A cover letter for an internship is three paragraphs that decide whether your CV gets read or trashed. Most students treat it as a formality — they grab a generic template, change the company name, and send. Predictable result: recruiters skim in 8 seconds and move to the next CV. A letter that works does the opposite — it makes them want to read the CV.

This guide is the method used by Vocacia mentors — bankers, consultants, product managers, lawyers in current roles — when they help their own mentees draft letters that land internships at Goldman, McKinsey, BCG, Lazard, Google, L'Oréal, and others. It covers the structure that converts (the 4-paragraph canvas), how to open without falling into clichés, what to put in the body, how to close with a real opening, 5 downloadable sector-specific templates (finance, consulting, marketing, tech, law), the 8 mistakes that disqualify, and a before/after rewrite annotated by a mentor.

TL;DR — the 60-second version

A cover letter for an internship fits in 4 short paragraphs (300-400 words max). Paragraph 1: why this company specifically (reference to a recent project, not to a “strong culture”). Paragraph 2: why you (two concrete proofs with numbers or results). Paragraph 3: what you will bring to the team during the internship. Paragraph 4: the follow-up and the closing. No filler, no padding. The recruiter reads it in 30 seconds — every sentence counts.

The structure that converts: the 4-paragraph canvas

Before writing the first sentence, draw the canvas. This is what separates a letter that reads in 30 seconds (good) from a letter that reads in 90 (bad).

Total: 270-340 words, three quarters of a page in size 11. A longer letter is not a better letter; it's a less-read letter.

How to open a cover letter: the first sentence

The opening determines if the recruiter reads on. It's the sentence they see in 1.5 seconds. Three openings to ban, three that work.

Openings to ban (90% of candidates use them)

Openings that work

  1. The “project” opening: “Your acquisition of X in March 2026 made me reconsider what I want from my final-year internship. This is exactly the type of problem — Y meets Z — I want to work on.” Immediate company anchoring + signal of active research.
  2. The “person” opening: “Listening to [executive name]'s interview on the [name] podcast last month, I heard a sentence that captures why I want this internship at your company: [sentence].” Credible, personal, shows research.
  3. The “number” opening: “87% of candidates for your M&A internship will tell you about their interest in corporate finance. I'm going to tell you about the 13%: [specific angle].” Use carefully — can come across as arrogant if poorly executed.

The common thread: the first sentence is about the company, not you. You only arrive in paragraph 2.

What to put in a cover letter: the body that lands

Paragraph 2 — Why you

This is where 80% of candidates list their CV. Mistake. The recruiter already has your CV attached. What they want is two concrete proofs showing you can do the work asked.

Structure of a proof:

  1. Context (1 sentence): project, team, duration.
  2. The specific action you took (1-2 sentences).
  3. The numerical result or key takeaway (1 sentence).

Example (finance student applying to junior M&A):

“During my internship at Lazard last summer, I contributed to the financial modeling of a mid-cap divestiture in food & beverage. I built the DCF and trading-comps valuation model and prepared the strategic-analysis slides for the buy-side pitch. The transaction signed at €350M after a six-month process, and I learned what ‘rigor’ means in a real deal — every number in the model was challenged three times by the associate.”

This proof scores because it's specific, numerical, and points to a competence transferable to the future internship.

Paragraph 3 — What you bring: the bridge to their need

This is the paragraph other candidates skip and the one that flips the decision. You have 4 to 6 months of internship. What's the equation for the team? What will they gain that they couldn't without you?

Three angles that work:

The key point: this paragraph is about them, not you. Recruiters see very few candidates who think this way — that's what creates the gap.

How to close a cover letter: the ending that opens

80% of letters close with “awaiting your reply, please accept” — a passive formula that triggers no action. The closing must do two things: signal real availability and invite the next step.

Structure:

  1. One concrete availability sentence: “I am available for a conversation starting March 15, by video or at your office, depending on your preference.”
  2. One opening sentence: “I would be happy to discuss how I can contribute starting in the first weeks.”
  3. Standard closing: “Best regards” or “Sincerely.”

