How to Warm Up a New Domain for Cold Email
· 4 min read
A brand-new domain that suddenly sends hundreds of emails looks like what it is: a new sender nobody has heard of. Mail providers watch for exactly that. The fix is not a trick. It is to set the domain up properly and then earn a reputation slowly, by sending a small number of good messages that people do not complain about.
Why a separate sending domain can help
If you send cold email from your main business domain and something goes wrong, your normal mail (invoices, replies to customers) suffers too. Many senders therefore use a separate domain for outreach, close to their own name, so that a problem stays contained.
Two rules about that:
- It must be honestly yours: the website on it, the names in the footer and the postal address all say who you are. Do not use a name that pretends to be someone else.
- It is more to look after: three mailboxes on three domains is three reputations to watch.
Set it up before you send anything
Three records in the domain's DNS tell receiving servers that your mail is really from you.
| Record | What it does |
|---|---|
| SPF | Lists the servers allowed to send mail for the domain |
| DKIM | Signs each message so the receiver can check it was not changed |
| DMARC | Tells receivers what to do with mail that fails SPF and DKIM, and where to send reports |
Your mailbox provider (Google Workspace, Microsoft 365, Zoho, your host) gives you the exact values and a page to check them. Start DMARC in monitoring mode, read the reports for a few weeks, then tighten it.
Also: a working website on the domain, a way to reach you, and a reverse DNS and TLS setup if you run your own server. If you use a normal mailbox provider these are done for you.
Ramp slowly
There is no official number. Providers do not publish one, and the right pace depends on how good your list is. As a starting plan, not a rule:
- Week 1. A handful of messages a day, to people who are likely to reply. Reply to every answer.
- Weeks 2 to 3. Raise the volume a little each day, and only if the last days were clean.
- After that. Add more only while replies keep coming and bounces stay low.
Mailbox providers also set their own ceilings. A free Gmail address stops at about 500 messages a day and Google Workspace at about 2,000, counted over 24 hours, and an account that suddenly sends hundreds of cold emails can be limited or suspended. A good outreach pace is far below those ceilings.
Keep the list clean
Reputation is lost fastest through bounces and complaints.
- Send only to addresses the business published. Check each address first.
- Keep the bounce rate under about 2%. If it goes higher, stop and find out why before you send more.
- Keep spam complaints very low. Google and Yahoo's 2024 rules for large senders ask for complaint rates well under 0.3%, and under 0.1% is the safer target. A small sender gains from the same habits.
- Honor every opt-out at once: how to handle STOP replies.
Write like a person
- Plain text, short, one link at most, no images, no tracking pixels.
- A real name in the From field and a real postal address in the footer.
- No words that read like an advertisement: "free", "guaranteed", "act now".
- A different sentence for each business. Identical text to hundreds of people is easy to detect.
Signs to stop and look
- Bounces over about 2% in a day.
- Replies that say "who are you?" or "how did you get my address?"
- Mail going to the spam folder in a test with your own other mailbox.
- A warning or a limit from your mailbox provider.
If any of these shows up, pause. Fix the list or the wording first. A pause costs a day; a blocked domain costs weeks.
Where AyePin fits
AyePin sends email one message at a time, inside hourly and daily caps and quiet hours in the recipient's own time zone, with a random gap between messages. It reads the mail server's bounce notices, never writes again to an address that does not exist, and pauses sending by itself when too many messages come back. It does not set up your DNS for you: SPF, DKIM and DMARC are done with your domain provider.
Once the domain is ready, the first messages matter most: a cold email template for local business owners.