How to write a cold email that gets opened and answered

What is a cold email?

A cold email is a one-to-one message to someone who hasn’t heard from you before, sent to start a relevant business conversation: a sales meeting, a partnership, a job, an introduction. It isn’t a newsletter, which goes to people who subscribed, and it isn’t spam, which goes to everyone. The difference is targeting: a cold email is written for one person, or for a small group with the same problem, and it can explain in one sentence why it went to them.

When done properly, cold mailing can be one of the most successful marketing strategies. There are only a few things you need to remember while setting up your cold emails.

Right targeting

Do your research about the people you’re sending an email to. Be sure that they are truly the ones who can make a business decision and buy your product. It’s far easier with the right tools doing this job for you. Group your targets by location, industry, company size or job position, and write relevant emails for each of those groups. It’s the wrong targeting that leaves most emails unopened. A simple change in targeting can make all the difference when it comes to engagement.

Then look for a reason to write now. A good cold email rests on one real signal: the company is hiring for a role your product supports, it has entered a new market, launched a product or changed its leadership, or the person has published an article or given a talk. One specific signal is worth more than a list of facts proving you studied their profile. Company websites, job ads, press releases, case studies and interviews are the usual sources, and this research is where most of successful prospecting happens.

You may come across the “30/30/50 rule” of cold email. Coursera describes it as 30% of success coming from researching the right audience, 30% from the email itself and 50% from following up. The numbers add up to 110%, so read it as emphasis rather than math: who gets the email and whether you follow up matter at least as much as the writing.

Create a catchy subject line

Do you know why your cold emails are not opened? They may have landed in the spam folder, or got lost in the receiver’s mailbox. It happens, because your prospects get hundreds of emails. But excluding those reasons, they might simply be too boring to open, even when noticed. Try to catch the gaze and attract prospects with a creative, catchy subject line. You can also use emoji when appropriate, although in B2B outreach a plain line that looks like a colleague wrote it usually fits better.

Avoid being manipulative and aggressive, as this only worsens the chances of getting your email opened. Don’t try to trick the reader, because they might feel deceived, and that’s the feeling you don’t want to cause in a prospect. Use CTA phrases in the title. A simple “Can we talk?” at the end of the subject can persuade the reader to open the email and read the text.

Data on cold subject lines points the same way. Belkins, a B2B outreach agency, analyzed more than 5.5 million cold emails sent in 2024: subject lines of two to four words had the highest open rate (46%), longer lines did worse as they grew, and personalized subject lines beat generic ones, 46% against 35%. Open rates are inflated by privacy features, so treat the exact numbers with care, but the direction is clear: short, specific and about the reader.

Subject lines that tend to work follow a few patterns:

• A specific reference: “Your talk on onboarding at [event]”.
• A question about their situation: “Hiring 3 SDRs in Austin?”
• An outcome in their terms: “Fewer returns at [Company]”.
• A mutual connection: “[Name] suggested I write”.
• A small, clear topic: “Question about [Company]’s checkout”.

Avoid “Re:” or “Fwd:” on a first email, since it pretends to continue a thread that never existed, along with fake urgency, ALL CAPS, clickbait the body doesn’t deliver and any subject that could go to anyone. Under the US CAN-SPAM Act, a deceptive subject line isn’t only bad copy, it’s a violation.

Right personalization

Nobody is impressed by seeing their name in the subject line anymore. Right personalization is key, but it’s far more than the recipient’s name put inside the text. Of course, you can’t write a personal letter to everybody, but sending out one copy of the same information won’t bring you any profit either.

Instead, personalize the parts of the content that matter, via Marketing Automation systems. The program decides who receives which version. You can personalize on the basis of industry, role or location, whichever is the most relevant to the message you’re trying to convey.

Remember that the connection between the reader and you must be based on something you two have in common. Try to find it through thorough research and use it with the help of well-set automation processes.

In practice, personalization works in layers. The first line is written for one person and refers to their signal. The middle, the problem you solve and the proof, is shared by everyone in the same segment, for example heads of operations at mid-sized food manufacturers. The ask is the same for all. That way each email feels personal without being written from scratch.

AI has made the generic version cheap. Tools now turn a name, a title and a company into thousands of grammatical, “personalized” emails, and recipients have learned to spot them. Use AI for research and drafts: summarizing a company’s news, suggesting angles, tightening a paragraph. Then check every fact, delete generic praise (“I love what you’re doing at…”) and read the email aloud. If you wouldn’t say it to the person, don’t send it.