Variants by sector: in finance/consulting/law, stay formal (“Sincerely”). In tech/startup, “Best” or “Best regards” works. Match the culture you read in the company's communications (recruiter email signatures, careers-site tone).

5 downloadable templates by sector

Here are five letter skeletons adapted to the sectors most-applied-to by Vocacia students. Do not copy-paste — use as structure and adapt to your situation. A letter that looks like an internet template is disqualifying.

Template 1 — Investment banking internship (M&A, S&T)

Standard structure for a junior M&A application. Adapt names and numbers.

P1 (project): Your advisory on the sale of [Company] to [Acquirer] in [month] caught my attention — the complexity of the industrial carve-out and the speed of execution illustrate exactly the type of mandate I want to work on.

P2 (proof): A [school/program] student, I'm coming off a 6-month internship at [bank] where I built the DCF and trading-comps valuation model on three mid-cap industrial transactions. The main deal — a €350M divestiture — taught me the rigor of financial modeling under deadline and the coordination between M&A advisor, vendor due diligence, and legal counsel.

P3 (contribution): Over the six months of internship at your firm, I can take operational ownership of the comparables and precedent-transactions models and contribute to sector pitches — particularly in [sub-sector where the bank has a franchise]. My goal is to work toward a return offer for the analyst program in 2026.

P4 (follow-up): Available starting [date], I would be happy to discuss how I can contribute from the first weeks. Best regards.

Template 2 — Consulting internship (MBB, Big 4)

Standard structure for MBB or Big 4. The trap is generic “I love solving complex problems.”

P1: Your firm's report published in [month] on [sector theme] made me reconsider how traditional companies approach [topic]. I want to work on this type of question during my internship — not observe, contribute.

P2: A [program] student, I led an analogous case study during my 4-month internship at [client/company], where I analyzed segment-level profitability across [N] products and identified [numerical result] of optimization potential. The work was presented to the executive committee and led to [concrete decision].

P3: On a client case during the internship, I can contribute to the diagnostic phase (operational interviews, hypothesis structuring) and free up time on quantitative work for the consultants. My ambition is to learn your problem-solving methodology and client-facing storytelling, two skills I want to master before moving into consultant.

P4: I'm available starting [date] and would welcome a first conversation. Sincerely.

Template 3 — Marketing / communications internship

Marketing values creativity and impact measurement. Include numbers and concrete campaigns.

P1: Your campaign [name] launched in [month] is exactly the kind of work I want to learn to do — precise cultural anchoring, multichannel execution, measurable results. That's why your marketing internship interests me.

P2: During my internship at [company] last summer, I managed the launch of a [type] campaign on Instagram and TikTok for the French market. Reach of [number] impressions, [%] engagement rate, [N] qualified leads in 6 weeks. I learned to read analytics, adjust creative in A/B tests, and defend a media budget to the brand director.

P3: During the internship at your firm, I can take ownership of the social-first campaigns for the [market] segment and bring active monitoring of emerging formats (UGC, creator partnerships) that I've been tracking for 18 months. Goal: ramp up on omnichannel strategy.

P4: Available starting [date], I'd be happy to discuss how I can contribute. Best.

Template 4 — Tech / product internship

Tech values technical precision and stack/product alignment. Mention concrete projects on GitHub if relevant.

P1: Your launch of [feature/product] in [month] solves precisely the problem [X] I encountered as a user of the product. It's rare for a tech team to address this issue this way — I want to understand how you work.

P2: A [school] student focused on [domain], I shipped [project]: a [type] that [function], deployed on [stack], used by [N] users. Code on GitHub: [link]. I learned to iterate on real user feedback and arbitrate between velocity and technical debt.

P3: For the [PM/engineer] internship, I can take ownership of [type of task] and bring an applied user perspective — I've read your latest release notes and see two areas where my [stack/process] experience could accelerate iterations.

P4: Available starting [date]. Happy to jump on a first call if useful. Best.

