Offering such a reward may work especially well for employers who dish out thousands of dollars a year more in health insurance payouts to smokers than they spend on non-smokers, the researchers said.

And it may pay to tailor the incentive. They found that a select group of people who agreed to put down a $150 “bet” that they could kick the habit were very motivated to quit. After a year, more than half of them were still not smoking, the researchers report in the New England Journal of Medicine.

“People don’t want to part with their money,” said Dr. Scott Halpern of the University of Pennsylvania Perelman School of Medicine.