A Step-by-Step Domain Warm-Up Guide

BySuryanarayan Pal


Linkedin logo
Twitter logo
copy link
Facebook logo
Whatsapp logo
Pinterest logo
mail logo

Have you ever wondered why sending thousands of emails with a new domain gets your email address blocked or has a very low delivery rate? A crucial step in saving your emails from getting flagged as spam is to warm up your domain for mass emailing. This guide will discuss the step-by-step process one needs to follow to warm up domains.

Table of contents

What is a domain warm-up?

Warm-up is like building a good credit score by piggybacking on good transactions. Since most of the spam filters like Gmail, Yahoo, Apple, Outlook & Hotmail work on machine learning algorithms, it's imperative to generate the best open rates and send emails in controlled volumes, to build a good score with the spam filters.

In 2019, Google took more stringent steps from email sending and receiving sides to detect spam emails. The email service provider gives daily sending limits when a user opens a new email account. However, a new account can't use it entirely. Ideally, it takes 8-12 weeks to accomplish maximum deliverability.

The warming-up process may seem sluggish and repetitive, but it is essential when you want to escape the dreaded spam folder.

Why do you need to warm up your domain?

Email domain warm-up signals your service provider that you are not a robot or scammer. Preparing a high-volume cold email campaign from a new account is crucial.

Below are the most important reasons you should not overlook the domain warm-up process.

• Avoid spam folder

Every domain acquires a reputation that ranges from bad to good. And, the host considers a new account suspicious from the outset. Hence email warm-up service is needed to ensure that emails reach the receivers' inboxes and build a good domain reputation.

• Email throttling

Email throttling implies controlling the number of emails sent to one ISP or remote server at one time. So, when many emails are sent at once without domain warm-up, the receiving ISPs often block these messages because they seem spam. Read how SBNRI reduced their spam rate with Mailmodo, leading to a 16% increase in open rates.

• Grey-listing

As per SMTP, a grey list is a list of email addresses or domain names used by a spam filter to detect suspicious emails. If a message comes from the list's address or domain, it will temporarily be blocked. So, you must warm up your domain to steer clear of grey-listing.

In a nutcase, domain warm-up will increase your deliverability and open rates while decreasing your bounce rates.

Related guide: How to Avoid Email Blacklisting

A step-by-step guide to email domain warm-up

Domain warm-up demands your time and efforts, as it is a long-term commitment. You might want to use your existing company domain to send emails. As it already has a good reputation, it reduces the energy needed for warming it up.

Unfortunately, you might encounter problems and burn your primary domain of everyday business. So, please register a new domain and prepare it for email outreach.

Following are the basic checks to ensure that the warm-up builds a good reputation with spam filters:

Get this pre-send checklist to hit send with confidence

An interactive checklist to send error-free emails

1. Choose the best data set

The strategy is the key to warming up a new domain name. Ensure that the best data set is being targeted at the time of warm-up. The best data set, i.e., users who would have the maximum probability to open emails, would vary from industry to industry.

In the e-commerce industry, users who have opened and clicked the previous emails would have the maximum probability, whereas, in the job industry, users who have recently signed up would have the maximum probability. Hence it's essential to understand the business and identify users who would generate maximum opens and not target users who may open and report to spam or not open at all.

Marrying platform activity with email activity and identifying different cohorts like email active & platform active, email active & platform inactive, email inactive & platform inactive, and email inactive & platform inactive is the key.

Also, an alternative hack is to introduce triggers like transaction confirmation, OTP & forgot password emails on the new domain name for 5-7 days. This helps build the domain's reputation, and you can start the promotional email warm-up from where you have left off!

For example, if your daily transactional email volume is 2K/day when you start the promotional emails, you can start with a volume of 2K/day!

2. Choose a healthy infrastructure

Ensure that you assign pre-warmed IPs and have a high reputation with Gmail/Hotmail. If it's a shared IP pool, ensure that you clean up other brands with poor deliverability.

