Key Points
IP warming gradually builds an email sender’s reputation, ensuring successful email deliverability.
Starting with a high volume of emails on a new IP can trigger spam filters, reducing email deliverability.
The IP warm-up process can take days or weeks, depending on your email volume and engagement.
Introduction
IP warming helps organizations improve their email deliverability, especially organizations with cold IPs. A cold IP is another term for a new IP. For example, a new email address is cold because you haven’t sent any email with it. When you begin your email campaign, you may be tempted to start sending emails in bulk, especially when you have a large list of recipients. However, it can quickly become counterproductive because ISPs and ESPs (Gmail and Yahoo) may categorize your IP as spam.
Why Warming an IP Matters
Warming IP matters for various reasons:
It improves your IP reputation: Solid reputations prevent your email from going to spam.
It ensures email deliverability: When you warm up, ESPs trust you and will deliver your messages to your recipients’ Inboxes – without any hassle.
Enhances audience participation: One strategy of IP warming is to ensure that a small number of recipients respond to your email. During the process, you will gain practical knowledge of what works and what doesn’t.
Sending large volumes of email from a new IP without first building a reputation can lead email providers to mark your emails as spam. Email Service Providers (ESPs) are naturally cautious with new or unknown senders—if they suddenly see thousands of emails coming from an unfamiliar IP, they may restrict or block them.
Think of IP warming as gradually introducing yourself to these providers. By slowly increasing the number of emails you send over time, you give providers a chance to see how recipients respond—whether they open, click, or engage with your emails. This gradual approach helps build trust with major providers like Gmail, Yahoo, and Outlook, ensuring your emails land in inboxes, not in spam.
How IP Warming Works
IP warming is quite simple: The aim is to warm up to email providers and ISPs. Let’s have a breakdown:
Send a few emails to the most active recipients in your email list. “Small” is relative and depends on your list; however, we recommend sending to no more than 500 recipients.
Ensure that the list engages with your email. You can also send emails to self-generated or self-created lists. Another trick is to ask friends for their email addresses. Many people have more than 5 emails. A 30–40% engagement over a week is an excellent start.
Gradually increase the list size.
Have a consistent sending rhythm. Sending emails too frequently is spammy. Also, prevent spam email, as they will hurt your email delivery.
Remember that different ESPs have different rules. For example, Gmail can be strict, so be careful.
If your engagement metric is positive, you can double your email volume. If engagement drops, reduce the volume.
Case Study 1
Let’s consider an e-commerce company launching its holiday campaign: Company X recognized their revenue growth and decided to transition from a shared IP to a dedicated IP – companies often do this to ensure that they have complete control of their online assets. Moreover, using a shared IP meant that whenever there was busy traffic, their site would suffer downtime and eventual customer loss.
On day one, they sent emails to a small, highly engaged segment of their list—customers who had made recent purchases and were likely to open and interact with their emails. They gradually increased the volume over three weeks, first focusing on their most engaged audience. By the end of the warm-up period, they were reaching their full email list with high engagement metrics.
Results: The IP warm-up strategy worked. By starting small and increasing the volume and recipients of their emails, they were able to build trust with major email service providers and increase email deliverability.
Strategies for IP Warming
IP warming is more than just sending a few emails each day. Here’s what to keep in mind to ensure a smooth warm-up process:
Start with the most engaged customers: Begin your warm-up campaign with the customers most likely to open, click, and respond to your email. For example, customers who just recently bought a product or have a history of responding to specific messages are the best.
Monitor Engagement Metrics: Open rates, CTR, and other metrics help you recognize what works and what doesn’t. The idea isn’t just to send emails in batches. Your sending schedule and volume must be adjusted to ensure engagement remains at a certain level or threshold.
Use a Consistent Sending Schedule: Consistency is critical. Email providers take note of patterns, so aim to send emails around the same time each day or week during your warm-up period.
Avoid Large Volume Jumps: Do not send large volumes, as the spike can lead to ESPs shadow-banning your email and IP address. Remember that ESPs can ban your IP address, ensuring that even if you set up a new email, messages from it won’t land in the recipient’s inbox.
Authenticate Your Domain: Set up SPF, DKIM, and DMARC authentication for your email domain. Authentication builds credibility with email providers, increasing your chances of reaching the inbox. Email deliverability tools like Outreach Magic simplify domain authentication into a few easy steps.
Case Study 2
A nonprofit in Germany recently got a new email list for a campaign, and as expected, they were eager to reach everyone fast…
At first, they sent emails to the list, but soon, they realized that their emails were not landing in the recipients’ primary inbox. They got a new IP and decided to warm it up before sending too many emails. First, it was a few hundred recent donors, and engagement was solid, so they doubled the volume each day. But by week three, open rates started dropping, especially with Gmail users—a red flag for deliverability issues.
They scaled back a bit, focusing on their most engaged contacts while fixing their Gmail reputation. Once things were back on track, they resumed the warm-up and, by the end, achieved a 25% open rate. The experience taught them the value of adjusting their approach when issues arise.
Common IP Warming Challenges and How it Affects Email Deliverability
There are a few challenges you might face when warming your IP address:
Low Engagement Rates: ESPs often habitually classify your emails as spammish if they have low engagement rates. Metrics you should worry about include open rate, CTR, and link-through rates…
High Bounce Rates: High bounce rates indicate that emails aren’t reaching the intended recipients, which can damage your sender reputation. Clean your list regularly and avoid sending to contacts with previous bounce history.
Spam Complaints: If recipients mark your email as spam, this can hinder your progress. Encourage people to add your email address to their contacts or safe sender list to improve deliverability. Use Outreach Magic to find recipients who consistently mark your email as spam and remove them from your mailing list.
ISPs with Strict Filtering: Some email providers, like Gmail, have stricter filters. For these providers, take a slower approach, sending to smaller batches of engaged contacts to establish credibility.
The Benefits of a Successful IP Warm-Up
When done correctly, IP warming offers several benefits for your email campaigns:
Higher Inbox Placement: Emails are more likely to reach the primary inbox instead of being filtered to spam or Promotions.
Improved Sender Reputation: Gradual IP warming builds a positive sender reputation, which benefits your future campaigns.
Enhanced Open and Click Rates: With better email delivery, more people see and engage with your content.
Long-Term Deliverability Success: Proper IP warming sets a solid foundation for maintaining a positive sender reputation over time.
Case Study 3
A SaaS company was gearing up to launch a big product update and wanted to spread the word to their entire user base…
By the end of the month, they were reaching their full email list, and the results were impressive. Their open rate shot up by nearly 30% compared to past campaigns. The “slow and steady” approach paid off by building trust with email providers, ensuring their emails landed right in customers’ inboxes instead of getting sidelined as spam.
Conclusion
IP warming might seem like a minor detail, but it’s actually a game-changer for successful email deliverability. By building trust with email providers step-by-step, you’re setting yourself up for better deliverability, higher open rates, and, ultimately, a bigger impact…
These days, email marketing isn’t just about what you’re saying; it’s about how you’re sending it. And IP warming? That’s the “how” that can make all the difference. Whether you’re a scrappy startup, a nonprofit, or a big company, taking the time to warm up your IP could be the hidden key to getting your emails where they need to go.
Ready to make sure your emails reach the right inbox? With Outreach Magic’s IP warm-up tools and expert insights, you’ll build trust with email providers and keep your messages out of spam. Start your free trial today and watch your email deliverability soar.
