Way 1 · best default
I'll be honest with you
A signal that the truth is coming. It sounds caring, not harsh.
Examples
I'll be honest with you, I don't think he's right for the job.
I'll be honest with you: I'm a bit worried about the cost.
In a conversation
A: So, what did you think of my presentation?
B: I'll be honest with you. The start was great, but it was too long.
Common mistake
Not: I'll be honest to you.
Say: I'll be honest with you.
In English you're honest "with" someone, not "to" them.