the level all right.”