by mistake

Meaning

This phrase means accidentally or without intending to do so. It is used to explain that an error was unintentional, helping to soften the impact of a blunder in a professional environment. It is neutral and polite.

Examples

• I sent the confidential spreadsheet to the wrong email address by mistake.

  I sent the confidential spreadsheet to the wrong email address by mistake.

• She deleted the backup files by mistake, but luckily we restored them.

  She deleted the backup files by mistake, but luckily we restored them.

• If you received this invoice by mistake, please disregard it.

  If you received this invoice by mistake, please disregard it.

• He signed the contract by mistake before reading the final terms.

  He signed the contract by mistake before reading the final terms.

• The system charged your account twice by mistake, and we are processing a refund.

  The system charged your account twice by mistake, and we are processing a refund.

Common Mistakes

• ✗ I deleted the file on mistake.

  ✓ I deleted the file by mistake.

  In English, we say 'by mistake' but 'on purpose'. Do not mix these prepositions.

• ✗ It was done by a mistake.

  ✓ It was done by mistake.

  Do not use an article ('a') in this fixed prepositional phrase.

Related Expressions

Practice

• I'm sorry, I must have taken your laptop charger ___.

  💡 A two-word phrase meaning accidentally.

  Show answer

  by mistake

• The customer was billed twice ___ due to a software glitch.

  💡 Opposite of 'on purpose'.

  Show answer

  by mistake