How to Warm Up an Email Domain

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First, it’s essential to know that an email domain and an email address aren’t the same, but the warm up process for both has similarities.

Warming up your email domain takes longer than warming up your email address, especially if your domain is new.

Warming up a new domain is important because once it is burned, everyone else, like your coworkers who use your email domain in their email address, will be marked as spam.

In the following, you can find out how domain warming works and how you can do it.

What Is Email Domain Warming?

warming up a new domain infographic
Email domain warming is the manual or automatic process of sending emails from your email address in small volumes, gradually increasing the quantity, and receiving responses to increase the sender's reputation.

You have to start with a small number of emails where you expect your trusted recipients to open and reply to your emails. If you start sending a large number of emails, your email provider will flag your domain as spam.

And always make sure to work with our email deliverability checklist.

If your domain is new, create just one email address first and send a small number of emails manually.

Why Should I Warm Up My Email Before Sending Cold Emails?

Mailbox providers are wary of sending emails from domains with no history of sending or unfamiliar sending patterns.

To safeguard their clients from spam, mailbox providers typically block or filter large amounts of email from new domains, typically spamming.

How to Warm Up Email Domain

Before you send cold email sequences or campaigns, ensure your email domain is warm.
You can do this on your own or use a tool that takes over the work for you.

If you want to know how to do it on your own or how an email warm up tool works, read through the following steps:

Have at least two domains on hand

The reason for having at least two domains is that you don’t want to put your primary domain at risk. For example, is a primary domain that is related to our website.

Risking this domain by using it for cold outreach would be negligent. This is because once a domain's reputation is terrible, all email addresses from this domain will be flagged as spam.

To give our SDRs the best conditions to be successful in cold outreach, we set up a second domain. This one is called and is made for cold email outreach.

It is important that all of your domains are as similar as possible to each other. If you have two very different domains, your email domain might not be associated with your main domain by your recipients.

Avoid a - (dash) sign within your domain name in every outreach domain since this sign is related to phishing attempts and has a bad reputation.

Start with domain warm up

As a rule, a new domain is seen as highly suspicious in the first 30 days of existence by ESPs (Email Service Providers).

Spammers are known to burn a domain within the first 30 days. As a rule, spammers send out emails immediately in masses, and as soon as the reputation is bad, a new domain is simply acquired.

To be on the safe side here, wait for about three months with a new domain until you start with 100% of your outreach work.

Set up just one email account on your new domain

You can choose to add another email address to your domain after one to two months. It's critical to take your time. Maintain a gradual pace, and your domain will warm up without any problems.

Here spammers are known for having multiple email addresses per domain to send out as many spam emails as possible. That's why you should start slowly to show that you have organic traffic on your new domain.

Create authenticity

This is more a technical part which is crucial to the long-term success of sending cold emails.

A first step in the right direction is to ensure that SPF authentication methods are used. Sender Policy Framework (SPF) allows domain owners to specify a list of IP addresses and domains permitted to send emails on behalf of that domain.

Correct SPF configuration allows email recipients to trust that illegitimate messages will be sent to quarantine or reject status, thus allowing legitimate messages to be delivered as intended.

By including a signature in every outgoing email, DKIM (DomainKeys Identified Mail) works with SPF to confirm that the sender is responsible for the content. Prospects are more trusting when they see that your business digitally signs its emails, enhancing your company's reputation.

DMARC (Domain-based Message Authentication, Reporting, and Conformance) provides information about the message to recipients so that senders can understand what recipients see.

It allows you to view and decode the data sent from recipients to see what customers see when your company's emails are delivered to their inboxes.

The use of DMARC is a crucial part of improving sender reputation implementation. You can deter email abuse like spam, phishing, and spoofing the best if you use all three approaches: DMARC, SPF, and DKIM.

Send just a few but relevant emails

Sending only relevant emails can help you avoid accusations of spam. Before sending an email, ensure it is relevant to your recipient.

You can start by sending emails to your friends, close business contacts, or everyone who’s likely to open and reply to your emails.

Your goal is to have a high engagement rate. If your rates are high, your ESP recognizes this and will see you as more reliable.

Do this within the first 30 days but keep your daily email number between 5 to 15 emails.
After 30 days, you can also start with cold emailing. But don’t send too many emails a day. Your domain is still new, and getting a bad domain reputation is still likely to happen.

Make sure your email is relevant to your customer base and that it provides a solution to a genuine problem to make them interested.

This is particularly relevant when sending newsletters or cold emails, as these often fall foul of spam filters due to the content's large volume, frequency, and dubious relevancy.

But signing up for newsletters with your new domain is very good because there will be more traffic in your inbox.

In general, having traffic in your inbox is good and shows your ESP that you are not sending or spamming from your domain.

Do You Want To Do All the Work on Your Own?

Now that you know how to handle a new domain, the question is if you have the time and nerves to do it.

Alternatively, you can automize this step by using Warm.

A tool that is made specifically for salespeople from email deliverability experts to warm up their mailboxes and improve cold email deliverability.

We know that a high engagement rate is crucial to gaining email service providers' trust, and that’s what warm can achieve: a high engagement rate.

You can add your original copy from your cold email campaigns and sequences, and warm will ensure that your emails will be opened and replied to.

Before you start sending out your campaigns, you can be sure that Warm can establish trust with your ESP, and no more emails will be marked as spam.


To establish a sender reputation for a new domain or one that has not been sending emails frequently, you begin by sending emails from it in small volumes and gradually increasing their quantity as per a set schedule.

You have to start with a small number of emails where you expect your trusted recipients to open and reply to your emails.

If your domain is new, create just one email address first and send a small number of emails manually.

You can also use warm instead to warm up your email domain. Once warm has warmed up your domain, you can set up several email accounts to send cold emails.

If you’re interested in using Warm to warm up your domain, fill out this form, and we’ll be in touch soon.
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