Pink slip refers to the American practice, by a personnel department, of including a discharge notice in an employee's pay envelope to notify the worker of his or her termination of employment or layoff.[1] Receiving a "pink slip" has become a metaphor for the termination of employment in general. According to an article in The New York Times, the editors of the Random House Dictionary have dated the term to at least as early as 1910.
Pink slips came back into the news circa 2009, with the layoffs following the Wall Street crash.[1] The origin of the phrase is undetermined, and there is no evidence that termination notices are, or ever were, conventionally printed on pink-colored paper.[2] In the UK and Ireland the equivalent of a pink slip is a P45; in Belgium the equivalent is known as a C4.
The term pink slip may also relate to the fact that many applications (including termination papers) are done in triplicate form, with the dismissed employee receiving the pink copy (hence the pink slip).