If the bonus was not merely performance based but was reflected in a signed written bonus or employment agreement from the company--that is, you had a written contract guarantying the bonus--then you could sue for breach of contract if they don't pay you the amount they contracted to pay, based upon the provable performance.But if the bonus was not encapsulated in a written contract, it was subject to change at will by the company.You write that the "company did not issue a bonus plan at any point during the year, but in prior years, the prior program had been carried over." That means that there was no in-effect written bonus agreement. The carrying over of prior plans in prior years was voluntary or discretionary on the company's part: they chose to do that, but were not required to do so, and could choose to NOT do so at will.Therefore, based on what you write, you do not appear to have an enforceable guaranty of or right to a given bonus, and would not have recourse.