Template 5 — Law internship (lawyer, in-house counsel)

Law values rigor, precise knowledge of the firm, and seriousness of the application. The tone is more formal than other templates.

P1: Your firm's representation in the arbitration of [case] in [year], as reported in [publication], illuminated for me how [precise legal point] can be handled. This expertise — at the intersection of [matter 1] and [matter 2] — corresponds exactly to the type of practice I want to develop.

P2: A second-year LLM student in [specialty] at [university], I completed a 4-month internship at [firm] where I contributed to drafting summary memos on [domain] and prepared exhibits for two litigation cases. This experience taught me writing precision and the rigor of collaborative work under deadline.

P3: I want to bring to your [specialty] department deep jurisprudential research capacity and rigor in case documentation. Long-term, my goal is to specialize in [domain] and your firm is one of the three in the country where this practice is most mature.

P4: I am available for an interview and attach my CV and academic transcripts. Sincerely.

8 mistakes that disqualify a cover letter

  1. Wrong company name. Happens more than you'd think — a botched copy-paste of the opening paragraph. Triple-check the name before sending.
  2. Generic letter “your industry-leading company.” Instant negative signal. If the same letter works for 5 companies, it works for none.
  3. Listing your CV in P2. The recruiter has your CV. Give them what's not in it: the why and the story behind the experiences.
  4. Skipping P3 (contribution to the team). 70% of letters skip this paragraph. It's the main differentiator.
  5. Spelling errors. One typo = letter rejected at 60% of consulting and law firms. Get two people to proofread minimum.
  6. Sloppy formatting. Readable font (Calibri, Garamond, Times), size 11-12, 2.5cm margins, header with contact info. No 4-page PDFs.
  7. Letter too long. Past 400 words, the recruiter jumps to the conclusion. Compress.
  8. Asking about remote work in the letter. Legitimate question, but not in the letter. Save for the interview.

Before / After — annotated rewrite

Before — generic version (90% of candidates)

“Dear Sir or Madam,

I am writing in response to your internship offer posted on LinkedIn. I am a Master's student in finance at HEC, and I am very interested in your industry-leading company. My academic background gave me strong skills in corporate finance and financial analysis. I completed several internships that taught me rigor and teamwork. I want to put my skills at the service of your company and I am convinced your firm is the right place for my professional development.

Awaiting your favorable reply, I remain, yours sincerely.”

Mentor commentary

After — rewrite (same candidate, same facts)

“Dear Sir or Madam,

Your firm's advisory on the sale of Eurosic to Gecina in March 2026 made me reconsider what I want from my Master's internship — the simultaneous execution of the carve-out and the due diligence in 4 months illustrates exactly the type of mandate I want to work on.

A Master's student in finance at HEC, I'm coming off a 6-month internship at Lazard where I built the DCF and trading-comps valuation model on a €350M mid-cap industrial divestiture. This experience taught me modeling rigor under deadline and the coordination between M&A advisor, vendor DD, and legal — three professions you have to make speak for a deal to close.

For my internship at your firm, I can take ownership of sector comparables models and market notes for the real-estate segment. My goal is a return offer for the 2026 analyst program — this ambition explains the rigor I bring to every file.

Available starting June 1, I would be happy to have a first conversation.

Sincerely.”

Why the After version lands

Cover letter for an internship with no experience: what to do

If this is your first internship and your CV is short, you can't invent experience. But you have other proofs: academic projects, association activities, side-projects. The secret is to treat them as professional experiences.

Three substitutes that work:

Recruiters value the ability to turn a project into a measured deliverable — whether it comes from an internship or a personal project. The key is to frame it as professional experience.

After sending: the follow-up that unlocks

You sent the application 10 days ago, no answer. What now? One well-done follow-up unlocks 1 application in 4.

When to follow up? 7 working days after the initial send if no timeline was announced; D+5 after the announced date if you were told “answer within a week.”

