Stacked (vs single) discounts work better

📝 Context

Topic: Promotions | Pricing
For: B2C
Research date: December 2025
Universities: Bentley University

You’re shopping online for a new pair of sunglasses and come across the same model on sale on different sites:

1. Aviator-style sunglasses: 35% discount

2. Aviator-style sunglasses: 15% discount + 10% Daily Deal discount + Sign-up for our newsletter for a 10% discount today

Although they’re both the same discount (35%), here’s why science says you’re more likely to choose the second option.

P.S.: Find more easy-to-apply techniques to optimize your promotions in our Science-based Playbook of Pricing & Promotions

📈 Recommendation

Unless you’re offering a huge discount, split your discount into different parts your customers can stack together (e.g. 15% off in-store discount + 10% off welcome discount for new customers + $25 in-store credit).

Make sure stacking is easy for customers to use (apply some automatically or give clear steps to follow), or people won’t do it. 

People will be more likely to engage with the discount and consider buying.

🎓 Findings

• People are more likely to engage with a discount and want to buy the item if the promotion is stacked (e.g. 10% new customer deal + 10% special sale) compared to a single discount of the same amount (e.g. 20% discount).

• As part of a series of 6 experiments and an analysis of over 9,000 deal posts, researchers found that people:

  • Had 15.8% higher shopping intentions when a 25% discount was split into 4 stackable parts.

  • Gave a stacked deal:

    • 66.3% more views

    • 52.7% more upvotes

    • 52.3% more comments 

  • Thought a deal with 4 stacked discounts, compared to a single discount: 

    • Was 33.1% more unique

    • Gave 20.7% higher feelings that they were smarter shoppers 

• People were more willing to buy regardless of the type of stacked discounts offered (e.g. percentage off or $5 off)

• The effect was:

  • Weaker when people felt stacking took too much work.

  • Stronger when the overall discount offered was smalle

🧠 Why it works

• Being able to stack different discounts together is rare, making us feel the promotion we’re getting is more valuable.

• When we’re able to combine different (e.g. a coupon via email plus a discount from a particular credit card) we feel like we’re getting more value from a promotion, making it more attractive.

• We value stacked discounts more because of the extra effort it takes to put the discounts together, just like we’re more likely to redeem a discount when we need to complete a small task (e.g. filling in a CAPTCHA) to access it.

• Since a stacked deal seems rarer, it also creates a sense of urgency compelling us to act fast so that we don’t lose the deal.

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✋ Limitations

• Stacking discounts was less effective when high discounts were offered (e.g. 65% vs. 25%), but it’s unclear where exactly this drop-off happens.

• People did find stacking discounts more complex than applying a single discount, but it’s unclear if there’s an upper limit to stacking discounts (e.g. 8 coupons at once) after which people find it too complex to put together.

👀 Real-life example

Health supplements brand AG1 offers large discounts on purchases of their supplement packages.

❌ Issue: AG1 offers an automatically applied large discount, without any breakdown of the discount.

✅ Solution: AG1 can make their bundle more attractive to customers by:

• Breaking the overall discount into components so it feels stacked (e.g. 15% sale on item + 10% welcome gift).

• Making the design of their product packaging look more complex to increase how much people would be willing to pay for the bundle.

• Give vouchers for low-value free gifts (e.g. scoop and shaker) instead of giving the gifts directly.

• Offer a coupon equivalent to the cost of shipping instead of free shipping, to increase sales without increasing their rate of returns.

🔍 Study type

Online experiments and market observation (analysis of 9,000+ US-based posts scraped from slickdeals. net)

📖 Research

One of a kind: How stacked discounts make customers feel smart. Journal of Retailing (December 2025)

🏫 Researchers

• Wenting Zhong. Bentley University.

• Lan Xia. Bentley University

Remember: This is a new scientific discovery. In the future it will probably be better understood and could even be proven wrong (that’s how science works). It may also not be generalizable to your situation. If it’s a risky change, always test it on a small scale before rolling it out widely.

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