Email Deliverability: Best of the Best Practices

Your audience list is carefully curated, your email flow steps are ready to fire and you’re just one click away from sending your next impactful email campaign… but wait, is there something preventing your hardwork from ever seeing the light of the inbox?  

After putting the time and effort into building out your email campaigns, the most important factor is that your email actually makes it to your subscriber’s inbox. Without ensuring that, your catchy subject line and beautifully designed HTML simply won’t matter. 

Below we lay out key steps to optimizing your email deliverability and maximizing your reach by covering three key areas you should know about email deliverability:

  • What deliverability is and why it matters
  • Major factors that affect deliverability and how marketing automation platforms can help with some of the heavy lifting
  • 7 best practices you can implement to improve your deliverability 

What is email deliverability?

You can’t improve email deliverability without first understanding what it means. Often when we think about email deliverability we consider the email delivery rate (ie 98% emails delivered). 

Deliverability is the rate at which emails arrive at the inbox, not just those emails that are delivered. The difference here is important. Your emails can have a great delivery rate, and still not be making it to the inbox. 

Maybe only 2% of your emails are bouncing, but actually an additional 10% are making it to the Email Service Provider (ESP) server and then being pushed into a SPAM folder. Sometimes deliverability rates can block out entire ESPs. For example, if gmail flags you, all your emails that are currently sent to a gmail inbox could be going to SPAM, which may equate to a significant portion of emails that will never be read by your subscribers. 

ESPs and IT teams are always on the lookout for SPAM to keep emails out of subscribers’ inboxes that they deem irrelevant or potentially a security risk. If your email is flagged as SPAM continuously, this potentially significantly lowers your deliverability rating and can further damage your sending reputation. 

Why deliverability matters

You’re most likely not coding, designing and meticulously writing and proofreading emails just for fun, right? 

You (or your marketing team) are most likely creating emails with a purpose: upsell a new product, announce an upcoming webinar to get more attendees, overall provide value to your subscribers. 

If your emails look like they’re being “delivered” (not bouncing) but they’re never actually making it to the inbox, your subscribers never get the chance to engage, and you just wasted a lot of effort for an email that will auto delete in a SPAM folder in 30 days. That’s not going to get you closer to that upsell goal, or that webinar attendance goal. No one wants that!

Major factors that affect email deliverability

So it’s clear you want your emails delivered to the inbox so you get the chance to meet your marketing goals. 

There are a few hoops your emails need to jump through first in order to get there. You can distill the inbox deliverability of your emails down to three areas: authentication protocol, reputation and email content. 

Authentication Protocol

The first step of deliverability is confirming that you are who you say you are. ESPs use Sender Policy Framework (SPF), Domain Keys (DKIM), Reverse DNS and Domain-Based Message Authentication, Reporting, and Conformance (DMARC) to verify your sender identity. These protocols prevent spammers from forging your email address and passing off messages on your behalf. 

SPF and DKIM can be configured with most major market automation platforms (including Marketo, the platform we use, support, and love at Leadous). If you’re sending high volumes of email, go through this process (you will likely need the help of your Network Administrator) to configure and prove your sender authenticity. 

Reputation

Your reputation is the next factor in deliverability. This is calculated based on how trustworthy your emails are to subscribers. A number of factors play in here, including whether your IP has been blacklisted or reported as spam, the percentage of bounces in your email list, and engagement levels of your subscribers. 

You can use tools like https://www.senderscore.org/ to closely monitor your reputation metrics. Sender score will look at your IP address’s “sender reputation including spam complaints, how many unknown users you email, if you’re on any industry blacklists, and more.” By keeping an eye on all these factors, you can more closely hone in on where you may need to improve your deliverability strategy for reputation management. 

Email Content

The last factor affecting your email deliverability is the actual email content. Whereas authentication protocol and reputation are partly out of your control and up to ESPs and subscribers to determine, optimizing your emails for deliverability is 100% within your control. 

Optimizing your email content for deliverability involved avoiding spammy subject lines (a lot of punctuation and capitalization is out; clear, simple language is in). Everything down to the images, content, links and code making up your email are analyzed for a deliverability rating. 

How Marketing Automation Platforms Help With Deliverability

As a Marketo Engage platform partner, we’re going to focus on the best-in-class features Marketo has, but we can confidently say that many marketing automation and email marketing platforms have some type of email deliverability support. 

