err on the side of caution

American  

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

idiom

1. 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.

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Etymology

Origin of err on the side of caution

First recorded in 1780–90

Example Sentences

See Examples For:

err on the side of caution

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

Meta says Instagram's new alerts - stemming from its analysis of user search patterns - may occasionally alert parents when there is no cause for concern and will "err on the side of caution".

From BBC ● Feb. 26, 2026

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

From The Wall Street Journal ● Nov. 11, 2025

I don’t know if it still hurts people’s feelings at that age to be thought of as older, but it’s better to err on the side of caution.

From "Saints and Misfits" by S.K. Ali