How To Design Your IP Warming Campaigns

The relationship between email senders recipients is more complex than most people think. Email Service Providers provide a critical service for companies to message the inbox of consumers and businesses both for transactional messaging (purchase receipts, shipping notifications, account status updates, etc.) and for marketing messaging.

IP Reputation

Every email originates from an IP address on the Internet. And every recipient is sent the message through their mail server. The vast majority of consumers utilize services like Gmail, Hotmail, AOL, and other email services to check, receive, and send email on. The vast majority of businesses use hosted solutions like Google Business or Office 365 to host and manage their email.

Because of the proliferation of SPAM on the Internet, these services monitor the reputation of the sending IP address to block or route the communications coming from those servers. They may also enlist third-party monitoring services to monitor sender reputations. And, they do their best to verify that the sender’s domain is sending from an authorized IP address.

It’s not a clean science, though. Many companies that do a great job of managing an opt-in database of subscribers for marketing and have a great customer-base they need to send transactional sends to have their emails blocked altogether, or unknowingly routed to junk mail folders of their consumer or business recipient. And attempting to resolve the issue can be frustrating because the majority of Internet Service Providers have turned to automation and algorithms to resolve the IP Reputation of the sender.

Email Deliverability

A new industry was born, the email deliverability industry. Now, companies must monitor their IP Reputation and inbox placement to ensure their emails are properly delivered to their recipient. There are a few scenarios that companies must monitor and take action on with respect to their email deliverability:

  • New IP Address – if you start up with an Email Service Provider or are sending bulk email through your own mail system, the ISP or the third-party they work with to look up your IP address doesn’t have any history of your IP address ever sending. As a result, you may be blocked or directly routed to the junk folder.
  • Blacklisted IP Address – perhaps your mail server was hacked or your IP address was spoofed and subsequently blacklisted for sending SPAM. The ISP will likely block any email coming from your IP address… and they may not even tell you that they’re blocking it.
  • Shared IP Address – unless you specify that you wish to have a dedicated IP address, you’re likely going to be put on a shared IP address with other email senders with your Email Service Provider. This can be advantageous if the other senders have great reputations. It can also be a disadvantage as the ESP may be very sensitive if you have any spam complaints or are sending to bounced email addresses. It’s sometimes infuriating that a good sender can be shut down by an ESP and have to prove they were not sending SPAM. And, in the meantime, your business can suffer greatly.
  • Poor IP Reputation – you may not even realize it, but if you’ve been reported for SPAM by subscribers, or you import a list that has a SPAM trap email address, your ability to get to the inbox may be significantly hampered. This may even happen because of the content that you’ve provided, not even a complaint! The poor IP Reputation may be associated with one or more ISPs, or a third-party platform.

A great IP reputation is critical to the success of your company’s ability to message its subscribers… so companies often find themselves in the unfortunate situation where they need to migrate to a new IP Address to build a new IP reputation. Or, your company may be migrating from one ESP to a new ESP and need to warm-up the new IP address. In any case, the migration of your email to a new IP address will require IP warming.

What is IP Warming?

IP Warming is the process where a company ramps up its email sends gradually to establish an IP reputation with each of the ISPs and to avoid getting blacklisted on third-party reputation management systems.

Why IP Warming Is Necessary?

IP Warming is necessary because every new IP address that sends bulk email is assumed to be a spammer by Internet Service Providers. Ignoring your IP Reputation will destroy your email deliverability, resulting in:

  • Risk of spam traps and spam complaints destroying your new IP reputation.
  • Third-party blacklisting by email firewall services.
  • Routing your email to junk folders instead of the inbox.
  • Throttling of your messages to collect additional engagement data.
  • Disabled sending from your Email Service Provider.

You’ve spent a lot of time, resources, and money to acquire your subscribers… and having low open and click rates on the critical messages that you drive your business with is both costly on direct revenue as well as the time and cost to repair your IP Reputation.

According to an eMarketer study, the median email marketing return on investment  is 122%. That’s four times higher than any other digital marketing channel. Why would a company put this at risk?

IP Warming Schedule

Salesforce recommends the following schedule for warming up an IP address for consumer recipients:

IP Addresses Warming Recommendation by Domain
ISPs & Domains Day 1- 3 Day 4-5 Day 6-7 Day 8-14 Day 15-21 Day 22-28 Day 29+
AOL & Yahoo 20,000 20,000 20,000 40,000 80,000 160,000 320,000
Microsoft 20,000 20,000 20,000 40,000 80,000 160,000 320,000
Google / Gmail 5,000 10,000 20,000 40,000 80,000 160,000 320,000
ATT 20,000 20,000 20,000 40,000 80,000 160,000 320,000
Spectrum & Charter 20,000 20,000 20,000 40,000 80,000 160,000 320,000
Cablevision 20,000 20,000 20,000 40,000 80,000 160,000 320,000
Comcast 20,000 20,000 20,000 40,000 80,000 160,000 320,000
Apple 20,000 20,000 20,000 40,000 80,000 160,000 320,000
All Others 20,000 20,000 20,000 40,000 80,000 160,000 320,000

