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

Employers sometimes err on the side of caution, fearing lawsuits, and try to avoid terminating anyone on a job-protected leave.

From The Wall Street Journal ● Aug. 4, 2026

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

Generally, state laws don’t specify which material might be “harmful,” leaving many educators to err on the side of caution.

From Los Angeles Times ● Dec. 12, 2024

"They know you are here. Whether any will be bold enough to enter Chataya's in the guise of patrons I cannot say, but I find it best to err on the side of caution."

From "A Clash of Kings" by George R.R. Martin