Before you write anything
A cover letter is not a resume in prose. If you just rewrite your resume as paragraphs, the hiring manager will skip it and read the resume itself, which is faster. The cover letter's one job is to contextualize your resume for this specific role — to tell the hiring manager, in plain language, why you are the right application to pull out of the pile.
That means every cover letter should answer three questions, in order:
- Why this company? Something specific about the company, team, or product — not flattery, not their Wikipedia summary.
- Why you? Two or three concrete achievements from your resume that map to the role. Not your whole resume. Two or three.
- What's the next step? A specific ask (a call, a code review, a portfolio walk-through), not a generic "I look forward to hearing from you".
The three-paragraph structure
The classic structure — which works in 80% of cases — is three short paragraphs, ideally under 400 words total. Some roles justify a fourth paragraph. Almost none justify five.
Paragraph 1: why this role, why this company
Open with a concrete reason you're applying to this specific role at this specific company. One sentence is enough. Follow it with one sentence that previews your most relevant credential.
Good: "I was drawn to the Senior Backend Engineer role at Lattice because your recent engineering blog post on reducing review-cycle lag described exactly the class of problem I spent the last 18 months fixing at Zendesk — where we cut review-service P95 latency from 420ms to 180ms."
Bad: "I am writing to express my strong interest in the Senior Backend Engineer role at your esteemed company. I believe my skills and experience would be a great fit for this position."
The bad version is generic enough that you could paste it into any application. The good version could not be pasted — it references a specific company post and a specific number from the applicant's resume. That specificity is the entire point of a cover letter.
Paragraph 2: proof
Pick two or three achievements from your resume that map to the hardest requirements in the job description. Do not restate your whole resume. Do not list six things. Pick the two or three that are the strongest evidence for this specific role and develop them in one or two sentences each.
The rule of thumb: every claim in this paragraph should be traceable back to a specific bullet on your resume. If it isn't, it reads as vague.
Paragraph 3: why them, now
This is where most cover letters fail. The default is to write something generic about the company's mission. The better move is to name one specific thing you want to contribute to — a product surface, a technical problem, a strategic moment. It signals that you read past the job description.
Paragraph 4 (optional): close with a specific ask
Instead of "I look forward to hearing from you", propose something specific: a 20-minute call, a take-home review, a walk-through of one of your past projects. The shift is small but it reads as confident.
The first sentence is everything
Recruiters spend roughly six to twelve seconds on a cover letter before deciding whether to keep reading. The first sentence has to earn the second one. Three opener patterns that work:
- The matched-problem open: "Your posting describes X — that's the exact problem I spent the last N months solving at Y."
- The referenced-artifact open: "I read your team's [blog post / case study / conference talk] on X, and it mirrors work I did on Y."
- The measurable-result open: "At Y, I [verb] [measurable outcome], which is why the [specific role] at your company caught my attention."
What doesn't work: "I am writing to apply for…", "As a passionate and detail-oriented professional…", "I was excited to see your posting for…", and any variation thereof. They occupy space and say nothing.
Phrases that signal weakness
A short list of phrases that experienced hiring managers have learned to read as filler. Deleting them instantly tightens a cover letter:
- "I am passionate about…" — passion is not a credential. Prove interest, don't claim it.
- "I believe I would be a great fit…" — fit is the reader's judgment, not yours to assert.
- "As a recent graduate…" — true for everyone from your class. Pick a specific project instead.
- "Team player", "hard worker", "detail-oriented" — cost nothing to say and mean nothing without evidence.
- "In today's fast-paced world…" — adds zero information.
How long should it be?
250 to 400 words. Three or four short paragraphs. One page is the absolute ceiling — anything longer and the reader stops before the end. If you think you need more space, the fix is almost always to cut a sentence, not add one.
Should you address it to a specific person?
If the posting names a hiring manager, address them by name. If it doesn't, "Dear Hiring Manager" is fine — better than guessing wrong. Don't use "To Whom It May Concern"; it reads as dated.
Spending 15 minutes on LinkedIn to find the hiring manager and addressing them by name is a real signal of effort. If you do this, don't mention that you looked them up — it creates a weird dynamic.
When to skip the cover letter entirely
If the application form says "cover letter optional", most applicants skip it. That's a mistake for roles where writing matters — PM, marketing, design, any communication-heavy function. For pure engineering roles, especially at companies that explicitly say they don't read them (some well-known SF startups say this), you can genuinely skip it.
When in doubt, write it. A tight 300-word letter takes 20 minutes and can separate two otherwise-identical candidates.
One final check before you submit
Read the letter out loud. Any sentence that feels awkward to speak will feel awkward to read. Cut anything you stumble over. That single pass eliminates about half the bad sentences in an average cover letter.
Then run it through ATS logic: do the first two paragraphs contain three or four of the keywords from the job description? If not, add them naturally. Recruiter systems scan for keyword overlap as a first filter.