Email marketing deliverability: 25+ tips to reach the inbox

Deliverability Yesterday, I posted about the strange findings from Econsultancy regarding email deliverability, so I decided to make a follow-up post with over 25 tips.

They come from several posts and interviews on this blog. You will find the links to those posts below.

So, after you have read this post you can go and check them all out. Or you can simply go through our email deliverability section. Here we go.



Email design and content tips

  • Make sure your content doesn’t trigger deliverability red flags, namely by using an unrecognized “from” name or a poor text-to-graphics ratio. Use less than 60% HTML/graphics, test your emails before any big campaign (renderability), and use a recognizable and listable “from” name to encourage white lists.
  • Apply the KISS principle: keep your emails as simple as possible. Avoid using capital letters and bright colors. A colored background ensures a higher spam score. Don’t get all flashy. If you use rich media or video, make sure that you work with an ESP or other partner that provides the tools you need to include them the right way.
  • Check the content of your mails on typical spam features. Try to avoid as much as possible words such as “free”, “cash”, “bonus” etc. There are several tools that are used for e-mail spam filtering based on content-matching rules. You can use them yourself to see how they work. Normally, your ESP should also be able to provide you a tool or at least a list to check the content (and even your email as such) in order to avoid getting blocked.

The email recipient: engagement and permission tips

  • Know where each email address originated and make sure the subscriber provided clear consent to receive email from you.
  • White paper: seven strategies for improving deliverability

    Avoid common pitfalls and learn reputation building tips related to list hygiene, complaint rates, email authentication and delivery.

  • If you work with a third party, perform some due diligence beforehand to understand where and how they obtained their email addresses, and if they properly disclosed how those email addresses would be used.
  • Know your recipient. If you get demographics of your subscribers, you will have a sizable advantage over email marketers who don’t.
  • Permission is not enough; list engagement list is the key to deliverability. ISPs have stated they’re measuring such things as viewing time.
  • Drop the noreply@. Gmail’s begun testing turning on images for senders who have received two replies from a user; other ISPs should follow.
  • Let the customer drive. From the onset and through Preference Centers let them dictate how much and what sort of email they want to receive.

  • Make sure you track engagement metrics to be sure you only send email subscribers want to read. And ask your email subscribers what they want!
  • Stop marketing, at least occasionally. Actual content is likely to score better as ISPs look at engagement and complaints when filtering.
  • When subscribers are satisfied and enjoy the messages, they are less likely to complain. Sending email to people that really want to receive it and having low complaint rates, has been and will stay very important for inbox placement.

Email marketing authentication

  • Implementing authentication methods like SenderID and DKIM is a must for email deliverability. These techniques are used at the receiving end to check if a sender really is who they say they are. Authenticating has an additional benefit, by using these techniques companies battle phishing and protect consumers.
  • Authentication will continue to be a major factor. Senders who have not adopted DKIM as their auth method of choice should do so this year.
  • Just like DKIM, domain-level reputation is on the rise. For portability’s sake, make the From: and Friendly From as consistent as possible.
  • Even though engagement, DKIM, and domain-rep may be on the rise they’re not the only factors. IP-based reputation still matters — a lot.

Frequency and personalization tips

  • ESPs can do many things but your content and frequency aren’t among them. What/when/how you mail is largely dependent on your deliverability.
  • Sending less is more. Contrary to popular belief, it’s not about sending more email. In fact, you should send less mail that is more relevant to your subscribers. Relevance drives engagement, which drives response so concentrate on sending only email that matters.
  • Test, test, test. Day of the week, time of day, frequency and level of personalization and segmentation will all improve engagement and pay dividends.
  • When you improve the relevancy of your messages by using segmentation and targeting and custom content, you will see much improved response rates.

Email list hygiene and guideline tips

  • List hygiene is incredibly important: make sure to not only regularly remove bounced email addresses, but also look at who is engaged. If you have subscribers that never open, click or buy your offerings, it is not worth keeping them on your list. You want a healthy, active file. Check in with your subscribers. Ask them what they like and don’t like.
  • Perform regular list hygiene. Your goal is to maintain an active, healthy file so carefully track the activity level of your subscribers. Manage your lists carefully. Of course you always ask permission prior to sending an email. Use double opt-in subscription where possible. Tell new subscribers from where the email will be sent and ask them to add it to their trusted senders list of their spam filter. Keep your lists up-to-date. Remove email addresses that don’t exist anymore and look at your bounces.
  • Sending email to a lot of addresses that no longer exist (hard bounces) is a red flag for ISPs. They see this as spam-like behavior, because spammers don’t bother to process hard bounces either. So, a company should make sure that their user base is ‘clean’ and hard bounces are deactivated.
  • The more engaged your subscribers are the more likely you are to drive response. Consequently, inactive subscribers tend to complain more, which can drive down your inbox placement rates. To get an engaged user base, companies should be transparent at the opt-in process, manage user expectations and deliver relevant content, giving customers control over their data and preferences. 
  • In many companies, different branches have different client email lists. It’s not all done in marketing, for instance,as other departments can engage clients in different ways. This depends on the size of your company, but the idea here is pretty simple. Create core guidelines for your whole company on permission and list building services.

ISPs and ESPs

  • ISPs determine inbox placement based on the reputation of the sender. Therefore, following best practices that reduce complaint rate, unknown user rates, and spam traps hits is an email marketing imperative.
  • Select an ESP or technical partner who is familiar with the problem of spam and has the right technology available. It is very difficult for you as a marketer to control all technical aspects of spam filters.
  • Respecting receiver’s wishes is getting even more important as various ISPs have implemented, or are implementing several engagement metrics into their reputation systems. Are emails opened and do people click in them?

Based on these posts (and more deliverability posts):

Email deliverability: don’t always blame the ESP, here’s what you can do!
Scott Hardigree’s email deliverability challenges in true Twitter-style
Email deliverability: an interview with Return Path’s Mario Marlisa (part 1)
Email deliverability: an interview with Return Path’s Mario Marlisa (part 2)
Common email delivery myths
Email marketing and deliverability: an interview with Reputy
Email marketing tips: 5 ways to get your email delivery rates higher
4 more ways to get your email delivery rates higher

Bookmark and Share

Join me on Twitter

Join me on Facebook

Join me in the Social Marketing Forum

Subscribe to the newsletter



1 thought on “Email marketing deliverability: 25+ tips to reach the inbox”

Comments are closed.