The effect of windfall gains on the sunk-cost effect

Prior research has extensively documented the sunk-cost effect - an irrational attention to irrecoverable past costs while making pending investment or consumption decisions, In a series of experiments, we show that the sunk-cost effect weakens and sometimes disappears when consumers receive a windfall (unexpected) income at the time of making a decision. This unbudgeted income allows consumers to write off their past losses, thereby eliminating the press-are to consume in order to satisfactorily close the account. We further show that the similarity between the nature of the windfall income and the past sunk-cost moderates this relationship. More generally, we argue that mental accounts can be flexible and consumers may have discretion in moving money between different mental accounts.