Successful email deliverability can seem like a tricky task–and with so many factors affecting your sender reputation such as
content quality and email list health, getting your email to the inbox can feel harder than ever.
And if you are sending email on a brand new IP address, this variable can be one of the largest influencers of your inboxing success. If you don’t properly warm up your IP, Internet Service Providers (ISPs) such as Gmail and Yahoo may choose to not deliver your email.
This guide prepares you to get a handle on your new IP’s reputation, warm it up the right way, and improve email deliverability by providing the following:
- An IP address definition and how its reputation affects email delivery.
- A suggested warmup schedule so you can start sending email over a new IP address without experiencing email
delays or delivery failures. - A sample newsletter and transactional IP warmup approaches.
What is an IP and Why Warm It Up?
An IP address is a unique string of numbers that identifies your email domain. An IP address is one of the most important factors that determines your sending reputation.
ISPs use your IP address to identify you as a sender, track sending behavior, and assign an IP reputation score. Better behavior results in higher delivery rates.
Certainly! Here’s a bullet-point version of the content, making it easier to read:
New IP Address Challenges
When you increase your email sending volume, you may need to add additional IP addresses.
A new IP is considered “cold” because it has no reputation score, as no emails have been sent from it yet.
Importance of Warming Up:
A cold IP with zero sending reputation needs to be “warmed up” to improve email deliverability.
Warming up involves gradually increasing the volume of emails sent from the new IP.
Warming Up Process:
Start Slow: Begin by sending low volumes of email from your dedicated IP.
Gradual Increase: Systematically increase the email volume over time.
This process allows Internet Service Providers (ISPs) to recognize, identify, and evaluate your sending practices.
Goal of IP Warmup:
Ramp up your sending volume to your anticipated normal levels.
Help ISPs learn your usual sending patterns, making it easier for them to identify any suspicious behavior.
Why It Matters:
Spammers often switch IPs frequently to avoid ISP security checkpoints.
A proper warm-up signals to ISPs that your email practices are legitimate, reducing the risk of your emails being flagged as spam.
During the warmup period, ISPs evaluate your sending behavior, email list health, and how committed you are to providing relevant and valuable information to recipients. The more engagement you receive during the warmup period, the better the ISPs will favor your IP. ISPs examine factors such as how many users opened your email, scrolled to the bottom of the email, or moved your message to other folders.
As a sender, warming up your IP provides a prime opportunity to monitor and optimize your entire email campaign. You’ll also find that the good reputation you build during the warmup period makes your life much easier. Instead of chasing down problems, you can focus more closely on honing your acquisition strategy, providing stellar content, and monitoring your results
How to Warm Up Your IP
The advice and warmup schedule below is intended to be a suggestion only. Every sender is different and you may need email deliverability experts to help you determine the right warmup volume and frequency for your email program. How many emails you send during your warmup depends on your own total email volume, but you must send enough email at enough frequency so that ISPs can track your reputation.
You could choose your welcome message as your trial segment for your new IP. Welcome messages do several good things because these emails:
- Serve as a permission reminder
- Reiterate your value proposition
- Generate opens and clicks with their calls to action
If you don’t have data on how your audience engages with your emails, it’s best to start with your most recent signups. These users are usually more active right after they join your email list. As your email reputation improves and you start sending more emails, gradually include older and less engaged recipients. This is also a good time to clean up your list by removing inactive or unengaged contacts.
If you notice that your new IP isn’t performing well, with fewer people opening your emails and more blocks happening, don’t rush. Slow down your email sending to give your reputation time to improve. Warming up an IP can take up to 60 days, but most people finish the process within 30 days, and some even do it in 1-2 weeks. Use your email delivery results as a guide—if things are going well, you can speed up. But if you see signs of throttling, it’s better to slow down.
During the warmup period, pay close attention to how your audience is interacting with your emails. Low engagement rates can make ISPs stricter during this process. Take a good look at your content—are your subject lines clear and interesting? Are you sending valuable information? If your initial group of recipients isn’t responding well, chances are the rest of your list won’t either.
Maintain Warmup Across all ISPs
During the warm-up period, it’s important to keep a consistent sending volume across all ISPs. This means spreading out your emails evenly each day, so each ISP gets a similar amount. For example, don’t send to Gmail on Monday and Yahoo! on Tuesday. If your sending is inconsistent, it can make your reputation look unreliable.
Whatever type of email you choose to start with, make sure it follows clear permission practices. This helps build a good reputation and shows ISPs that you’re a legitimate sender. Once you’ve picked a segment of your audience, figure out how many emails to send. Start with a small number and increase gradually.
Warming Up Your IP: Two Simple Approaches
- Conservative Approach: Follow the IP warm-up plan and keep the same email volume as the previous day if your delivery rates aren’t doing well. For example, if you want to send 90,000 emails in a month, begin with just 50 emails on the first day and slowly increase the amount each day until you reach your goal.
- Aggressive Approach: Even if you want to ramp up quickly, start with 50 emails on the first day. Then, you can increase the number of emails by up to 10 times each day, as long as your email performance is good. This way, you can scale up faster if your initial results are positive.
Sample Transactional Email Schedule
Established Business
If your business already sends a lot of emails and you’re switching to a new email service provider (ESP) or using one for the first time, it’s important to move your emails gradually. You can do this by splitting your email traffic and slowly moving small parts of it to the new IP over time. If you have multiple mail servers, transfer them to the new IP one at a time to ensure a smooth process.
New Business
For a new business, the natural growth of your customer base usually makes it easier to warm up your IP. As your business grows, your email volume increases gradually, which helps warm up your IP. Since transactional emails depend on the number of users, this growth creates a steady increase in emails. Just make sure ISPs know these emails are transactional. It’s probably not the best time to add promotional emails during the warmup.
IP Allocation and IP Warmup Schedule
Top Tips for a Successful IP Warmup
Establishing consistent email sending patterns is crucial during your IP warmup period. Here are some key things to keep in mind before you start:
- Start Cautiously: It’s difficult to fix a bad reputation once it’s damaged. While it might be tempting to push out emails aggressively, remember that repairing a poor sending reputation can take 4 or more weeks. Every day you get blocked can be costly, so it’s better to start slow and steady.
- Avoid IP Rotation: You don’t need multiple IPs, and rotating through many IPs (a tactic known as “snowshoeing”) can backfire. If ISPs catch on, they may block your entire IP range. With proper warmup and best practices, you can send millions of emails per day from a single IP.
- Use Data to Improve: ISPs appreciate when you’re responsive to your recipients. The more data you gather, the better you can adjust your email program, even if you face delivery issues. The email community is small, and good practices will help build a positive reputation.
- Be Cautious with Marketing Emails: Marketing emails are more challenging because ISPs scrutinize them more closely than transactional emails, which are generally seen as “wanted.” It’s recommended to use at least two dedicated IPs—one for marketing emails and another for transactional emails.
- Follow Best Practices: To ensure maximum deliverability, monitor user engagement, personalize your emails, and remove inactive recipients both during and after the warmup period. This will help maintain a strong sending reputation throughout the life of your email program.