IP Warming Best Practices

Improve your email deliverability and avoid getting marked as spam with these essential IP warming tips from Unfiltered.
Did you know that IP warming can be the deciding factor in the success of your email marketing campaign? Yet, it's often overlooked.

To ensure your emails reach the right audience and maintain a positive reputation with ISPs, understanding IP warming best practices is a must.

In this blog, we'll break down exactly what IP warming is, why it's crucial, and provide expert tips on how to warm up your IPs for optimal deliverability effectively.

So, grab your latte, and let's dive into the world of IP warming!

What is IP Warming?

IP warming is the process of gradually increasing the volume of emails you send from a new IP address to establish a positive reputation with internet service providers (ISPs).

ISPs monitor email traffic to prevent spam and malware, so when they see a sudden surge of emails coming from a new IP address, they may block or filter them out.

If you gradually increase your email volume and follow email best practices, you'll build trust with ISPs and improve your deliverability rates over time.

It's an important process to learn for any email marketer looking to reach their audience effectively.

Why Should You Warm Up Your IP?

Email service providers (ESPs) closely monitor new IP addresses to prevent spamming. If you warm up your IP, you demonstrate to ESPs that you are a credible sender with a valid email list that got consent.

Neglecting to warm up your IP can lead to issues such as poor email deliverability, increased spam complaints, and being placed on blacklists.

Gradually warming up your IP will establish a positive reputation with ESPs, and adhering to best practices will help maintain this reputation over the long term.

Types of IP Addresses

Dedicated IP Address

A dedicated IP address is an IP address dedicated to a single sender. Dedicated IPs provide more control over your email deliverability as it only influences your email sending.

You can build your sender reputation based on your emails' performance. However, dedicated IPs are usually more expensive than shared IPs.

Shared IP Address

A shared IP is used by multiple senders. While cheaper than a dedicated IP, you don't have as much control or ownership over the IP reputation.

The downside of shared IPs is that if one sender behaves poorly, it reflects badly on every sender using that IP address.

Check out our blog "Shared IP vs Dedicated IP Addresses" to learn more.

Which One Should You Choose?

Choosing a shared or dedicated IP depends on your email marketing needs. If you send out large volumes of transactional emails and have a high-level email authentication set up, you can consider using a dedicated IP.

A dedicated IP is suitable for companies with a well-established IP strategy, compliance plan, and budget.

However, if you have a relatively small list or are on a limited budget, it's best to go for a shared IP.

Shared IP environments are ideal for sending low-volume newsletters, marketing emails, and lifecycle messages.

IP Warming Tips

ip warming tips

Start Small

Begin by sending a small volume of emails to your most engaged subscribers.

Expand the recipient list to include less active subscribers as you gradually increase email traffic.

By starting small, you can monitor the deliverability metrics and adjust accordingly to avoid emails being marked as spam or having a high bounce rate. This will also help you to establish a better sender reputation score, which is critical for successful email delivery.

Have Engaging Email Body

The second tip for successful IP warming is to have an engaging email body.

The more your subscribers engage with your emails, the better their engagement score will become, which will ultimately positively affect your email deliverability score.

Make sure your emails are visually appealing and have clear calls-to-action to encourage engagement and avoid having your email flagged as spam.

Set a Consistent Sending Schedule

The third tip for successful IP warming is to set a consistent sending schedule.

This means that you should send emails at a consistent frequency, time and day.

This will help train the email service provider algorithms to expect and trust your emails, leading to better deliverability rates.

Monitor Deliverability Metrics

The fourth tip for successful IP warming is to monitor deliverability metrics, which include bounce rates, spam reports, and sender reputation scores.

Bounce rates and spam reports indicate how well emails are being delivered to subscribers and whether they are landing in their inbox or spam folder.

Sender reputation scores are calculated based on the engagement of your subscribers and the quality of the emails you send. Monitor these metrics and adjust your IP warming strategy to improve your score.
Bounce Rates
Bounce rates happen when your emails are rejected by a recipient's email server and are returned to the sender's inbox.

Higher bounce rates can damage your sender reputation and negatively impact email deliverability, and even lead to your email addresses getting blacklisted.

Monitor your email bounce rates closely to quickly identify any issues with your email list quality or sender authentication, allowing you to take corrective action immediately.
Spam Reports
Spam reports are when a recipient marks your email as spam, which can have a significant impact on your sender reputation and deliverability.

To minimize the risk of high spam reports, it is essential to follow best practices for email marketing, like sending relevant and valuable content to your subscribers.

It would help if you also had a clear and easy-to-understand unsubscribe process to ensure that your subscribers have the opportunity to opt-out easily.
Sender Reputation Scores
Your sender score is calculated by monitoring several factors, including engagement rates, spam complaints, and bounce rates.

A low sender reputation score can negatively impact your email deliverability, so it would help if you aimed to maintain a high score by following best practices like sending personalized and relevant emails to your subscribers.

Clean Your Email Lists

The fifth and final tip for successful IP warming is to clean your email lists.

Remove inactive subscribers and those who haven't engaged with your emails in a while.

This will help to improve your engagement score and overall reputation. Send emails to a clean and engaged list to have a higher chance of increased deliverability.
Improve your email deliverability with Unfiltered.ai

Warm-Up Your IP Automatically with Unfiltered.ai

The key to a successful email campaign is warming up your IP address. Email service providers and spam filters monitor IP address behavior closely.

With an optimized IP address and good sender reputation, your emails are more likely to reach recipients and not end up in their spam folders.

You can achieve that with Unfiltered.

Start by creating an account with a free trial, then set up your DNS settings and the emails you want to warm up, and it’s done! Your email warm-up campaign will start automatically, and you don’t need to do anything else.

You can see the progress of the email warm-up campaign, and your email health in the dashboard.

By following this process, you'll adapt to ISP policies and minimize the risk of triggering spam filters. Increase the chances of your emails reaching recipients' inboxes by demonstrating responsible sending behavior with Unfiltered.


Before sending out emails, it’s important to gradually warm up your IP address to build a long-lasting positive reputation with mailbox providers. Warmed-up IPs indicate that your emails are genuine, that you have a good list, and that you send appropriate messages.

Choosing between a dedicated or a shared IP address depends on your email marketing needs. Finally, to warm up an IP safely and effectively, you should follow the best practices by gradually increasing your email volume, monitoring your sending metrics, and setting up your email authentication keys.

Start the process early, maintain a healthy email list, and your subscribers will appreciate the quality and legitimacy of your emails.

Start a free trial, and warm-up your email with Unfiltered today!
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