Coalition loyalty programs, loyalty cash-back programs that enable their members to accrue and redeem points at a wide-range of affiliated outlets, are emerging. In a coalition loyalty program, unlike in a single-brand loyalty program, points accrued from one outlet can be redeemed in other outlets which even may be of other brands than the very one where the points were from. However, in spite of such systematic characteristic of coalition loyalty programs, there is only little research on the effect of the program. The present study is aimed at examining the difference between the effects of a coalition and a single-brand loyalty program in terms of acquisition and retention of customers and tries to provide strategic implications for a firm to run a loyalty program. We classify purchase conditions into two types-acquisition vs. retention. Then we compare the effects of a coalition and a single-brand loyalty program on the purchase intention, under both the acquisition and the retention conditions. The result shows that the effect of the coalition loyalty program is stronger than that of the single-brand loyalty program under the acquisition condition. On the other hands, the single-brand loyalty program is more effective than the coalition loyalty program under the retention condition, at least for the minor brand.