it will cost you

it/that will cost (one)

1. Something will cost a large amount of money, especially compared to a cheaper or simpler option. You can opt to rent a larger van instead of the sedan, but it will cost you. A: "Jane and Joe want to upgrade their tickets to first class." B: "There's still time to do it, but that'll cost them. Are they sure it's worth it?" A: "Will you promise not to tell Mom?" B: "It'll cost you."
2. Something will have a negative impact on one's performance or chance of success. A: "Uh oh, the quarterback just fumbled the ball on his own 20 yard line!" B: "Ouch, that'll cost them big time. They really can't afford to give up any more points this late in the game." You can try to fluff up your résumé a bit when you apply for the job, but it'll cost you if your interviewers find out.
See also: cost, that, will
Farlex Dictionary of Idioms.

it will ˈcost you

(spoken) used to say that something will be expensive: There is also a de luxe model available, but it’ll cost you.
See also: cost, will
Farlex Partner Idioms Dictionary
See also:
  • it/that will cost (one)
  • opt for
  • opt for (something)
  • something else, he/she/it is
  • low rent
  • low-rent
  • pad out
  • comfortable circumstances
  • opt in
  • opt in (to something)
References in periodicals archive
"Holding assets in joint name with your spouse may make your home life easier, but it will cost you flexibility," he says.