Email Deliverability Guide: Best Practices to Avoid The Spam Folder And Improve Your Email Efficiency

Imagine a postman. His job seems straightforward enough but just because he picks up a batch of letters in the morning doesn’t mean they’ll magically end up in the recipients’ hands. He has to navigate through a maze of wrong addresses, locked gates, and maybe even the occasional unfriendly dog to make sure each letter gets to the right mailbox. 

In the digital world, dispatching an email is pretty similar. Hitting the “Send” button is just the beginning. To make sure your message lands in the recipient’s inbox and not in the dreaded spam folder (or worse, gets lost in the ether), you’ve got to pay attention to a bunch of different factors when planning out an email campaign or an event-based workflow.

Whether it’s a personalized offer, a transactional confirmation, or a cold email you send, you don’t want it marked as spam.

Just like our diligent postman, you need to be on top of things like authentication protocols, the quality of your email content, how engaged your recipients are, and your sender reputation. In this article, we’ll look closely at all these nuances and give you practical tips to boost your email deliverability and make your campaigns more effective.

Understanding email deliverability 

The concept of email deliverability isn’t as straightforward as it may seem. Much like admiring a beautiful painting, the closer you look, the more details you begin to notice, and the more intricate its components become. Metrics such as open rate, bounce rate, or CTR are directly related to deliverability, but the concept itself involves some additional nuance.

In the world of email marketing, we often talk about the delivery rate – a metric that tells you whether a message was successfully handed off to the recipient’s server. While this is an important step, it doesn’t yet signal full success. It’s similar to a package being delivered to the right building, without anyone confirming whether it reached the correct door.

The true measure of effectiveness is the inbox placement rate – the percentage of emails that land in the main inbox, bypassing folders like spam, promotions, or other secondary categories. This is the metric that most accurately reflects actual email deliverability, and improving it should be the goal of any professional campaign.

You can have the most compelling, beautifully designed email, but if it’s misclassified by inbox filters, it will likely go unread and as a result, fail to deliver the intended outcome. True deliverability means not just arriving at the server, but being actually visible to the recipient.

Properly understanding the difference between an email being delivered and it actually landing in the primary inbox is more important than ever. Only with proper placement can you truly speak of a successful email marketing campaign.

Best practices for high email delivery rate

Internet service providers use sophisticated spam filters and spam traps to protect their users from unwanted communication and identify senders who use email in illegitimate ways. Understanding the interplay between sender reputation, IP reputation, and domain reputation, as well as their impact on message deliverability is key.

Dedicated infrastructure vs. Shared infrastructure

Choosing between dedicated and shared infrastructure is one of the first decisions you’ll need to make for your email marketing strategy. Each has its advantages and the choice will depend on your specific needs and goals.

✅ Dedicated infrastructure pros

• Ideal for high volume: If you’re sending a large volume of emails, a dedicated infrastructure is often the better choice. It provides you with full control over your server’s reputation because only your actions affect it.
• Enhanced deliverability: With a dedicated IP, you can build and maintain a strong sender reputation. This is crucial for maximizing deliverability, as email providers are more likely to trust messages coming from a reputable IP.
• Control and customization: Having your own infrastructure means you can customize settings and configurations to better suit your email strategy, further enhancing deliverability and performance.

✅ Shared infrastructure pros

• Cost-effective: Shared infrastructure can be more affordable, making it an attractive option for smaller businesses or those just starting with email marketing.
• Ready-to-roll: If you don’t send emails very frequently, shared infrastructure allows you to jump right in with a pre-warmed IP, avoiding the time-consuming process of warming up a new IP address.
• Sufficient for lower volumes: For businesses that send emails infrequently or at lower volumes, shared infrastructure can be perfectly adequate while still offering decent deliverabilit

Sender reputation vs. Server reputation

These two concepts are closely connected in the context of email deliverability and may overlap to a degree, but it’s still important to have a clear understanding of what they’re about at the core.

➡️ Sender reputation

Sender reputation is a metric that email service providers use to determine the trustworthiness of a sender, based on factors like engagement rates, sending frequency, compliance with best practices, and the absence of spammy content.

• Control and practices: Sender reputation is something you have more direct control over through your email marketing practices. This includes factors like how often you send emails, your engagement rates, and your compliance with email marketing best practices. Good habits, such as avoiding spammy content, maintaining clean email lists, and sending relevant content, can help build a strong sender reputation.
• Domain reputation: A critical component of your overall email sender reputation is your domain reputation. This is influenced by the quality of the messages you send from your domain. Consistent, high-quality email practices improve your domain reputation, which can positively affect your email deliverability.

➡️ Server reputation

Server reputation is a measure of the trustworthiness of an IP address used to send emails, based on its history of sending behavior, spam reports, and overall email quality, which directly impacts deliverability.

• IP address impact: Server reputation, on the other hand, specifically pertains to the IP addresses used to send your communications. This is particularly important when using shared infrastructure. If your email server IP addresses have been flagged for spam or poor practices, it can negatively impact your email deliverability, regardless of your own sender reputation.
• Shared infrastructure risks: Using shared infrastructure means that your email deliverability can be affected by the actions of others sharing the same server. If other users have poor practices, it can drag down the server’s reputation, affecting your campaign performance. Conversely, if you share an infrastructure with reputable senders, it can help boost your deliverability if your own sender reputation is less established.

