Cold Email Copywriting Guide: How to Write Emails That Convert

Nikita Bykadarov 7 min read

“How to Write a Cold Email?”

This is one of the most complex parts of outbound – partly because copywriting is a skill that takes time to develop.

Still, we believe the message itself is EXTREMELY important. It often makes or breaks the campaign. Setting up your infrastructure is easy (especially with Maildoso!), and getting good deliverability is totally doable. But writing a strong email that gets a 20% reply rate? That’s a whole different level.

We’ve analysed thousands of cold emails sent by our clients (over 3,000!), added our own outreach templates, and brought in the experience of our team in both marketing and sales. The result? A guide to help you write a near-perfect email (or at least get pretty close).

Key Takeaways

  • Keep it short — aim for 5 sentences: hook, problem, offer, call to action, social proof.
  • Write about the reader, not yourself — less “we,” more “you.”
  • Cut spammy, templated phrases and run your copy through a spam checker.
  • Show real numbers and results instead of vague promises.
  • Sound human and confident, like a Slack message — clear and to the point.
  • Focus on solutions, not the reader’s failings.
  • Test several versions, keep the winner, then vary it slightly.

Keep it short

“Keep it short” is the golden rule for cold emails.

It always works – and it’s also the rule most often broken. There’s no strict character limit like “never go over 300 characters,” and there’s no magic number that guarantees success.

But here’s the idea: the more text you write, the more words your reader has to dig through.

We suggest fitting everything into 5 sentences:

  • a greeting, personalization or hook;
  • a quick mention of the problem;
  • your offer;
  • a call to action;
  • a bit of social proof.

Focus on what’s in it for the customer

One of the golden rules of good marketing copy is to help your customer, not talk about yourself or your product. No matter how great your product is, people care more about their own challenges – show how you can solve them, and they’ll pay attention.

Another rule for strong copy: use less “we” (“our product,” “our company”) and more “you” (“you’ll get,” “your results”).

Avoid spammy phrases

Let’s be honest – you probably get a bunch of cold emails every week too, right? They usually follow the same script, which makes them easy to spot. You can recognize a sales email from the very first sentence.

It’ll probably say things like “I’m reaching out because I saw…” or “We offer a solution that helps…” or “We’ve already helped companies like [name]…”

Sometimes, our brains are better at filtering spam than any algorithm. As soon as people see these kinds of phrases, they instantly think, “Yep, spam.”

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Share real results

Your message will be much more convincing if, instead of just promising results, you share what you’ve already done – include real numbers and examples.

Talk like you would in Slack

Slack messages are a great example of how to write cold outreach, and here’s why:

You talk to coworkers with respect, but as equals. You don’t apologise for “taking their time,” and you don’t say things like “we’d be grateful even for a no.” Your tone is confident and professional, and cold emails should be the same.

Slack messages get to the point. They’re short and clear. Cold emails should be 3-5 sentences max.

Even in big companies, work chats sound human. When someone reads your message, they should feel like a real person wrote it.

Respect your reader

Sometimes people write cold emails like: “Are your sales tanking and your job on the line? Then this is for you…” or “Top 5 reasons you’re a terrible salesperson.”

This kind of messaging assumes something is wrong with the reader – they’re bad at their job, inexperienced, or just clueless. That kind of tone can feel insulting, and it’s best to avoid it.

Instead of focusing on problems, focus on solutions: not “5 reasons your website sucks,” but “5 ways to make your site better.”

Always test different versions

Even if you write a great cold email that follows all the rules, is that enough to make it work? Not really.

We recommend testing different versions and ideas – maybe one focuses on what the client gets, another on what worked for a similar company, and a third on how the product works.

You can run up to 5 different versions at once, check results in 2–3 days, and keep the one that performs best.

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Book a 20-minute call with our deliverability team.