Apply a 24-hour (or 72-hour) rule to non-essential purchases

Wait a fixed period before completing any unplanned purchase above a set threshold.

Why it works

Impulse purchases are driven by a hot, immediate motivational state — desire is highest at first contact with the item or idea and typically declines with time as the hot representation cools. A mandatory wait period outlasts the peak of the impulse, leaving the decision to a calmer state that better represents long-term preferences. The rule also gives competing considerations (budget, alternatives) time to surface.

How to do it

1. Set a threshold — for example, anything over $50 unplanned waits 24 hours; over $200 waits 72 hours.
2. Save the item to a wish list rather than a cart; this acknowledges the desire without purchasing it.
3. At the end of the waiting period, reassess from scratch: "Do I still want this and why?"

Evidence

The decreasing-desire effect over short time horizons is consistent with the hot/cool system model and with research showing that affective impulses decay faster than considered preferences. The specific rule is practitioner advice rather than a studied threshold. (mechanistic)

The 24-hour frame is a heuristic; the underlying mechanism (desire cools with time) is well grounded in psychology, but the "right" waiting period varies by person and item.

Common mistake

Spending the waiting period browsing reviews and imagining owning the item, which keeps the hot representation active and defeats the purpose of the pause.