How to follow up? A short email (5 lines max) to the direct recruiter (LinkedIn to find their name). Three elements:

  1. Context recap (1 sentence): “Hi [Name], I applied on [date] for the [role] internship.”
  2. New information or recent event (1-2 sentences): “Since then, I saw you announced X — I wanted to know if that opens any opportunities on the team.”
  3. A simple question that calls for a 30-second answer (1 sentence): “Do you have an updated timeline for the process?”

What not to do: repeat your application in full, use emojis, hint that you have other offers to apply pressure. All these signals have the opposite effect.

The Vocacia AI tool to generate your letter

Vocacia provides a free cover letter generator (no signup, instant PDF export) that produces a first version based on your CV and the offer. Important: treat the output as a draft — not as the final version. Recruiters detect raw AI-generated letters in seconds (overly generic phrasing, repeated vocabulary).

Recommended workflow:

  1. Generate a first version with the tool to get the skeleton.
  2. Rewrite P1 entirely (your specific opening on the company).
  3. Replace P2 with your concrete proofs with numbers.
  4. Add P3 (contribution to the team) — AI tends to skip it.
  5. Get a mentor to review for one final iteration.

To get your letter reviewed by a mentor working in your target sector, book a 30-60 minute session — the difference between an acceptable letter and one that lands an interview.

FAQ — common questions

How long does it take to write a good cover letter?

First letter: 3 to 5 hours. Once you've mastered the structure for your target sector, expect 60-90 minutes per letter, including 30 minutes of company research. Prepare a master canvas you adapt — not copy-paste, a real canvas with paragraphs 1 and 3 rewritten each time.

Do I need to personalize for each company?

Yes, no exceptions. A generic letter signals to the recruiter that you're mass-applying — instant negative signal at 90% of premium firms. Minimum to personalize: P1 entirely, and at least 2-3 sentences of P3. Paragraphs 2 (proofs) and 4 (follow-up) can stay stable.

Cover letter or simple email?

If the offer asks for a letter, send a letter. If it says “email + CV is enough,” email. If nothing is specified, send an email with a short message (3-4 sentences) covering the key points and the letter as an attachment. This covers both audiences: the recruiter who reads the email quickly and the manager who opens the detailed letter.

Send the letter as PDF or Word?

PDF, always. Word risks layout corruption and signals a non-final send. File naming: Firstname-Lastname-Cover-Letter-Internship-Company.pdf. Not “Letter v3 final final.docx.”

Should I sign the letter manually?

No for digital application. Text signature (your name) is enough. A scanned manuscript signature looks dated and bloats the PDF unnecessarily. Save manuscript signatures for very traditional contexts (notaries, certain administrations).

What font and size to use?

Fonts: Calibri, Garamond, Cambria, Helvetica, Times New Roman. Avoid Comic Sans, Papyrus, and any fancy choices. Size: 11 or 12 for the body, 14 for your name in the header. Margins: 2.5cm minimum all around.

What if I don't have the recruiter's name?

Search LinkedIn: “[Company name] + Talent Acquisition” or “[Company name] + Recruiter.” If you find nothing, use “Dear Sir or Madam” — neutral and acceptable. Avoid “To whom it may concern” (formal, dated) or “Dear Director” (presumptuous).

How much time does a recruiter spend on my letter?

First read: 8 to 30 seconds. If the letter passes that filter, second full read of 60-90 seconds. That's why P1 (the opening paragraph) is critical — it determines whether the second read happens.

Recap and next step

A cover letter for an internship that lands an interview follows four principles: paragraph 1 about the company (not you), paragraph 2 with two numerical proofs, paragraph 3 about what you contribute to the team, paragraph 4 active with dated availability. Total: 270-340 words, on three quarters of a page.

The classic trap: spending 4 hours polishing the layout and writing generic phrases. The good time investment: 30 minutes of company research, 60 minutes of writing, 30 minutes of review by a mentor in role.

Use our free cover letter generator to start from a quality draft, then have it reviewed by a mentor working in your target sector — banking, consulting, marketing, tech, law. The difference between an acceptable letter and one that lands gets made in this last iteration. Once the letter is validated, read our guide on how to prepare for a job interview for the next stage of the process.