Retailers use many different marketing promotions to increase sales and profits. These promotions include price reductions, coupons, cash mail-in rebates, free gift cards, and buy-one-get-one (BOGO) discounts. The type of promotion used results in different outcomes for demand, profit, average price, consumer surplus, and sales taxes collected. We perform comparative analysis of these five promotions and their outcomes. We show that for the same discount amount, price reductions result in the lowest average price. For products with weakly diminishing consumer utility and low consumer stockpiling, BOGO promotions result in the largest demand, profit, consumer surplus, and taxes collected. Cash mail-in rebates may result in large profit and taxes collected, but they perform poorly in terms of average price paid and consumer surplus. We also find that a retailer offering a delayed incentive (i.e. gift cards and mail-in rebates) offers a larger reward but provides lower consumer surplus than when offering an immediate incentive (i.e. price reduction and BOGO). In a segmented market with a price-insensitive consumer segment, immediate incentives have the disadvantage of allowing price-insensitive consumers arriving during the promotion to obtain the discount, which reduces the discount effectiveness. The addition of more retailer objectives to maximizing profit, such as demand maximization or consumer surplus, increases the effectiveness of immediate incentives. We also provide a framework for estimating the important parameters for evaluating promotion effectiveness using readily available transactional data and examine its accuracy using a simulation experiment.