A cover letter has exactly one job: connect your strongest evidence to this specific role, in your own voice, in under 400 words. Every rule below serves that. If a sentence doesn't, cut it.
Fewer postings ask for one than five years ago, but when they do, most hiring managers read it — after the resume, and only if the resume passed. That ordering should shape your effort: a letter can't rescue a weak resume, but it can break a tie, explain a pivot, and demonstrate that you can write a coherent paragraph, which most of your competition cannot.
This skeleton has survived every hiring fashion because it mirrors how a reader's attention actually works:
| Paragraph | Contains | Sentences |
|---|---|---|
| 1. Hook | Role + company named, one line on why you | 2–3 |
| 2. Evidence | Your single most relevant achievement, with a number | 3–4 |
| 3. Fit | 2–3 skills from the posting, each tied to where you've used them | 3–4 |
| 4. Close | Why this employer, thanks, a next step | 2–3 |
Notice there's no "paragraph about my passion" and no restating your resume top to bottom. The letter adds what the resume can't hold: reasoning, motivation, and a hint of what you sound like in an email.
Your first sentence is the most-read line in the document. Compare:
The pattern: something specific to them, then something specific to you, ideally with a number in it. "I've used your app since 2021 and the 3.0 redesign is why I'm writing" beats "I am passionate about your company" in every test that matters.
Pick the achievement that most resembles the job's core work. If the role is about growth, your growth number; if it's operations, your efficiency number. State it plainly: "Cut order-to-ship time from 3.2 days to 1.4 days over six months." Then one sentence on how, because the how is what an interviewer will probe anyway. Enthusiasm is fine in the closing; evidence belongs in the middle.
Answer eight questions, pick a tone, and get a letter built on the four-paragraph skeleton — then edit it until it sounds like you.
Try the Cover Letter Generator →The last paragraph is where blast applications expose themselves. "I'm excited about this opportunity" could end any letter in America. "Since Northwind moved into healthcare data, I've been following the platform notes — that intersection is where I want to work next" could end exactly one. Close with a simple ask: you'd welcome the chance to talk. No need to promise a follow-up call you may not make.
250 to 400 words on one page, which lands at three or four short paragraphs. Past 400 words, skim rates fall off a cliff. If your letter runs long, the achievement paragraph is usually the one to keep and the adjectives are the first thing to cut.
Usually yes. When it's optional, most candidates skip it, so a short, specific letter is a cheap way to stand out, and some ATS platforms score applications higher with one attached. The exception: if you genuinely have nothing specific to say about the company, a generic letter is worse than none.
Something only this applicant could write about this company. Name the role, then hook with a specific: the exact problem in the posting, the moment you became a customer, the number you're proud of. Never open with "I am writing to apply for" — it restates the subject line and wastes your most-read sentence.
A majority do, per repeated surveys of recruiters and hiring managers, but they read them after the resume, and only if the resume cleared the bar. That ordering tells you the division of labor: the resume gets you screened in, the letter colors the decision, explains gaps and pivots, and shows how you communicate in prose.