Also, ensure that the IPs don't have a reputation for hitting spam traps, and also the database is also used to warm-up is clean from spam traps. Spam traps in the database are a negative element and an indication of poor management of data. Lastly, ensure that the domain name used to send emails is at least 30 days old.

3. Choose your content wisely

Ensure that the email content isn't bland and personalized enough to entice the users to open it. Also, avoid sales-y content in the early phase if you kick-start your email program-send blog based content that users are interested in reading.

For example, If you are in the travel industry, you can send topical blog-based content like places to travel in India in the monsoon instead of sending offers.

If you already have had a history of sending EDMs, ensure that you aren't sending any content which has a prior reputation of landing in spam. It would be best to avoid alt, title & map tags in the content. Alt & Title tags have keywords that easily get cached by Gmail and other ISPs.

4. Authenticate your email

Account authentication is the first thing required with a new email address. After registering a single domain name for email outreach, follow these steps:

Related guide: The Beginner’s Guide to Google Postmaster in 2022

5. Build a definite warm-up schedule

To achieve full email deliverability, generate engagement in your warm-up emails. It is vital to have daily conversations as it is a continuous 8-12 week operation. Having a faithful response base gives the ISP a hint about your legitimacy. Sending the emails at a fixed time and not sending more than 1.5X the previous day's volume. Also, you shouldn't send the same content for more than 4-5 days.

This is what a typical warm-up plan looks like assuming we are looking at a scale of 300K/day.

How can Mailmodo help with your domain warm-up?

Mailmodo provides you with dedicated service from the moment you sign up. In addition, we do regular follow-ups of our clients regarding any issue they might face.

How can we offer you the right email warm-up service?

  • Mailmodo is an email marketing platform with proven deliverability. Our clients celebrate an increase in over 225% conversion rates by using interactive AMP emails.

  • Using Mailmodo's email marketing software, you can send bulk and triggered emails helping you to automate the warm-up process.

  • Mailmodo provides a dedicated account manager for enterprise clients to warm up the email domain. Our experts will back you up with any queries regarding the process.

  • Mailmodo's integrated trackers help you monitor your emails' output and export full reports of user activities & campaign results.

Get a sample AMP email in your inbox

Experience the power of interactivity right now


The strictness of the algorithm is to maintain a grip on junk emails. As a genuine user, help the system realize that you are not a spammer by following the practices mentioned above. While you are learning and becoming a pro, Mailmodo is here to provide a one-stop solution to warm up your domain and send interactive emails that help you get more conversions.

What you should do next

Hey there, thanks for reading till the end. Here are 3 ways we can help you grow your business:

  1. Talk to an email expert. Need someone to take your email marketing to the next level? Mailmodo’s experts are here for you. Schedule a 30-minute email consultation. Don’t worry, it’s on the house. Book a meet here.

  2. Send emails that bring higher conversions. Mailmodo is an ESP that helps you to create and send app-like interactive emails with forms, carts, calendars, games, and other widgets for higher conversions. Get started for free.

  3. Get smarter with our email resources. Explore all our knowledge base here and learn about email marketing, marketing strategies, best practices, growth hacks, case studies, templates, and more. Access guides here.

What should you do next?

Thanks for reading till the end. Here are 3 ways we can help you grow your business:


Get smarter with our email resources

Explore our email marketing guides, ebooks and other resources to master email marketing.


Do better email marketing with Mailmodo

Send app-like interactive emails with forms, carts, calendars, games, etc. to boost email ROI.


Talk to an email expert

Get a 30-min. free email consultation with a Mailmodo expert to optimize your email marketing.

Was this post useful?

Get 3X conversions
with interactive emails


Create & send interactive emails without coding


Put revenue on auto-pilot with pre-built journeys


Save time with AI-powered email content creation

1000+ businesses grew with Mailmodo, including