Email Delivery vs. Deliverability: What's the Difference?

We spend hours planning out every detail of each campaign, crafting the perfect copy and agonizing over fonts, colors, and spacing. We talk through our personas, target audiences, and messaging. We build emails from scratch or lovingly modify templates so that we’re putting our best foot forward with our email marketing campaigns.

With all the blood, sweat, and tears that go into our emails, there’s nothing more heartbreaking than finding out the message never made it to our subscribers. No matter how carefully we plan our campaign strategy, design, and development, if the email doesn’t reach the inbox, it doesn’t matter.

Making it into the inbox is one of the more ambiguous, misunderstood elements of sending great email. Marketers often mix up a key distinction: delivery vs. deliverability. Though the terms are often used interchangeably, they have very different meanings.

Email Deliverability vs. Email Delivery

Let’s start with the basics: What are we even talking about? Here are the simple definitions:

• Delivery refers to whether or not a receiver accepts your email. This comes before the inbox or spam folder distinction. Can the message physically be accepted in the first place?
• Deliverability or Inbox Placement refers to where that message ends up once it is accepted; in other words, the inbox, spam folder, or another folder.

When it comes to understanding the difference between delivery and deliverability, ask yourself these questions:

1. Can a receiver accept your message?
2. Does it get to the inbox?

Let's dive into both.

Can a receiver accept your message?

At its core, delivery refers to whether or not a receiver accepts the message you’ve sent. This comes before the spam folder is ever considered. Does the domain or email address exist? Is your IP address blocked?

Imagine your email is a busy business traveler on her way to a conference. Successful delivery would mean that the traveler arrived at the correct airport. (If anyone from New York has accidentally gone to LaGuardia instead of JFK, you know how these types of mix-ups happen!) She then proved her identity with a ticket and passport, and airport security verified her as safe to pass through security to her departure gate.

Similarly, when an email is successfully delivered, that simply means it made it to the intended recipient’s mailbox -- and that could be in the inbox or the spam folder.

Did your email get to the inbox?

Also known as inbox placement, deliverability refers to where that message ends up once it’s accepted. Did it get to the inbox?

Let's return to our travel metaphor. Our traveler has made it through security to the correct gate and now needs to get to her destination.

Deliverability is akin to where the traveler's flight ultimately arrives. While most travelers safely get to their departure gate (delivery), weather or other mishaps may reroute them, for example, from Dallas to Houston (deliverability).

Deliverability consists of three parts:

1. Identification: This is the set of protocols that prove you are who you say you are when you send an email, such as Sender Policy Framework (SPF), DomainKeys Identified Mail (DKIM), and Domain-Based Message Authentication, Reporting, and Conformance (DMARC). Each of these terms function like your passport, license, or background check. Are you Jane Doe, the hard-nosed lawyer from upstate New York? Or Jane Doe, the collegiate swim coach from southern California? Your ability to get on the correct flight to your intended destination hinges on your identity.
2. Reputation: Your sender reputation is essentially a score that signals how trustworthy you are. Each organization and internet service provider (ISP) might have different scores for you. Generating positive subscriber behavior, like engaging with your email or marking you as a trusted sender, is the best way to boost your sender reputation -- which you can do by sending relevant, personal emails to your subscribers.
3. Content: Is your message appropriate for your audience? Is it relevant? Are you combining copy like “Make money fast!” and “Work from home” with poor sending practices like buying an email list (noooooo!) or preventing unsubscribes? Using excessive exclamation points, weird formatting, and URL shorteners can all impact your email's deliverability based on your previous sending patterns. Think about it from your subscribers’ perspective. If you receive an email with the subject line, “MAKE MONEY TODAY!!!!”, are you really going to open it? Tailor your message to what your subscribers care about to make the most impact.

Identification and reputation account for most of the reason an email lands in the inbox or the spam folder. Think about waiting in line for an airport security screening. If you don’t have a ticket, you won’t make it past the first desk. And if you’re on the no-fly list, you’re not going anywhere.

Delivery issues mean that something may be wrong with your infrastructure, you’ve got faulty email addresses on your list, or you've received enough negative user interaction to warrant a block. Deliverability issues indicate that your sending and permission practices might be out of whack, or your email list is generally disinterested in your content.

How to Make It to the Inbox

Now that you know the difference between email delivery and deliverability, what does this mean for your marketing strategy? Here are three best practices to ensure your messages make it to subscribers' inboxes.

1) Make your list squeaky clean.

Even though we love permission-based marketing, when it comes to emails, permission can expire. A large number of inactive subscribers can dramatically impact your deliverability because they offset your engagement metrics. Consider removing or suppressing inactive customers after a set time or automating a re-confirmation campaign.

If you’re having deliverability issues, it’s possible your list includes spam traps, which look like real email addresses, but are used to identify spammers. Sending to one can indicate poor list hygiene or spammy acquisition practices, like buying and renting lists or scraping email addresses off the internet.

Removing invalid emails on a regular basis and re-confirming your inactive subscribers can help declutter your list.

2) Make it easy to unsubscribe.

It’s a common myth that unsubscribes are bad, but there’s no evidence that unsubscribes and unsubscribe rates via the direct unsubscribe link in your email affect your deliverability. In fact, it can actually help by boosting your subscriber engagement and cleaning up your email list. If you’re sending targeted campaigns to people who want to receive your emails, then you’re bound to increase opens and clicks, and decrease your bounces.

Don’t hide your unsubscribe button. Make it clear and easy to find in your email, whether that be in the footer or at the top. Streamline the unsubscribe process so that it’s one step -- otherwise, you’re fighting a losing battle against the dreaded “report as spam” flag.

3) Make your emails personal and relevant.

Marketers and subscribers often define spam differently. Subscribers don’t think in terms of spam filter testing or algorithms, but in terms of relevance. Are you sending content that matters to them? This is ultimately the most important question to ask yourself before hitting "send" on any email.

Email is one of the most personal channels in a marketer’s arsenal. Sending emails that resonate with your audience and leverage the 1:1 nature of the medium won’t just positively impact your deliverability; it will also boost reader engagement and build better relationships with your audience as well.

from HubSpot Marketing Blog http://blog.hubspot.com/marketing/email-delivery-deliverability