Email warm up is an essential component behind the success of your cold emails. It represents a method of preparing an email address for future campaigns, helping it avoid the spam folder.

A good IP warming strategy is truly important, but particularly for bigger sales and marketing teams who use cold emailing extensively.

In this article, you'll learn:

What is IP warming or email warm up?

Email warm up (also known as IP warming) is a process that involves a gradual increase of your email sending volume. In order to build a good reputation, your email address needs to be warmed up. A warmed up address is one that has been sending and receiving messages regularly.

An email address can be at a different stage depending on how you've been using your account and how old your domain is.

How does the email warm up process look like? What's the best warm up schedule? How can you know when an email address has been properly warmed up? What to do if you have a new domain?

You're about to find out.

There are two ways in which you can warm up an email domain. You can do it automatically and manually.

In this article, we'll talk about both strategies.

Use an auto email warm up service like lemwarm

This is probably the best IP warming strategy. Why?

After a few weeks of leveraging it, you'll see open rates of 50%.

Then, once you switch to a long-term lemwarm strategy, you'll start hitting 80% open rates.

You'll discover how to make that happen for your email domain in a minute. First, lemme tell you one short but cool story.

The lemwarm idea started thanks to our users. One day in the lemlist community, Vaibhav opened a really important topic.

lemlist community

This is how lemwarm was born. We literally stopped what we were doing at the time, joined the conversation and decided to build one of the most important features for our community.

Btw, lemwarm is an email warm up service that allows you to send and receive emails from other lemlisters (our awesome users 😎).

It's all done on autopilot, without you lifting a finger.

How lemwarm works?

Since your account is connected to lemlist, we send emails to other lemlisters using your account with unique content. Each message and subject line is generated via our smart content algorithm. This is important because email providers will check and evaluate it.

On top of that, lemwarm email warmer will also create conversations by replying to those messages with more unique content and keeping them under the same thread.

The beauty about these conversations is that you'll be joining a mailbox network that consists of 20K+ people from 100+ countries.

Unlike some other tools that offer warm up service, lemwarm doesn't allow fake email addresses to join as they ruin our email domains. Instead, you'll be exchanging emails with real people, including those from companies like Zendesk, Meero, Malt, Adeco, SAP, Uber, and more.

This is what makes lemwarm probably the world's coolest email warm up software.

How do you start?

For your cold emails to stay out of spam, there are two things we need to do.

  1. Warm up your email address so you can start sending outreach campaigns (50%+ open rates strategy)
  2. Adjust your lemwarm so your cold emails stay out of spam forever (80%+ open rates strategy)

Btw, these are not some random numbers I'm giving you to charm you. These are actual results I saw thousands of our users achieve by consistently using lemwarm.

Here's how you can do it too...

Step 1 - Go to your lemwarm settings and see how old your email is.

ip warming strategy

lemwarm will tell you how old your email address is. This is important because it will dictate your warm-up strategy.

If it's younger than 6 months:

  • Number of warm-up emails per day: 30
  • Ramp-up increment value: 1

If it's older than 6 months:

  • Number of warm-up emails per day: 40
  • Ramp-up increment value: 2

During the initial warm-up phase, try not to send outreach campaigns at all. In case you want to, we strongly suggest keeping lower sending volumes.

  • 25-50 emails a day during week 1
  • 50-100 emails a day during week 2, etc.

Initial warm-up will last up between 3 and 4 weeks. Once completed, you should see your open rates hit 50%+ levels.

But, there's a way to go all the way to 80%.

Get ready for the magical tactic number two.

Step 2 - Keep your emails away from spam forever

After the initial warm-up phase, you can start sending campaigns. But the job isn't finished!

If you want to hit 80% open rates and never ever go to spam, this is a crucial step.

In your setup, leave the number of warm-up emails per day at 40 and keep lemwarm active.

Otherwise, your open rates will drop eventually. You'll see this in your reports as we've tested it with 1000s of our users. :)

Btw, as soon as you launch lemwarm, the automatic warm up of your domain begins immediately. If you're working in a bigger sales team, you can warm up all their email addresses at the same time.

Special feature πŸ”₯ - Β If a lemwarm email goes to spam by any chance, we'll bring it back into your inbox automatically. Yessir! ;)

Wanna start using lemwarm? Follow me here.

How to use lemwarm reports to check your progress?

At any point of time, you can see how many emails are reaching the primary tab versus how many are going to spam or promotion folders.

To access reports, open the dropdown menu in the upper left and click on reports (shortcut R). Then, in the left menu, click on lemwarm.

Here's the data you have at your disposal.

email warmup service

On top of that, you can also assess your weekly performance:

email warm up tool

How do I send my lemwarm emails to a specific folder in the inbox?

