What is email deliverability? 

Each time you hit send, your emails pass through several checkpoints on the way to their intended destination. These checkpoints contain two key aspects: delivery and deliverability.

Email delivery vs. deliverability

Delivery tells you whether or not an email was received by the servers of a subscriber’s inbox provider. The message will either be accepted or bounced, with a reason why the message wasn’t accepted. 

An email is considered delivered if it did not bounce.

Deliverability is the rate at which your emails make it into your subscribers’ inboxes, instead of being labeled as spam and going to the junk folder. Think of it as the follow-up process to what happens once the message gets delivered.

Email deliverability is tricky. But the more you know—including these 33 deliverability-related terms—the more empowered you are as an email marketer.

4 ways to boost your email marketing efforts

Lay the groundwork for your email marketing efforts by ensuring your emails get delivered (and don’t land in spam). Here are four ways to set your email deliverability up for success.

1. Confirm your infrastructure and authentication

First and foremost, make sure your infrastructure is set up correctly. Confirm that you’re only sending from authenticated domains. If you send from multiple IP addresses (for purposes like segmentation), ensure they’re all authenticated domains.

Several email authentication protocols have been introduced over the past decade. 

Properly implementing the following three are vital to your deliverability foundation:

  • Sender Policy Framework (SPF)
  • DomainKeys Identified Mail (DKIM)
  • Domain-Based Message Authentication, Reporting, & Conformance (DMARC)

The objective of these protocols are to guarantee and verify the identity of the senders and protect the receivers from unsecure emails. 

2. Determine your need for IP warming

If you’re using a new IP address to send an email—or one that you haven’t used in quite some time—you may need to warm up your IP address. IP warming is the practice of gradually sending emails from a new IP address or domain name, and slowly increasing send volume until you’ve “proven” yourself as a legitimate sender.

Instances where you may want to consider IP warming include:

  • New dedicated IP with a new domain
  • New dedicated IP address with the same domain
  • New domain with the same IP
  • New subdomain from a warm domain
  • New ESP you’re using for the first time
  • Switching to a new ESP
  • Rebranding/acquisition or merger
  • Moving from a shared IP to a dedicated IP 
  • Moving from your parent domain to a subdomain just for emails
  • Planning a large spike in your typical email send volume

Do you need IP warming? We shared three best practices in How to Improve Email Deliverability and Optimize Each Send. →

3. Check in with your sender reputation

Sender reputation is a score measured from 0 to 100 that an Inbox Service Provider (ISP) gives your organization. It impacts your inbox placement, and is based on several factors like the number of emails your organization sends, how subscribers engage with your emails (based on actions like open, reply, forward, delete, and click), and how many recipients mark your emails as spam or otherwise complain about your emails.

It’s important to note that all ISPs will weigh these factors differently. Because each mailbox provider uses a unique algorithm to arrive at your score, it’s not an exact science. But, you can assume that the higher your score, the better your email reputation. 

4. Extra credit: Brand Indicators for Message Identification (BIMI)

Another step towards winning trust in the inbox is with Brand Indicators for Message Identification (BIMI). BIMI is an email standard that brings your logo into subscribers’ inboxes.

If you haven’t considered setting up BIMI yet, you may want to consider it now. In September 2022, Apple joined the list of companies implementing BIMI. BIMI support also includes several major ISPs—like Gmail and Verizon Media Group (Yahoo, AOL, Netscape). 

Dive deeper into email deliverability

We cover email deliverability in more depth in four-part guide to understanding email deliverability, How to Improve Email Deliverability and Optimize Each Send.