Shorter is better

Remember that nobody has time to read long emails. Try to be as direct as possible, without pouring many words into the message. Carefully think about what you want to achieve by sending the email. Do you want to tell your reader about new content on your website? Great! Be sure that your email is exactly about that. Don’t put your company’s history in there, because no one wants to read about it in an email. Efficient communication rarely needs to be inflated. Stick to the relevant facts and the most needed information.

How short is short? Boomerang analyzed more than 40 million emails in 2016, all kinds of email rather than only cold ones, and found that messages of 50 to 125 words got a reply more than half of the time, more often than shorter or longer ones. For a first cold email, that range is enough to say why you are writing and what you offer. A structure that fits in it:

• An opening line about them: the signal and why it caught your attention.
• The problem it usually brings, in their words, and one sentence on how you solve it.
• One piece of proof: a result for a similar company, with a number if you have one.
• One small ask: a yes-or-no question or 15 minutes next week, not a 45-minute demo.
• A plain signature: name, role, company and one link, with no banners, quotes or heavy HTML.

Here is how that looks in practice. It is an illustration of the structure, not a template to copy word for word:

Subject: Returns at [Company]

Hi Anna, I saw that [Company] now ships to Germany and Austria. Cross-border orders usually bring more returns, and many support teams still handle them by hand. We automate return labels and refunds for online shops of your size; [Client] cut the time spent on each return by [X]% in three months. Would a two-minute video of how it works for them be useful?

Best, Tom Nowak, Head of Sales, [Your company]

Follow up, and add something each time

A first email is easy to miss in a busy week, so plan a short sequence before you send it. Two or three follow-ups are enough for most B2B outreach, spaced about a week apart and sent in the same thread. Each one should add something: a customer result, a different angle on the problem, a useful resource or a simpler ask. “Just following up on my last email” gives nobody a reason to answer. Stop the sequence as soon as the person replies, and end it with a short, polite message that closes the loop.

Make sure the email arrives

A cold email that lands in spam doesn’t get opened, whatever the subject. Mailbox providers have tightened the rules. Since February 2024, Gmail has required every sender to authenticate with SPF or DKIM and to keep the spam rate below 0.3%, and a sender that has once sent about 5,000 messages a day to Gmail is permanently treated as a bulk sender, with DMARC and one-click unsubscribe required. Outlook.com has applied similar rules to high-volume senders since May 2025.

• Send from a real person’s mailbox on your company domain, with SPF, DKIM and DMARC set up. Many teams use a separate domain for outreach, so a mistake doesn’t hurt the main one.
• Warm up new mailboxes and keep the daily volume low: dozens of emails per mailbox, not thousands.
• Verify addresses before sending, because bounces and spam traps damage your reputation fast.
• Write in plain text, with one link at most and no attachments in the first email.
• Track replies and meetings booked, not opens, which privacy features make unreliable.

Is cold emailing legal?

In the US, yes, if you follow CAN-SPAM. The law doesn’t require prior consent, and it makes no exception for business-to-business email: every message needs honest sender details and an honest subject line, your postal address and a clear way to opt out, honored within 10 business days.

In Europe, the answer depends on the country and the recipient. The EU ePrivacy Directive requires prior consent for marketing emails to individuals and leaves business addresses to national law. Germany requires prior express consent for advertising emails to any recipient, companies included. The UK lets you email companies and other corporate bodies without consent, as long as you identify yourself and offer an opt-out, but treats sole traders as individuals. GDPR applies on top whenever you process a named person’s data, so record where each address came from and why you are writing.

Canada’s CASL requires consent, which can be implied when someone has published their business address without saying they don’t want messages and your email relates to their role. This is general information, not legal advice: check the rules for each country on your list before a campaign.

Cold emails for a job

The same rules work when you write to a hiring manager instead of a buyer. Pick a specific team and person rather than a generic careers address, open with what drew you to their work, name one or two accomplishments that match the role, and ask for something small, such as a 15-minute call or a pointer to the right person. Link to your portfolio or profile instead of attaching a large file, and follow up once after a week.

The art of writing good cold emails is hard to master. But with the help of marketing automation systems and a pinch of good will, we can make cold mailing very successful. The key is to pay attention to the real needs of prospects and to respond to them accurately.