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

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

From The Wall Street Journal • Nov. 11, 2025

“Many people struggle to switch off a ‘savings mindset’ and err on the side of caution which can result in them failing to make the most of their money in retirement,” according to Fidelity International.

From MarketWatch • Oct. 15, 2025

Ofsted's broad criteria for reporting can mean nursery workers "err on the side of caution", the Early Years Alliance says.

From BBC • Apr. 6, 2025

Doctors often give antibiotics to err on the side of caution, but that’s not recommended unless there’s evidence of a bacterial infection; overuse of the drugs can exacerbate the development of antibiotic resistance.

From Science Magazine • May 1, 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