Upselling/Cross-selling
What it is
Leveraging the commitment momentum of an existing purchase decision to increase the total transaction value.
How it works
Real-world examples
- •"Would you like to supersize that?" adding 30% to a fast food order.
- •E-commerce "frequently bought together" suggestions adding items at checkout.
- •Car dealerships presenting extended warranties, protection packages, and accessories after the main purchase is agreed.
Ethical guidelines
Suggesting a relevant add-on the customer would plausibly want is service. It becomes manipulation when add-ons are pre-selected, hidden in the checkout flow, or pushed regardless of fit.
- ●Upsells should provide genuine additional value, not just extract more money.
- ●Presenting upsells at the moment of maximum commitment is strategically timed to bypass deliberation.
- ●Customers should never feel pressured or tricked into spending more than they intended.
How to defend against it
- ►Set your budget before entering a purchase situation and stick to it.
- ►Treat every upsell as a separate purchasing decision — would you buy this item independently?
- ►Say "I'll think about it" to any add-on presented during checkout and evaluate it later.
From the Defense Playbook
Fix your criteria, budget, walk-away point, or answer in writing before you see the offer, the anchor, or the pressure, so that the decision is made by the cool version of you.
Before weighing a recommendation, find out what the person making it gains if you say yes (commission, funding, votes, attention, status), and adjust how much independent confirmation you require accordingly.
On any checkout, sign-up, or consent screen, read each checkbox and toggle before you continue, noting whether it is already ticked and whether ticking means yes or no, because defaults and confusing wording are how extras, marketing consent, and data sharing are obtained from people who never chose them.
Calmly repeat the same short statement of what you want or will not do, in the same words and tone, as many times as it takes, without being drawn into answering each new argument.
Every playbook entry states how strong its evidence is and when not to use it. Browse the full playbook.
References
- Freedman, J. L., & Fraser, S. C. (1966). Compliance without pressure: The foot-in-the-door technique. Journal of Personality and Social Psychology, 4(2), 195–202The commitment momentum the entry describes: having agreed to an initial request, people were substantially more likely to agree to a larger follow-on request (the foot-in-the-door effect), which is the sequence an upsell after a purchase decision relies on.
- Tversky, A., & Kahneman, D. (1981). The framing of decisions and the psychology of choice. Science, 211(4481), 453–458 · link'Each additional yes feels small relative to the original purchase': the jacket-and-calculator problem showed that people evaluate a fixed sum relative to the size of the purchase it is attached to rather than in absolute terms, so an add-on looks cheap beside a large base price.
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