A Marketer’s Field Guide to ISPs and Deliverability

Email marketers are intensely focused on ROI for their marketing dollars. Maximizing the number of clicks, opens and conversions is the primary method that ROI is measured for most marketers. However, maximizing all of these response metrics requires that your email is delivered to your subscribers’ inbox by the ISPs (Internet Service Providers). This metric is commonly referred to as deliverability or inbox placement rate.

Since Return Path has more relationships with more ISPs than anyone else on the planet, I thought it would only be natural that we share some insights into the world’s most popular receivers to help you improve your deliverability and email ROI.

This is the first of a multipart series that will give you some valuable information about the companies who are the gatekeepers to your success. We’re going to share information about:

  • Spam Filtering
  • Engagement and Reputation
  • Sending infrastructure including authentication and rate limiting
  • Whitelisting and Feedback loop information
  • What ISPs care about

We’ll focus on Yahoo!, Microsoft Hotmail, Gmail, AOL, cable providers such as Comcast and Cox, B2B receivers such as Rackspace, Tucows, Synacor and then we’ll dive into some of the biggest international players in Europe, Asia and Brazil.

Before we start profiling each ISP individually it’s important to understand some common truths about email and receivers in general before you contact one of them to complain about your delivery issues:

  1. ISPs care more about what their customers want in their inbox than what you want in the inbox. An ISP’s revenue is driven by lots and lots of happy users of its mail service. In addition, many of the ISP abuse monitoring teams are understaffed so marketers get limited mindshare for their deliverability issues.
  2. 99 times out of a 100 a deliverability issue is not the ISPs problem but the sender’s problem. Following all of the email industry’s best practices is key to getting your email into the inbox.
  3. ISPs put a heavy weight on sender’s IP reputation so it’s important that you maintain low levels of unknown users, complaints and spam traps.
  4. Engagement data, or the actions your subscribers take with your email, is becoming more and more important. If your users are ignoring or deleting your emails without opening them that’s a red flag for ISPs.
  5. Batch and blast is a thing of the past. Sending targeted, relevant, timely and engaging email is going to get you in the inbox.
  6. ISPs will support and mediate with senders if their subscribers are actively engaged and vocal about your email delivery.
  7. More than 90% of global email is considered spam so receivers have a challenging job sorting the good, bad and ugly email. False positives can be a big headache so they will err on the conservative side and deliver questionable email so as not to prevent that bank statement or email from Aunt Marcy from getting through.

Stay tuned for the upcoming series of ISP blogs that will help you to maximize deliverability for all of your subscribers. The first is on Yahoo!

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