The decoy effect
The decoy effect is when adding a third, deliberately inferior option changes which of the original two you prefer. The "decoy" isn’t meant to be chosen — it’s there to make one option look like obviously better value.
Why does the decoy effect happen?
We judge value by comparison, not in absolute terms. A decoy that’s clearly worse than one option (but not the other) makes that option "dominate," nudging us toward it.
Your preferences aren't fixed — change the menu and you change the mind without changing the options.
What does the decoy effect look like in real life?
- The Economist’s pricing: a print-only option priced the same as print+web made print+web the "obvious" deal.
- Small popcorn $4, large $7, medium $6.50 — the medium decoy sells the large.
- Three-tier SaaS pricing where the middle tier exists mainly to sell the top one.
How do you counter the decoy effect?
- Ignore options you’d never pick — don’t let a decoy frame the others.
- Evaluate each option against your needs, not against the other options.
- Ask whether the "great deal" only looks great next to a planted dud.
The deeper point
It’s proof your preferences aren’t fixed — they’re constructed at the moment of choosing, from whatever’s on the table. Change the menu and you change the person’s mind without changing the options they actually want.
Frequently asked
- What is the decoy effect?
- When adding a deliberately inferior third option changes your preference between the original two — the decoy exists to make one option look like clearly better value.
- What is the Economist pricing example?
- Offering print-only at the same price as print+digital made the combined option seem an obvious deal; the print-only "decoy" sharply boosted sales of the bundle.
- How do you avoid the decoy effect?
- Judge each option against your own needs rather than against the others, and ignore any option you’d never realistically choose.
Related
Keep reading
Projection bias
Shop hungry and you buy for a self who will never be this hungry again.
This bias distorts shopping & spending.
Go deeper
The book behind this idea: Predictably Irrational by Dan Ariely. Hear the whole thing free — start an Audible trial and your first audiobook is on the house.
Read the full summary of Predictably Irrational →
More canonical picks:
- Thinking, Fast and Slow — Daniel Kahneman
- The Art of Thinking Clearly — Rolf Dobelli
- The Great Mental Models, Volume 1 — Shane Parrish
- Poor Charlie’s Almanack — Charlie Munger
- Super Thinking — Gabriel Weinberg & Lauren McCann
- Seeking Wisdom — Peter Bevelin
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Cite this page
ReadGlobe. (2026). The decoy effect. https://readglobe.com/bias/decoy-effect/
"The decoy effect." ReadGlobe, 29 May 2026, readglobe.com/bias/decoy-effect/.
Primary source: Wikipedia
Editorial synthesis © ReadGlobe 2026, drawing on Kahneman’s Thinking, Fast and Slow, the Tversky–Kahneman research program, and the primary cognitive-science literature. · Last reviewed 2026-05-29.