Talk to your marketing automation platform provider about their deliverability features. Many platforms have built in tools to test your emails for clean code and images or subject lines that could get flagged as spam, and even help you preview your emails across different ESPs to make sure it’s rendering correctly. For Marketo customers, check out this article on the email deliverability features they support. 

Best practices to improve your deliverability 

  1. Institute a deliverability initiative 

Improving your deliverability starts by taking up a clear initiative to monitor, manage and improve on existing deliverability. Make deliverability a central tenant of your email marketing strategy, not a side project that you look at for a month and never look at again. It’s an ongoing process. Create a standard email deliverability checklist that you can go back to for every campaign. Set recurring checkpoints to go back and monitor success. 

  1. Clean your data 

Much of your deliverability rating will come back to the quality of your subscriber lists. If a significant portion of your lists are unengaged, this will lower your deliverability rating. Consider archiving subscribers who haven’t engaged in 60 or 120 days, or simply segment them out for a “last chance” nurture and allow them to choose whether they re-opt in or not. Keeping stagnant subscribers in your lists who never open your emails sets you up for possible spam flags and lowers your success rate.

Sidenote: cleaning your lists also means taking a look at where you are getting your subscribers from. Stop buying lists. We’ll say it again, stop buying lists! Purchased lists (with no verified opt in) can seriously harm your deliverability with spam traps at worst, and will likely be completely unengaged from your emails anyway, also harming deliverability ratings. 

  1. Segment your audiences

Related to cleaning up your audience data, also consider more detailed audience segmentation. How can you ensure that the emails you’re sending are going to subscribers who will be interested and engaged? 

As an overarching example, if you have an event that is only available in a certain area – are you segmenting your audience invite list to the targeted geography? 

More granularly, when you opt in new subscribers, are you asking them what subcategories they’re interested in? Segmenting your audiences and campaigns allows you to keep your content relevant, increase your engagement, which improves your deliverability.

  1. Create engaging & personalized content 

This one seems like a no brainer, but it needs to be said. Subscribers opted in at some point to receive emails from you, so please, make sure that you’re sending the emails that they asked for!

 Keep your messages clear and provide actual value related to your business. Don’t take advantage of their trust, you’ll only receive unsubscribes, disengagement, or worse, SPAM complaints as a result. 

By taking the time to be thoughtful with your email strategy, you can ensure your subscribers will be glad to see your email hit their inbox. 

And don’t forget to test your emails before you send them. Use tools like Litmus or others included in your marketing automation platform to evaluate your deliverability rating and make sure your emails will render right across ESPs. Don’t lose subscribers from simple fixes you could’ve caught if you had just spent a few minutes testing before sending. 

  1. Launch a Preference Center 

You may not want to think about the audience members you want to unsubscribe when you’re building out your email programs, but your subscribers really need a clear way to unsubscribe. You’d much rather have an unengaged reader unsubscribe than just become unengaged or hit the SPAM button–both of which will much more negatively affect deliverability.

Beyond a clear path to unsubscribe, consider launching a preference center to help your subscribers customize their email experience with you. Let them choose subcategories they’re interested in or email frequency. It just might be what you need to get them re-engaged and subscribed to your emails! 

  1. Send consistently and not too often

Don’t overwhelm your subscribers with too many messages, you don’t want to lose their trust or interest by bombarding them with messages! Plus, if your subscriber has 4 emails in their inbox from you to wade through, chances are they will ignore some, affecting the engagement rates of those emails.

Email deliverability can also be affected by the timing of your sends. Sudden large increases or drops in email sends can negatively impact deliverability. This became an issue during the beginnings of the COVID-19 pandemic, when suddenly brands were sending massive amounts of emails to all their subscribers. Create an email sending schedule (it can be the first thing you implement with your deliverability initiative!) and stick to it. 

  1. Monitor… and then monitor again!

As you implement more best practices, your deliverability should improve, but it’s a constant ebb and flow that you need to monitor. Keep an eye on your sender scores, check blacklists and prioritize areas where you can continue to make headway on your deliverability. 

There are many factors that go into your email deliverability, some highly technical, where you’ll need the help of a network administrator to setup. Others are as simple as deleting all those exclamation points from your subject lines. No matter your technical prowess, you need to start somewhere. 

Because if you’re going to put the time, budget and hours into email marketing (which you should, since the ROI of an email is $38 for every $1 spent), then it’s a no brainer that you want that email to actually get read! Follow these initial best practices and you’ll be well on your way to inbox placement.