Guide
Cold Email: The Complete Guide
A cold email is a first message to someone you haven't spoken to before. Here's how to write one, the subject lines and follow-ups that get replies, and the setup that keeps you out of spam.
Subject quick question about Northwind's outbound
Hi Jordan,
Saw Northwind just opened two SDR roles. Teams scaling outbound usually hit the same wall: new domains landing in spam.
We help teams like yours set up pre-warmed mailboxes in minutes, so new reps can send from day one.
Worth a 10-minute chat next week?
Sam
Meaning
What is cold email?
Cold email is one-to-one outreach to a person who doesn't know you yet, with a specific reason for writing to them. Done right it's how many B2B companies book their first meetings. Done wrong it's spam.
| Cold email | Spam | |
|---|---|---|
| Who gets it | A specific person picked for a reason | Everyone on a bought list |
| Why them | A relevant, personal reason to write | No reason at all |
| Sender | A real person on a real, authenticated domain | Spoofed or anonymous |
| Opting out | Easy, and honored immediately | Ignored |
| Volume | About 30 a day per mailbox | Thousands from one account |
Writing
How to write a cold email
Every good cold email has the same five parts. If a sentence doesn't serve one of them, cut it.
Step 1
Subject line
Short, lowercase, reads like an email from a colleague.
Step 2
Opening
Why them, why now: a trigger, a role, a shared context.
Step 3
Value
One problem you solve, in their words, not yours.
Step 4
Proof
One line: a similar customer or a concrete result.
Step 5
One ask
A yes/no question. No calendar link in the first email.
Cold email template
First email
Subject: {{trigger}} at {{company}}
Hi {{first_name}},
Noticed {{company}} {{trigger — e.g. just opened 3 sales roles}}.
Teams at that stage usually {{the problem you solve}}.
We help {{similar companies}} {{outcome}} — {{customer}} {{result}}.
Worth a quick chat next week?
{{your_name}}Keep the first email plain
Subject lines
Cold email subject lines that get opened
| Pattern | Example | Why it works |
|---|---|---|
| Question about them | quick question about {{company}}'s hiring | Personal and specific; reads like a real email. |
| Trigger event | congrats on the series A | Proves you did your homework. |
| Mutual connection | {{name}} suggested I reach out | Borrowed trust. Only use it if it's true. |
| Their goal | {{goal}} in Q3? | Leads with their priority, not your product. |
| Two to three words | {{company}} + {{your company}} | Short subjects survive mobile truncation. |
| Follow-up | re: {{previous subject}} | Keeps the thread together. Never fake a “re:”. |
Avoid ALL CAPS, exclamation marks, “free”, “guarantee” and fake urgency. They hurt open rates and deliverability.
Follow-ups
How to follow up on a cold email
Many replies come from follow-ups, not the first email. Space them out and make each one add something new.
Step 1
Day 0
First email: the reason, the value, one question.
Step 2
Day 3
Short bump in the same thread with a new detail.
Step 3
Day 7
Different angle: a case study, a resource or a smaller ask.
Step 4
Day 14
Polite close: “Should I stop reaching out?”
Follow-up 1 (day 3)
Hi {{first_name}}, floating this up in case it got buried.
One more detail: {{customer}} cut {{metric}} by {{result}} in the first month.
Worth a look?Follow-up 3 (day 14)
Hi {{first_name}}, I haven't heard back, so I'll assume {{problem}} isn't a priority right now.
Should I close the loop, or is there someone better to talk to?Infrastructure
How many mailboxes you need for cold email
Volume per mailbox is the number that keeps you out of spam. At about 30 emails per mailbox per day over 22 sending days a month, here's what each volume takes.
Mailboxes needed by monthly cold email volume
30 sends per mailbox per day, 22 sending days per month.
| 5K emails / month | 8 |
|---|---|
| 15K emails / month | 23 |
| 30K emails / month | 46 |
| 60K emails / month | 91 |
| 100K emails / month | 152 |
| Emails per month | Emails per day | Mailboxes | Domains |
|---|---|---|---|
| 5,000 | 227 | 8 | 3 |
| 15,000 | 682 | 23 | 8 |
| 30,000 | 1,364 | 46 | 16 |
| 60,000 | 2,727 | 91 | 31 |
| 100,000 | 4,545 | 152 | 51 |
Domains assume 3 mailboxes per domain. Plug in your own numbers with the mailbox calculator, or get them set up in minutes with Google Workspace business email.
Cold email best practices
- Send from separate domains so your main company domain is never at risk.
- Authenticate every domain with SPF, DKIM and DMARC. Check yours free.
- Warm up new mailboxes, or start with pre-warmed ones.
- Verify every address before you send; bounces hurt reputation fast.
- Measure replies and meetings, not opens. Open tracking is unreliable and adds a tracking pixel.
Get a cold email setup plan
Tell us where to send it. We'll reply with mailbox, domain and DNS recommendations for your sending volume — or start right away and have mailboxes live in minutes.
Where should we send it?
Or see pricing →Frequently asked questions
What does cold email mean?
A cold email is a first, unsolicited email to someone you have no prior relationship with, usually to start a business conversation: a sale, a partnership, a job or an introduction. “Cold” just means they don't know you yet.
Is cold emailing legal?
In the US, B2B cold email is legal under CAN-SPAM if your headers are accurate, the subject line isn't deceptive, you include a physical postal address and you honor opt-out requests within 10 business days. The EU, UK and Canada have stricter consent rules, so check local law before emailing people there.
How long should a cold email be?
Short enough to read on a phone without scrolling, roughly 50–125 words. One reason you're writing, one piece of value, one question.
How many follow-up emails should I send?
Two to three follow-ups spaced a few days apart is the norm. Each should add something new, such as a resource, a different angle or a simpler ask. Stop as soon as someone replies or asks you to.
What is the best time to send a cold email?
Weekday mornings in the recipient's time zone are a common default, but results vary by audience. Pick a window, test it against another for a few weeks and keep the winner.
Does cold email still work?
Yes, when it's targeted and technically sound. Most cold email that “doesn't work” never reached the inbox. Get authentication, domains and volume per mailbox right first, then optimize copy.