By accident or on accident – which one is correct?

Prepositional phrases can be confusing! If you’re wondering whether it’s by accident or on accident, here’s a short explanation of why you may have seen both and which one you should choose.

by accident or on accident? Which form is correct meaning definition correct form difference examples

By accident or on accident – the correct form

The two adverbs mean that something is done unintentionally. Statistically speaking, on accident is barely used, and when it is, it appears in informal spoken language, never in formal writing. More often than not, it is considered a mistake. This leaves us with the only proper versionby accident. Keep reading to find out why this phrase might have gotten corrupted over time.

The origins of on accident

The incorrect form of on accident is a mistake that originated in spoken English. Some authors claim that it came from speakers trying to match opposing phrases. The antonyms of by accident include two phrases similar in structure: by design and on purpose, meaning that something was done intentionally. Google’s Ngram data shows that the phrase on purpose has been more popular than by design overall, so speakers might have wanted to use the same preposition to form its incorrect opposite – on accident.

Synonyms of by accident

  • by chance
  • by mistake
  • unknowingly
  • inadvertently

Now that we know which version of the phrase is correct, let’s look at how it’s used in some real-life examples.

By accident or on accident? Now it’s all clear! Examples from literature

Many geologists don’t understand this field. There’s a feeling of ‘well, if hydrogen was there, wouldn’t major oil companies have found it already’? But they weren’t looking for it. Most hydrogen discoveries have been by accident.

Jillian Ambrose, The Guardian – 12 Aug 2023

“It’s not by accident” Ellison said, highlighting technology investments and his stores’ more rural and suburban locations as factors that help reduce shoplifting and organized retail crime.”

Dominick Reuter, Business Insider – 15 Sep 2023

Written by

She is a translator and EFL teacher with an MA in English studies, who dabbles in writing, subtitling and academic proofreading. When not pondering the complexities of linguistic correctness, she enjoys DIY, cycling and playing any type of guitar she can lay her hands on.