wouldn't bet on it
I wouldn't bet on (something)
I think it is very unlikely that something will happen or be the case. A: "John said he'd be here by 8." B: "Yeah, I wouldn't bet on it. John has never been on time for anything in his life." Politicians talk about reform all the time, but I wouldn't bet on any legislation come out of Washington anytime soon.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
(I) wouldn't bet on it.and (I) wouldn't count on it.
Fig. I do not believe that something will happen. (Also with that or some specific happening. See examples.) John: I'll be a vice president in a year or two. Mary: I wouldn't bet on that. John: I'll pick up a turkey on the day before Thanksgiving. Mary: Did you order one ahead of time? John: No. Mary: Then I wouldn't count on it.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.