IP Warming


What is IP warming?

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Team Storyly
January 12, 2024
0 min read

What Is IP Warming?

IP warming is the process of gradually increasing the volume of email sent through a new or unused Internet Protocol (IP) address to establish a good sender reputation with Internet Service Providers (ISPs) and spam filters. 

When a sender starts using a new IP address, ISPs and email providers tend to be cautious and may treat the incoming email as spam or block it entirely, especially if a large volume of email is sent immediately.

To avoid this issue, IP warming is done by starting with a low volume of email sends and gradually increasing the volume over a period of time. This allows the new IP address to build trust and credibility with ISPs and email providers, who will monitor the sender's behavior, such as bounce rates, spam complaints, and engagement metrics. 

By demonstrating good sending practices, the sender can eventually achieve a high sender reputation, which leads to better deliverability and fewer emails being flagged as spam or blocked.

Types of IP Warming

There are two primary types of IP warm-ups: manual and automated. Both approaches aim to establish a positive sender reputation by gradually increasing the volume of emails sent from a new or unused IP address over time.

  1. Manual IP warm-up: In this approach, the sender manually increases the email volume based on a predetermined schedule. The sender is responsible for monitoring email sending metrics, such as bounce rates, open rates, click-through rates, and spam complaints, and adjusting the email volume accordingly. If any issues arise during the process, the sender must address them to maintain a positive sender reputation. This method provides more control over the warming process but requires a higher level of involvement and expertise.
  2. Automated IP warm-up: Some email service providers (ESPs) offer automated IP warming solutions that automatically manage the email volume increase based on predefined rules and algorithms. The ESP monitors sending metrics and adjusts the email volume accordingly, reducing the burden on the sender. This approach is more convenient and can help ensure consistent email sending practices, but it may offer less control and customization compared to a manual process.

Why Do We Need IP warming?

Warming up an IP address is necessary today because of the skepticism among ISPs. All ISPs look at email volume as a key indicator of spam attempts and will block IPs that engage in suspicious activity, including sending high volumes of emails.

Spammers often engage in the following practice: They obtain a new IP address and send emails to large numbers of recipients on a list. They will keep doing so until the ISP becomes privy to these attempts and blocks the IP address. After blocking, spammers will simply acquire another IP and repeat the process in the hopes that enough recipients will respond to their emails before ISPs block them.

Because of this, if you begin sending large quantities of emails to recipients on your contact list with a new IP, ISPs will immediately take notice. If this IP develops a negative reputation, this could severely limit deliverability. Combined with other best practices when sending emails, you'll be able to optimize your email campaigns through IP warming as you establish your IP as a legitimate sender.

How Does IP Warming Work?

IP warming works by gradually increasing the volume of emails sent from a new or unused IP address over a period of time. The goal is to establish a positive sender reputation with ISPs and email providers, which can lead to better deliverability and fewer emails being flagged as spam or blocked.

When you begin the IP warming process, you start by sending a small number of emails, focusing on recipients who are most likely to engage with your content. This may include highly engaged subscribers or customers with whom you have an existing relationship. By targeting these recipients, you are more likely to receive positive engagement metrics, such as high open and click-through rates.

Over time, you gradually increase the volume of emails sent from the new IP address. As you do so, you continue to monitor your sending behavior, engagement metrics, bounce rates, and spam complaints. This data helps you identify and address any potential issues that could harm your sender reputation or negatively impact your deliverability.

Throughout the IP warming process, it's essential to maintain good sending practices, such as keeping your email list clean, ensuring you have permission to email your recipients, and providing relevant and valuable content. These practices help build trust with ISPs and email providers, ultimately improving your email deliverability.

IP Warming Schedule

Ip Warming Schedule - Source:Sendgrid.com

IP Warming Best Practices

If you want to get started with IP warming, there are certain best practices you can implement. Keep in mind that not adhering to various guidelines could seriously compromise your IP and, subsequently, your email marketing efforts. However, you can successfully avoid these issues by taking the following steps:

Start Small and Grow Over Time

When you begin your IP warming strategy, start sending emails out in small volumes. If you send a ton of emails all at once from the start, this will be a huge red flag to ISPs and encourage them to block your IP.

As you begin sending more emails daily, you can increase the volume of emails sent each day in increments. Eventually, you'll be able to send emails at the volume you want to in order to achieve your marketing and sales goals.

Push High-Quality Content That Recipients Enjoy

To get the best results from your IP warming strategy, you should also promote top-quality content that increases the likelihood that people will engage with your emails. You can do so by carefully crafting your subject lines and email copy to entice recipients to open and read your emails. You should also effectively target your emails to ensure they go to the right people with personalized messages.

Otherwise, simply sending low-quality emails to just anybody on your contact list could hurt your chances of connecting.

Use a Specific Timeframe to Schedule Your Emails

Make sure you're only sending emails in increments based on a set timeframe. For example, you might gradually increase your email volume over the course of several days. On the first day, you would start with around 50 emails, send 50 more the next day to total 100, followed by sending 100 more on the next day, 200 on the day after that, 400 the next, and so on. Map out your schedule well beforehand to determine how many emails you'll need to send each day or week until you reach the ideal volume.

Also, send your emails at the right time to maximize the chances of people opening them. You can do so by using email features to time your emails based on recipients' time zones. For example, you might find that it's best to send emails to one segment in a particular location in the afternoons, while another might benefit from emails sent in the morning before work.

Keep Your Email Lists Clean and Compliant

You should also ensure your email lists comprise valid emails from people who've opted into your campaigns. If you're sending emails to people who aren't actively interested in your business or to un-verified emails, this could look bad to you. You may also be non-compliant with spam regulations, including CAN-SPAM, GDPR, and CASL laws.

Keep Track of Your Reputation Over Time

To prevent your IP address from suffering from a bad reputation and eventual blocking, you must monitor it throughout your IP warming campaigns. You can avoid potential issues by keeping track of the following metrics:

  • Spam Reports — Don't let your emails get past a certain SPAM rate, or your emails may not be compliant with spam laws. You'll want to reassess your campaigns and optimize accordingly if you have a SPAM rate exceeding 0.1%, which is the maximum that industry experts recommend. For instance, if you're sending an email to 500 recipients, you'll want to ensure that fewer than 50 mark the email as spam.
  • Bounce Rates — Your emails should also have a low bounce rate, which is the rate at which emails fail to reach recipients. Your bounce rate should be less than 2%, according to industry experts. If it's any higher, you should consider adjusting your email list to minimize your bounce rate, which could involve getting rid of unverified and inactive emails.
  • Sender Reputation Scores — You should also check your Sender Reputation Score or Sender Score. This functions as a kind of credit score for your emails, as SenderScore explains it. With the help of this score, you can monitor the health of your email campaigns. A Sender Score below 70 indicates that your reputation is bad. A score of 70 to 80 is better but still indicates that your campaigns need some work. If your score is above 80, you officially have a solid reputation among ISPs. When your score is high enough, you can get a certification that further establishes you as a reliable sender.

Succeed with Email Campaigns Through IP Warming

With the right IP warming strategy, you'll be able to get the results you want with your email marketing campaigns over time. Building your reputation among ISPs will help you succeed in the long term as you avoid IP blocking.

To find out how Storyly can help you supplement your email and other mobile marketing efforts, explore our solution today.


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