A cover letter is a short, one-page document you send with your resume to introduce yourself to a hiring manager and explain why you are the right person for a specific job. Your resume lists what you have done. Your cover letter tells the story your resume cannot: why this role, why this company, and what you would actually bring on day one. After years of coaching candidates from my base in Zürich, I have watched a well-written cover letter turn a borderline application into an interview more times than I can count. This guide explains exactly what a cover letter is, when you need one, what goes inside it, and how to write one that a busy recruiter will actually read.
Do cover letters still matter? The data says yes.
What a cover letter actually is
At its simplest, a cover letter is a letter of introduction attached to your resume when you apply for a job, as Wikipedia defines it. University career centers describe it the same way: Purdue OWL calls it the document that "introduces you and your resume to potential employers," and Columbia University frames it as a one-page business letter submitted alongside your resume. It is not a summary of your resume, and it is not a formality. It is your one chance to speak directly, in your own voice, before anyone has met you.
Cover letter vs resume: the difference that matters
People confuse the two constantly, so here is the clean line. Your resume is a structured, scannable record of your experience, skills, and education. Your cover letter is a persuasive, personal argument for one specific role. A resume is written once and lightly tuned per application. A cover letter should be written fresh for each job, because its entire value is in being specific. If you want the full breakdown, read our guide on .
