Founders and sales teams use cold email to reach buyers who do not know them yet. It works when the message is relevant to the one person who gets it, and it backfires when it is sent in bulk. This guide covers what it is, where the line with spam sits, what the law asks and how to measure it.
What does cold email mean?
Cold email means writing to someone who has no relationship with you and has not asked to hear from you. The word cold comes from cold calling: there is no earlier contact, no subscription and no purchase. In B2B sales the goal of the first email is a reply from the right person, not a sale or a click.
Recruiters and partnership managers send cold email too, but this article is about the sales use: one company writing to a decision-maker at another company about a problem it can solve.
Is cold email the same as spam?
Cold email and spam overlap more than most sales guides admit. Spamhaus, which maintains email blocklists, defines spam as unsolicited bulk email, and in June 2025 it wrote that by that definition there is no difference between cold email and spam. Anyone sending cold email has to work with that view in mind.
In that definition, unsolicited means the recipient has not given verifiable permission, and bulk means one of a larger batch with substantively identical content. A cold email is unsolicited by nature, so the sender only controls the bulk part: a template sent unchanged to thousands of strangers is exactly what the definition describes. Spamhaus does not accept personalization as a way out either; its post says it is often used to sidestep anti-spam rules.
Mailbox providers measure the same thing from the other side. Google asks everyone who sends to Gmail accounts to keep the spam rate reported in Postmaster Tools below 0.3% and to aim for under 0.1%, according to its email sender guidelines. Yahoo's sender requirements set the same 0.3% ceiling. Each recipient who marks a message as spam pushes that number up, so writing to the wrong people also costs you the inbox of the right ones.
How is cold email different from marketing email and newsletters?
Cold email goes to people who have no relationship with you, while marketing email and newsletters go to people who subscribed or bought from you. The legal label can still be the same. The US Federal Trade Commission treats any email whose primary purpose is to advertise or promote a product or service as commercial, cold or not.
| Type | Who receives it | What it is for |
|---|---|---|
| Cold email | People with no prior relationship who did not ask for it | Starting a conversation with a likely buyer; success is a reply |
| Marketing email or newsletter | Subscribers who opted in, or existing customers | Promoting offers or content to an audience that already knows you |
| Transactional or relationship email | Customers in a transaction already agreed | Confirming or updating that transaction, which the FTC treats separately from commercial email |
The difference changes how you write. A newsletter can assume the reader knows your brand. A cold email has to explain in two or three lines who you are and why you are writing to this person.
What does a good B2B cold email contain?
A good B2B cold email contains a reason to write to this specific person, one observation that proves you looked, the problem you solve in their terms, a single small ask and an honest signature with a way to opt out. It fits on a phone screen and reads like one person writing to another.
- A subject line that says what the email is about. In the US it has to reflect the content, and the guide to cold email subject lines covers patterns and what to avoid.
- An opening about them, not you: something true and recent, such as a new office, a job opening or a product launch.
- The problem you solve, said the way the reader would say it, in one or two sentences.
- One ask that is easy to answer, such as whether a short call makes sense.
- Your real name, company and postal address, plus a plain line on how to stop further emails.
A cold email example, annotated
The cold email example below was written for this article, to a fictional company. It was not sent to anyone and has no measured result behind it. It shows the five parts of a good B2B cold email in under a hundred words: an honest subject, a specific opening, the problem, one question and a signature with an opt-out line.
- Subject: the new Austin team
- Hi Maria, I saw that Fieldline is hiring two account executives for its new Austin office.
- New teams in a new region usually start from an empty pipeline. We book first sales calls with operations leaders in a new market, so new hires start with conversations on their calendar.
- Would a short call next week make sense, to see whether that fits your plans for Austin?
- Sam Ortiz, Ridgeway Partners, followed by the company's postal address. If you would rather not hear from me, reply "no" and I will not write again.
| Part | What it does |
|---|---|
| Subject | Names what the email is about, so the open is honest |
| Opening | Uses a public fact about this company, which proves the sender looked |
| Problem | Describes the buyer's situation in one sentence instead of listing features |
| Ask | A yes or no question that costs little to answer |
| Signature | Real name, company, postal address and a plain way to opt out |
What has to be in place before the first send?
Four things have to be ready before the first cold email goes out: a written reason why each person should hear from you, addresses verified before sending, sender authentication on the sending domain, and an opt-out that works across every tool you use. Good copy cannot make up for any of them.