As well, they recommend that you also have a daily maximum send across ISPs:

IP Address Warming by Daily Max
Day Daily Max Volume
1-7 50,000
8-14 100,000
15-21 200,000
22-28 400,000
29-35 800,000
36+ 1,600,000

IP Warming Subscriber Data

So… just take your subscriber data and then segment it out for these campaigns and you’re good to go? No! The subscriber data and recipients are critical to your IP Warming success:

  • Bounces – If you send email addresses that bounce, you can immediately trip and destroy your IP reputation. We highly recommend utilizing an email intelligence engine to scrub your email addresses to remove likely bounces before sending.
  • Spam Traps – Your data likely has spam trap email addresses. These are very old email addresses that are no longer in use by the original owner and have been recycled for use. ISPs use these email addresses to detect senders that may have outdated or purchased subscriber lists. An email intelligence engine will scrub your email addresses to remove known spam traps.
  • Temporary – There’s an industry of services out there that you can sign up for and receive a temporary email address to get through a registration gateway to the information you need. Temporary email addresses typically have no opens or clicks associated with them and you don’t want to be sending to them. Using an email intelligence engine will scribe your email addresses to remove known temporary email addresses.
  • Engagement – If you’re building an IP reputation, you want to prove to the ISP that these subscribers aren’t just opted-in, that they’re engaged as well. Segmenting your list to subscribers who have recently opened or clicked through on your campaigns should be prioritized in your campaigns.

IP Warming Domain Data

While the big ISPs are great for segmenting and sending your IP Warming campaigns, there are a plethora of other domains that you will be sending to. If you’re a B2B company, a majority of your list may not even be associated with the top ISPs listed above by email address. in fact, the resources you’ll find online on IP Warming don’t typically include international nor B2B domains in their recommendations.

  • Hosted Email – consumers and businesses alike are now utilizing services like Google or Microsoft to host their personal or corporate domain. For example; is hosted on Google… so it’s susceptible to Google’s ISP standards for developing an IP reputation. This has to be incorporated into your send volumes as you’re ramping up.
  • Spam Firewalls – corporate email systems often subscribe to third-party spam firewalls that prevent email from unknown sources from getting through. It’s a great idea to avoid these firewalls during your IP Warming.
  • Aliases – different ISPs offer the ability to alias email addresses. As a result, you may be sending multiple, identical emails to the same inbox, a process that should be avoided.
  • Other – Many domains incorporate other methodologies when receiving email addresses – from providing false response codes, to not responding altogether. These domains should be filtered out and avoided under your IP Warming campaigns.

IP Warming Reputation

As you continue to send your IP Warming Campaigns, monitor how your IP Reputation is progressing. This can be done using a number of services:

  • SenderScore – Validity’s SenderScore is a measure of your reputation, calculated from 0 to 100. The higher your score, the better your reputation, and typically the higher the chances of your email being delivered to the inbox rather than the junk folder. SenderScore is calculated on a rolling 30-day average and ranks your IP address against other IP addresses.
  • BarracudaCentral – Barracuda Networks provides both an IP and domain reputation lookup via their Barracuda Reputation System; a real-time database of IP addresses with poor or good reputations.
  • TrustedSource – run by McAfee, TrustedSource provides information on both your domain’s email and web reputation.
  • Google Postmaster Tools – Google offers its Postmaster Tools to senders allowing you to track data on your high volume sending into Gmail. They provide information including IP reputation, domain reputation, Gmail delivery errors, and more.
  • Microsoft SNDS – Similar to Google’s Postmaster Tools, Microsoft offers a service called Smart Network Data Services (SDNS). Among the data provided by SNDS is insight into data points like your sending IP’s reputation, how many Microsoft spam traps you are delivering to, and your spam complaint rate.
  • Cisco Senderbase – Real-time threat data on IP, domain, or networks to identify SPAM and malicious email sends.

IP Warm

With IP Warm, we incorporate our own proprietary domain intelligence to prioritize and segment corporate domains along with ISPs to properly schedule your IP Warming campaigns. By sending to your most engaged subscribers and avoiding these pitfalls, a company can ramp up its IP Warming campaigns and establish an IP Reputation within weeks that will solidify its email deliverability.

Our process will save hundreds of hours in complex segmentation, prioritization, and campaign optimization from your team. Upload your subscriber list and we’ll utilize email intelligence, domain intelligence, and email engagement to optimize your campaigns for your IP Warming. If you’re moving to a Shared IP, we’ll ensure your list is clean and won’t get you into trouble with your ESP. If you’re moving to a Dedicated IP, we’ll deliver your cleansed data, optimized lists, and campaign schedule to ramp up your IP reputation and maximize your deliverability!

Get Started with IP Warm