How to improve email deliverability for 2024 (Expert Guide)

Content is not the problem. The biggest misconception when it comes to maximizing email deliverability is to solely focus on optimizing content. You can have the best content in the world, but if your sender reputation is poor, your emails won’t be delivered.

What affects email deliverability the most?

A variety of factors can impact your email deliverability and trying to navigate those items can be a difficult task even with a foundational knowledge of the topic. To help, we've compiled a list of items that affect email deliverability and how you can increase your deliverability score going forward.

1) Missing Authentication

Email authentication serves as the main protocol to tell receiving mail servers that you are who you say you are. In today’s email environment, spammers will often use established sending domains to try and send abusive email. Having authentication on your domains helps prevent this by improving your domain security, and specifying what servers are authorized to deliver email from your domain.

As a bulk sender, authentication has become more important in 2024, as AOL/Yahoo and Gmail now require 3 levels of authentication on all receive email (SPF, DKIM, & DMARC). Missing any of these protocols will likely result in increased levels of spam folder placement, and potentially rejected/bounced emails.

2) New Sender Requirements

Recently, Gmail and Yahoo have added policy updates for bulk senders, more specifically the element of one-click unsubscribe.

The one-click subscribe has become a standard in email marketing, this means you can no longer have a standard landing page to try to win back customers. The best way to overcome this new policy is by focusing on improving your content relevancy.

3) Performing a Seed List Test

A seed list is a monitored set of email addresses that helps you track your inbox placement. By regularly testing your seed list helps to improve email deliverability by giving you insights into how you’re inboxing.

Seed lists are important because it can allow you to deal with a problem before there is a problem. The primary purpose of seed lists are to help you test emails across different client lists and help you detect rendering and deliverability issues.

4) Blacklisting

Blacklistings are an easy way for ISPs (Internet Service Provider) to identify potentially bad senders, and those that have had a history of sending abusive email. Blacklistings can take place at the domain or IP level. They are typically listed when your domain sends email to one of their monitored spam trap email addresses, or if a subscriber manually reports abusive email from you.

Some blacklist companies are more severe than others (Spamhaus being the most reputable). This means that not all listings will result in immediate inboxing issues; however, they do raise concerns around list collection methods and subscriber hygiene.

5) Hard Bounces

Spikes in hard bounces can be a red flag for recipient ISPs, as this will raise concerns around a marketer’s list acquisition process. Sending to email addresses that are ‘Bad’ or that are ‘Inactive’ looks suspicious, as these types of email addresses wouldn’t have recently given you permission for email communication.

You should strive to keep these percentages below 2% on a monthly basis.

6) Spam Complaints

Spam Complaints can quickly drop your reputation levels, and make it difficult to consistently land in the inbox of your recipients. In the eyes of an ISP, when one of their customers marks a received email as spam, this is their way of telling them that this email is unwanted and potentially unsolicited.

Acceptable spam complaint ratios for bulk senders are between 0.1% and 0.3% (1-3 spam complaints per every 1,000 emails sent).

7) Spam Compliance

In order to be compliant with the new bulk sending parameters for AOL/Yahoo and Gmail, you will want to keep your spam complaint ratios between 0.1% and 0.3% or below. Exceeding this threshold will likely result in inconsistent deliverability, and drops in your sender reputation.

8) Spam Trap Hits

Spam trap hits can be measured through 3rd party tools. They will typically be broken down into 3 categories:

• Pristine Traps - The most severe. These are email addresses that have never been in use, and were created with the sole intent of being a spam trap. These emails are scattered randomly throughout the internet, and are often added to subscriber lists through purchased lists, web scraping tools, etc. Sending to large quantities of these emails raises concerns around your list acquisition process not being permission based.
• Recycled Traps - Somewhat severe. These spam traps represent email addresses that were once valid and in use, but after long periods of inactivity they were abandoned and turned into a spam trap. Because these emails were once valid, they are not as severe as a pristine trap. Sending to large volumes of these traps can raise concern around your list hygiene processes. A deliverability best practice is to remove email addresses that are inactive over long periods of time. If you’re not doing this, or if you’re sending to a list of older email addresses, you are likely to see increased levels of recycled spam traps in your list.
• Typo Traps - Least severe. These spam traps represent incorrect spelling of email addresses, usually at the domain level. Verifying your email addresses at sign-up or implementing a double opt-in process will help avoid spikes in these volumes.

9) Low Engagement

Stop hoarding the data driving down your engagement score. Clean your email lists at least once a month with a verification service to improve your sender reputation.

Refer to our article on “What a healthy email list looks like” for more.

Once you've cleaned your list, you can now focus on sending highly relevant content to your audience.

Less Important Factors

There are other factors that can affect email deliverability, although they are small in relation to other factors, overtime they can greatly affect the ability for your emails to end up in a receivers inbox instead of being flagged as spam.

Domain Age

Your domain age plays a role in email deliverability. Older domains with established sending history have stronger scores and therefore are more likely to end up in a receivers inbox.

Content

This may seem like a controversial take, but in reality a great subject line only helps increase engagement if it’s seen. This is why the quality of your content is not as important when it comes to increasing email deliverability.

However, a spammy or non-compliant email title can affect your score. There are specific keywords that are flagged like:

• Free
• Buy Now
• Act Fast
• Click Here
• Make Money Fast
• Get Rich Quick
• Claim your ___
• Winner
• Pre-approved

ActiveCampaign has a great summary of keywords you should avoid.

Miscellaneous Factors

BIMI Trademark status (VMC)

BIMI, which stands for Brand Indications for Message Identification is an email specification that attaches your brand’s logo to your authenticated email messages. The purpose of BIMI is to give trusted companies and senders control over how their brand is represented in certain messaging services and with that, comes another layer of protection against phishers and scammers trying to impersonate your brand.

Ensuring high email deliverability is crucial for any organization that relies on email communication to engage with customers, drive sales, or share important information.

Need more assistance?

If your business is struggling with deliverability, navigating the complexities of an advanced tool on your own may not be the best solution. Emailable has a team of deliverability experts with over 20+ years of experience.

They can walk you through specific problems like:

• Landing in the spam folder
• Domain-specific issues
• Blacklisting
• High bounce rates
• Low open and click rates

➡️ Schedule a call with an expert