How to write a cover letter

A good cover letter answers two questions a resume cannot: why this job, and why you. It is short, specific, and written for one posting. You do not need clever phrasing or a hook. You need to connect a few of your real accomplishments to what the role actually asks for, and to sound like a person rather than a template.

Do you still need a cover letter?

Often, yes. Plenty of applications still ask for one, and when a posting requests it, leaving it out can quietly cost you. Even when it is optional, a brief, specific letter gives you room to explain things a resume leaves flat: why you are drawn to this particular role, how your experience lines up, or why you are changing direction. If a posting explicitly says not to send one, follow that.

What should a cover letter include?

Most effective cover letters have the same four parts:

• A greeting. Use the hiring manager’s name if you can find it. “Dear [Name]” beats “To Whom It May Concern.” If you genuinely cannot find a name, “Dear Hiring Manager” is fine.
• An opening. Name the role and say, in a sentence or two, why it interests you and why you are a credible fit.
• A middle. Connect two or three of your real, relevant achievements to what the job needs. Show outcomes, not a list of duties.
• A closing. Thank the reader, point to your resume for the full picture, and say you would welcome the chance to talk.

How long should a cover letter be?

Keep it under one page — roughly 250 to 400 words, in three or four short paragraphs. A hiring manager may read dozens of these in a sitting, so a tight letter that makes its point lands better than a long one that restates your whole resume. If a paragraph is not earning its place, cut it.

How do you open a cover letter?

Lead with the role and a genuine, specific reason you are interested, not a generic windup. Skip “I am writing to apply for the position of...” — the reader already knows that. A line that names something concrete about the team, the work, or your own relevant track record does more in less space. Save the detailed evidence for the middle; the opening just earns you the next few sentences.

How do you tailor a cover letter to the job?

Read the posting and pick the two or three things it clearly cares about most. Then show where you have genuinely done those things, using the posting’s own language where it fits. One specific, true example that matches what they need is worth more than three vague claims. As with a resume, tailoring is choosing which real experiences to put forward — not inventing new ones to fit the description.

Should you explain a career change or an employment gap?

Yes, and the cover letter is the right place for it. A resume shows the dates; a letter lets you frame them in one or two honest sentences — what you were doing, what you took from it, and why you are moving toward this work now. You do not owe anyone a detailed personal account. A brief, matter-of-fact explanation reads as confidence, while a hidden gap reads as something to hide. You can see this handled directly in the career-changer cover letter example.

What should you avoid?

• Repeating your resume word for word. The letter should add context, not echo the bullet points.
• A generic letter sent to everyone. If it could go to any employer, it will not move this one.
• Claiming skills or results you do not have. It surfaces fast in an interview, and it is the one mistake there is no recovering from.
• Going long. Past one page, you are losing the reader, not winning them.
• Opening with “To Whom It May Concern” when two minutes of searching would turn up a name or a team.

A quick cover-letter checklist

• Addressed to a person, or at least the right team.
• Names the specific role and why it interests you.
• Two or three real achievements tied to what the job needs.
• Under one page; every paragraph earns its place.
• Mirrors the posting’s wording for things you genuinely have.
• Explains any gap or career change briefly and honestly.
• Sounds like you, not a template.

How ResumeHarbor helps

ResumeHarbor writes a cover letter to match a specific posting from the same reusable profile your resume is built from — the one you build by answering a few questions or import from an existing resume — so the letter and the resume tell one consistent, true story. You choose the tone and length, and you can rework it until it sounds like you. As with everything here, it draws only on what you have actually told us — it will not invent experience to fill the page, and it surfaces a real gap rather than papering over it.

See real examples on the cover letter samples, and pair this with the guide to writing an ATS-friendly resume and the resume examples by situation.

Questions this guide did not cover? See the frequently asked questions or email help@resumeharbor.pro.