Go to your email account and set up rules. To be more precise, you want lemwarm emails to go to a specific folder and not drop in your primary tab. By doing so, you won't be mixing them with other emails.

email warm up

You should tick the following filters:

  • Always mark it as important
  • Skip the inbox (Archive it)
  • Never send to spam

This way, you're telling Google that these emails are important to you. Hence, they will never go to spam which makes it an even bigger sign to get the best domain reputation possible.

Is the lemwarm email warm up tool reliable?

It's the most reliable email warmup tool you'll find on the market. Just type "lemwarm reviews" on Google and see for yourself.

Here's why that's the case:

  • lemwarm's complex, proprietary algorithm which operates on 100+ different parameters
  • real people with verified emails and no fake accounts in the network
  • 20K+ users worldwide
  • 25+ years domain range
  • automatically pulls your warm up emails out of spam and promotions

When you combine all these factors, they define lemwarm's reliability. This is why big brands like Zendesk and Malt trust our ip warming service.


We'd be thrilled to have you join our amazing mailbox network.

Manually warm up the inbox yourself

The manual IP warm up strategy usually comes down to sending emails to your friends and acquaintances on your own, one by one.

That being said, you should also ask them to reply back. As previously stated, it's imperative for conversations to take place because email providers will be evaluating this kind of behavior.

Although warming up an ip address for email manually might take time, if you processize things, you'll be able to build a strong email address that's ready for cold email campaigns.

Let's address all the important questions you might have at this stage.

First, does IP warming email content matter to deliverability?

It's 2021 and email providers became even smarter throughout the last few years, so they will be keeping an eye on the quality of your emails.

If you decide to exchange one-word warm up emails, let's just say that you will be warming up your domain similar to an athlete who decides to warm up just their knees, and not ankles.

You don't have to come up with super smart content either. Some emails can be longer, others shorter. But make sure it's meaningful and looks like something people would actually exchange in their inboxes.

Our advice is also to prepare templates for your friends and acquaintances so that they can just copy/paste and reply fast. Remember, you are fighting friction and should make people's lives easier.

Set up your email account profile correctly

I never really understood why people create fake accounts. If you're not a spammer or a fraud, it doesn't make sense.

As a Serbian whose first name is not easy to pronounce, I understand if you have doubts about going for an international market feeling handicapped. But I look at that handicap as fuel. It's like an underdog team beating reigning champions.

The brand behind your company name plays a strong role and can help you down the road. Having just Vuk is one thing, but Vuk from lemlist has more firepower.

The same applies to personal brands. Vuk who posts incredible LinkedIn content about growth marketing is totally different than just Vuk.

To cut the long story short, don't jeopardize your email account with fake or incomplete info. Email providers won't like it and it will impact your email reputation in the long term.

Let's take Gmail as an example. You've created your address and you need to fill in the blanks.

Make sure to enter all the necessary information so it looks as complete as the example below. πŸ‘‡

Set up your email account profile correctly

Now you know when G's birthday is, so you can send him a cool gift when his day comes. πŸ˜‡

Example IP warm up schedule

Finally, let's see how your email warm up schedule could look if you decide to do it manually.

The numbers may vary depending on who you're emailing and what does your complaint rate look like.

Week 1

  • Start by sending 10 to 20 emails per day
  • In total, you should send between 70 and 140 emails in week 1

Week 2

  • We continue to crack on, but you raise the stakes to 20 to 40 emails a day
  • Total amount is 140-280 emails

Week 3

  • Now we move to 40-80 emails in a day

Week 4

  • Here you increase to 80-100 emails a day

Weeks 3 and 4 can be tricky to execute manually.

When it comes to replies and the amount you should receive, the answer is the more, the better.

At a minimum, you should aim to achieve a 25% reply rate ratio. Meaning, if you send 200 emails, you should get at least 50 replies.

Sending 500 emails and getting no replies is a problem.

When buying an email domain from someone is a bad idea?

Email domains can be bought and sold, just like in any marketplace. No problem with that. Unless you purchase one that comes with a bad reputation attached to it.

Let me tell you one story here. 🀯

One user of ours bought a new domain and started warming it up. In a few days, lemwarm showed that more than half of emails were going to spam.

The entire setup (e.g. DNS) was done correctly and the user didn't start to send outbound campaigns at that moment.

Confused by the situation, the user decided to come to our support to figure out what the hell is going on.

After chatting together, our team discovered that the user purchased that domain recently. But here's the catch.

That email domain has been bought and sold 27 times since 2011 and was used by spammers in the past. #ShitHappens πŸ’©

It's like buying a used car. You have to be really careful, otherwise, you might end up with a car that will stop in the middle of nowhere.

How to know domain history prior to making the decision to buy?

Easy! Use this tool.

Key takeaways

Always keep in mind the following:

  • Email warm up is an essential component because it influences your sending reputation and email deliverability big time
  • When looking for email warm up software tools, make sure they're using real accounts from people, have reliable algorithm and sending practices you can trust
  • If you're going to do manual IP warming, make sure to go through the list in this article to perfect your schedule and email content