err on the side of caution

American

[er on thuh sahyd uhv kaw-shuhn, ur] / ˈɛr ɒn ðə ˈsaɪd əv ˈkɔ ʃən, ˈɜr /

idiom

to reduce risk by planning or acting more carefully than might seem absolutely necessary.

Budget for all your known expenses, but err on the side of caution by also allowing funds for unforeseen circumstances.
Sorry, but I removed your image from the thread—it’s probably not offensive, but I always err on the side of caution with such things.

Etymology

Origin of err on the side of caution

First recorded in 1780–90

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Even if we can’t be sure something is conscious, we might err on the side of caution by assuming it is – what philosopher Jonathan Birch calls the precautionary principle for sentience.

From Science Daily • Jun. 5, 2026

People don’t know how long they will live, so they err on the side of caution.

From MarketWatch • Apr. 16, 2026

Leaders’ first instinct was to err on the side of caution.

From The Wall Street Journal • Nov. 11, 2025

Meister wants the sport to err on the side of caution and create change to save pitchers’ arms.

From Los Angeles Times • Jul. 20, 2025

Knowing that the horse, when forced, tended to become obstreperous, Pollard may have decided to err on the side of caution and advise Workman to withhold the whip.

From "Seabiscuit: An American Legend" by Laura Hillenbrand

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023