- A reason for each person. If you cannot say why someone should hear from you, do not write to them.
- Verified addresses. Check every address before the first send and remove the ones that fail.
- Authentication. Gmail and Yahoo require SPF or DKIM from every sender, and SPF, DKIM and DMARC from bulk senders. Yahoo also asks bulk senders to honor unsubscribes within 2 days.
- An opt-out that works everywhere. A request recorded in one tool has to stop every sequence in every other tool too.
Automating any of this adds more controls, such as shared suppression lists, stop rules and human approval. They are covered in what to control before automating cold email.
What do anti-spam laws require for cold email?
Anti-spam rules for cold email depend on the countries involved, and they do not agree with each other. In the US, the FTC says CAN-SPAM covers business-to-business email and sets content and opt-out rules. Spain and New Zealand start from the recipient's consent. None of this replaces advice from a lawyer for your case.
- United States. The FTC's CAN-SPAM compliance guide says the law makes no exception for business-to-business email. A commercial message must not use false or misleading header information or a deceptive subject line, must identify itself as an ad, must include a valid physical postal address and must explain how to opt out. Opt-outs must be honored within 10 business days, and the guide lists penalties of up to $53,088 for each email in violation.
- Spain. Article 21 of the LSSI prohibits promotional email that the recipient did not request or expressly authorize, with a limited exception for a prior contractual relationship and similar products or services. That the recipient is a company does not create a general permission.
- New Zealand. The Department of Internal Affairs says commercial messages may only be sent with express, inferred or deemed consent, must identify the sender and must include a working unsubscribe facility, with requests honored within five working days. Deemed consent only covers an address published conspicuously in a business capacity, for messages related to that role.
For other markets, read each country's official guidance. This is a summary of official sources, not legal advice, and it does not mean cold email is allowed in any of these countries. Ask a lawyer to review your data sources, message and opt-out process before the first send.
How do you measure cold email?
Measure cold email by what people do after they read it: replies, positive replies, meetings held, opt-outs and complaints. Open rates are a weak signal. Apple says its Mail Privacy Protection downloads remote content in the background whether or not the person engages with the email, so an open may only mean a machine loaded it.
- Delivered messages and bounces, split by list source.
- Replies, split into positive, negative and automatic.
- Meetings booked and meetings held. A booked meeting nobody attends is not a result.
- Opt-outs and spam complaints, watched every week in Google Postmaster Tools and your own tools.
Compare campaigns on the same denominator, such as positive replies per hundred delivered emails. Treat published reply-rate averages with care: most come from tool vendors' own customer data, which you cannot check.
When does cold email fit, and when does it not?
Cold email fits when you sell to businesses, can describe your buyer in two sentences and one new client is worth a real sales conversation. It fits badly when you sell to consumers, when the price does not justify a call, or when you need meetings this week, because list building and mailbox warm-up take time first.
- Good fit: B2B services, software, consulting and specialist suppliers whose sale starts with a call.
- Poor fit: consumer products, impulse purchases and offers you cannot yet explain in one sentence.
If you would rather not run this in-house, a cold email agency can handle the list, the writing, the sending setup and the replies. Ace Digital is one option: our booked meetings service writes to each company one by one and passes you only the replies that want to talk.
Frequently asked questions
Is cold email legal?
It depends on the countries involved and on how you send. In the US, the FTC's guidance sets content and opt-out rules for commercial email, B2B included. Spain's LSSI and New Zealand's spam law start from the recipient's consent. Ask a lawyer who knows your markets to review your case before you send anything.
How many follow-ups should a cold email sequence have?
Keep the sequence short: a first email and one or two follow-ups is plenty. Each follow-up should add something new, such as a different angle or a useful detail, not just ask whether they saw the last one. Stop the sequence the moment someone replies, opts out or asks you to stop.
Should I send cold email from my main domain?
A separate domain is a common precaution, so that complaints or a setup mistake cannot affect the domain your invoices, support and team email depend on. The separate domain still needs SPF, DKIM and DMARC, an honest sender name and a working opt-out. It does not make an irrelevant message acceptable.
What is a good reply rate for cold email?
There is no independent public benchmark you can rely on. The averages that circulate mostly come from tool vendors' own customers, with lists, offers and markets that are not yours. Set your own baseline from the first few hundred delivered emails and judge every change against it, counting meetings held as well as replies.