Most cold email never gets a chance to be good or bad: it goes to spam, or bounces. Before you worry about the subject line, get the plumbing right. This is the checklist we run for every BeatTheDoor client.
1. Authenticate the sending domain
- SPF: one TXT record listing the services allowed to send for your domain. Two SPF records is a common mistake and makes receivers ignore both.
- DKIM: your email provider signs each message; you publish its public key in DNS. Microsoft 365 and Google Workspace both have a switch for it.
- DMARC: a TXT record at
_dmarc.yourdomain.com. Start withp=noneto watch, move toquarantineonce you're sure all your mail is signed.
Since 2024, Gmail and Yahoo require every sender to authenticate (SPF or DKIM) and keep spam complaints low, and senders of large volumes to have SPF, DKIM, DMARC and one-click unsubscribe. Small senders aren't exempt from the basics.
2. Consider a sister domain
If your main domain carries invoices and customer support, protect it: send outreach from a close variant
(get-yourcompany.com) that redirects to your site, with its own mailbox and authentication.
3. Warm up, then stay small
A brand-new mailbox that sends 200 emails on day one looks like a spammer, because that's what spammers do. Ramp up over a few weeks; we use 10 a day in week one, 20 in week two and 30 in week three. After that, keep each mailbox to a few dozen cold emails a day and add mailboxes for more volume, rather than pushing one harder.
4. Check every address before you send
Bounces tell mailbox providers your list is bad. Before anything goes out:
- Make sure the domain has a mail server at all.
- Ask the mail server whether the mailbox exists, without sending anything. Some servers accept every address ("catch-all"), so treat those as unconfirmed.
- Drop role addresses that bounce or belong to someone else, like a filing agent's address on a registry record.
- Never email anyone who has opted out, from any of your campaigns.
5. Write like a person
- Short: four or five lines. Say who you are, the specific thing you noticed, and one easy next step.
- Specific beats clever: "I couldn't find a website for Northside Roofing" works because it's true and only true for them.
- Plain text or close to it. No images, attachments or link shorteners in a first email.
- One ask. "Worth a 15-minute look?" is easier to answer than a calendar link and a brochure.
6. Follow up, briefly, and stop when they answer
Most replies come after the second or third email. Two follow-ups a few days apart, in the same thread, is plenty. The moment someone replies, bounces, or asks you to stop, the sequence ends. An automatic "following up" after a real reply is the fastest way to lose a prospect.
7. Follow the law (it's not hard)
In the US, business email outreach is governed by the CAN-SPAM Act. Every email must:
- use honest From, To and subject lines;
- say it's an advertisement or offer;
- include a valid postal address;
- tell people how to opt out, and you must honor it within 10 business days (do it the same day).
Penalties run to tens of thousands of dollars per email, so this isn't optional. Other countries are stricter: Canada's CASL and the EU's rules generally need consent first, so this checklist is for US B2B outreach.
8. Watch the numbers
Track bounces, replies, unsubscribes and spam complaints per mailbox. Rising bounces mean the list needs checking; complaints mean the message or the targeting is wrong. Pause a mailbox before its reputation does it for you.
BeatTheDoor sets all of this up for you on your own domain, checks every address before it's emailed, warms each mailbox up and stops a thread the moment someone answers. You approve the emails; we handle the plumbing.