It depends on the circumstances. The company could not tell you that the increase was 83% if they also represent that the increase in cost was all due to the insurer raising the premium, when in fact the insurer raised it only 37%  and the company is pocketing the extra 46%. On the other hand, since companies do NOT need to provide health insurance, and if they do, they can have their employees pay more or less of the premium, the employer could legitimately decide that employees need to pay a larger share. The key is, they cannot lie or deceive the employees as to where the money is going, but if they want to charge employees more and subsidize  them less, they can do that.