Cover letter: how to write one that gets read

A cover letter does not repeat your CV: it explains why you and why this company, in less than a page. Here is the structure, the tips that matter most, a full example and a checklist to review it before you send it.

When you need one and when you do not

If the ad asks for a cover letter, always send one: leaving it out means not following an instruction. If it does not, a letter helps when there is something your CV cannot say on its own: a change of sector or country, a gap in your career, a requirement you only partly meet or a real connection with the company.

When nobody asks for it and your CV already answers the ad, a generic letter adds nothing. That time is better spent tailoring the CV.

The four-paragraph structure

A letter that can be read in a minute follows a fixed order. Each paragraph answers one question:

Opening: which role you are applying for and, in one sentence, why you fit.
Why you: two achievements from your experience that match what the ad asks for, with figures if you have them.
Why this company: something specific about it (a product, a market, a project) and what you would bring there.
Close: you are available to talk, without pleading or repeating what came before.

The tips that matter most

Address a person if you know who is hiring. If not, the team, never “To whom it may concern”.
Between 200 and 350 words. If it runs past a page, half of it can go.
Use the ad's wording for things you really did, just as you do in your CV.
Tell what the CV only lists: the context and the result of an achievement, not a list of duties.
Match the tone to the sector: more formal in banking or the public sector, more direct in tech or startups.
Check the company name and the job title. A letter that names another company is binned on the spot.
Send it as a PDF, with the same design and font as your CV.

A complete example

Sample person, made up. The ad: digital marketing manager at an online sports retailer.

Dear Trailhead Sports marketing team,

I am applying for the digital marketing manager role. I have spent six years running paid campaigns for online shops, the last two with my own budget.

In my current role I restructured our Google Ads and Meta campaigns by product category and we cut the cost per sale by 22% in a year. I also built the GA4 dashboard the whole sales team now uses to decide what to promote each week.

I have followed Trailhead Sports since you launched your mountain range. Your ad mentions growing in Ireland, and I launched that same market for my current employer: I know its costs, its seasons and what does not work there.

I would be glad to talk about how I would approach it with you. Thank you for your time.

Anna Example

Mistakes that backfire

Repeating your CV in prose, job by job.
Talking about what the company can do for you rather than what you can bring.
Adjectives without facts: “proactive, results-driven team player”.
The same letter for every job, with only the company name swapped.
Inventing or inflating an achievement: it shows at interview and undoes everything else.

With AI, without making things up

An AI tool can structure the letter and tailor it to each job ad, but only with what you actually did. If the letter mentions an achievement, a figure or a tool that is not in your experience, it is a risk with your name on it.

Frequently asked questions

How long should a cover letter be?

Under one page: 200 to 350 words, in four paragraphs. Recruiters read it in a minute or not at all.

What should a cover letter include?

The role you are applying for, two real achievements that match what the ad asks for, why that specific company, and a short close. Do not repeat what the CV already says.

Should I send a cover letter if the ad does not ask for one?

You do not have to. It helps when there is something your CV does not explain on its own, such as a change of sector or a requirement you only partly meet.

Who do I address it to if I do not know the name?

The team (for example, “Dear Marketing team”) or whoever signs the ad if it is shown. Avoid “To whom it may concern”.

Can I use the same cover letter for several jobs?

The structure, yes; the content, no. The paragraphs on why you and why this company change with every ad.