How to write a cover letter that gets read

Some hiring managers read every cover letter and some skip them, and you can't tell in advance which kind is reading yours. That uncertainty is the reason to write one that's short, specific, and quick to read. A good cover letter makes one or two points the resume can only hint at, like why you want this job, how your experience connects to it, or what explains an unusual history.

This Purzue guide covers when to send a cover letter, how long it should be, and what goes in each part. It ends with the mistakes that make a reader stop partway through, and how to catch each one before you send.

When to send one

If the posting asks for a cover letter, send one every time, since leaving it out can take you out of the running before anyone reads your resume. If the application makes it optional, send one when you have something to add. Good reasons include a career change, a move to a new city, a referral from someone at the company, a gap you'd like to explain briefly, or a specific reason you want to work for this employer.

If the application system has no place to attach or paste a letter and the posting doesn't mention one, you can usually skip it. A short note in an email or a LinkedIn message to the hiring manager can do the same job later, once you know who that is.

Length and format

Aim for 250 to 400 words in three or four short paragraphs, which fits on one page with room to spare. Use the same header, font, and contact details as your resume, so the two documents look like a set. Save it as a PDF unless the posting asks for something else, and if the application gives you a text box, paste the letter in as plain text and check the line breaks.

Address the letter to a person if you can find the right name in the posting, on the company's site, or on LinkedIn. "Dear Hiring Manager" is fine when you can't. "To whom it may concern" reads as dated, and guessing at a name you aren't sure of is riskier than leaving it generic.

The opening paragraph

Name the role and give your strongest reason for being a fit in the first two sentences. If someone referred you, say so here, since it's often the most useful thing in the letter. Skip openers like "I am writing to express my interest," which use up the reader's attention without telling them anything.

The middle, with one or two proofs

Pick the two requirements from the posting that matter most and that you can support best, and give a short, specific example for each. Each example should say what the situation was, what you did, and what happened as a result, in three or four sentences. This is the same structure as the STAR method for interview answers, in a shorter written form.

Avoid retelling your resume line by line. The letter's job is to connect your experience to this employer, so mention something specific about the company or the role, like a product, a goal stated in the posting, or a change the team is going through, and say why it matters to you. If you've worked out which requirements to focus on while tailoring your resume, use the same list here.

The close

End with a sentence that restates your interest in the role, a note on your availability or start date if it's relevant, and a thank-you. Keep it to two or three sentences. A plain close like "I'd welcome the chance to talk about the role, and I'm available for a call any weekday" is enough.

Mistakes that get a letter skipped

A copy-and-paste error, such as another company's name or a role you applied for last week, is an easy way to lose a reader, because it tells them the letter wasn't written for them. Read the letter once more with fresh eyes before you send it, and check every proper noun.

Other common problems are length, a generic opening, and a letter that's mostly about what you want from the job. If you're explaining a gap or a career change, give it a sentence or two and move on to what you bring. If you're sending work samples or a video, say in one line what each one shows, and the guide to video and portfolio attachments covers when those help. Hiring managers who look you up after reading the letter will often land on your LinkedIn profile, which the LinkedIn profile checklist helps you get ready.