Email provider diversification affecting email deliverability

Email providers aren’t carbon copies of each other in terms of how they operate, and their rules can vary significantly. This is especially important to consider because different providers are prominent in different countries and regions. For instance, while Google and Yahoo! dominate globally, Europe’s most popular providers also include Outlook, Onet, GMX, Wirtualna Polska, Orange, Yandex, and Seznam.

Recent research, backed by solid data up until June 2024, shows that Gmail holds a whopping 35.99% of the global email user market share, while Yahoo Mail accounts for 2.85%. Combined, these two email clients cover 38.84% of the market. Given this significant share, understanding and complying with their specific policies is crucial for ensuring high deliverability.

At the beginning of 2024, Google and Yahoo! introduced policy changes that directly impact email deliverability on their platforms. These included stricter spam filters, enhanced authentication requirements, and a stronger emphasis on engagement metrics such as the mandatory inclusion of a one-click unsubscribe option. To maintain a high deliverability rate, you must adapt your practices accordingly, especially if a significant portion of your contact base uses these two services.

Of course, complying with Google and Yahoo’s guidelines is now a must for anyone running bulk email campaigns. However, it’s equally important not to overlook the smaller mailbox providers, of which there are many across Europe’s highly diversified market.

While these providers may not always publish clear deliverability standards like the global giants, they still build their own reputation-based filtering systems that can significantly affect your campaign performance. One way to support strong deliverability in these cases is by obtaining CSA (Certified Senders Alliance) certification – a recognized trust signal used by many operators. MessageFlow can assist you in meeting the necessary requirements, increasing your chances of successfully reaching recipients, regardless of their inbox provider.

What else contributes to a good email deliverability rate?

Alright, so we’ve discussed a number of fundamental deliverability issues that affect your campaigns. Deciding on the type of infrastructure you want to use and taking into account the different types of reputation are email marketers first steps but there are more factors to consider. 

1. Authentication

Implementing SPF, DKIM, and DMARC email authentication protocols, now mandatory for services like Gmail, is the foundation of strong deliverability. Proper configuration confirms the authenticity of your messages, protects against spoofing, and builds the sending domain’s reputation. The so-called domain alignment ensures that SPF, DKIM, and DMARC mechanisms are consistent with the sending domain, which is crucial in the eyes of spam filters.

It’s also worth considering to implement BIMI, a protocol that allows a verified brand logo to be displayed in the recipient’s inbox. This not only acts as a visual trust signal but also provides an additional layer of authentication that boosts the credibility of your communication.

➡️ How can you easily check if your emails are properly authenticated?

The simplest way is to use a built-in feature in Gmail. Send a test email, then open it in your Gmail inbox, click on the three-dot More menu in the top-right corner, and select Show original. A new window will display the authentication status of SPF, DKIM, and DMARC. Gmail clearly shows whether each of the protocols has passed or failed.

A helpful complement to this is using tools like Mailchecker, which analyze email headers and highlight any issues with authentication. Alternatively, you can use online tools that examine the DNS records of your sending domain to check whether your SPF, DKIM, and DMARC entries are properly configured and up to date.

2. User engagement

User engagement is crucial and depends on the quality of your message. This starts with an enticing email subject line and preheader text. extends to email copy, and includes, and includes other elements like graphics and CTA. However, there’s never a guarantee of engagement, as it ultimately lies in the recipients’ hands. Currently available data puts the essential open rate for B2C emails at 19.7%

3. Low level of spam complaints

Minimizing spam complaints is crucial, as high complaint rates can damage your sender reputation. Among the policy changes mentioned earlier, providers are increasingly sensitive to users expressing their dissatisfaction, making it essential for you to keep your audience happy and thus maintain high deliverability.

4. One-click unsubscribe feature

Including a one-click unsubscribe feature is now among the mandatory policy changes. Not only does it comply with recent regulation changes but also reduces spam complaints by allowing users to easily opt out, thereby improving your sender reputation and deliverability.

5. Typos and poor email list hygiene

Typos in your email addresses can negatively affect deliverability by generating bounced email. Cultivating database hygiene is absolutely crucial, especially in the light of the database decay, which degrades your contacts list by 25% a year. Typos make a contemptible contribution to this process and although they’re not something you have direct control over, it’s best to keep your email list clean to weed out the metric spoilers. Working on clean and accurate addresses helps maintain a good sender reputation.

How to improve email deliverability for better email marketing

Improving your email deliverability and finding ways to optimize can be a challenging task, but you’ve got options. You can either dig into your email marketing tool’s analytics to try to understand what’s working and what’s not, then supplement your conclusions with insights coming from Google Postmaster Tools, Mailchecker or other email deliverability tools. These resources can help you monitor your email and shed light on how your campaigns are performing, pointing to where you might need to tweak things.

But sometimes it helps to bring in the experts. Sitting down with your email service provider reps can be a game-changer. Having numerous campaigns under their belt, they can help you analyze your current setup and spot areas for improvement. 

Use the best email infrastructure and skip the spam folder

Entrusting your email marketing campaigns to experts who know exactly what they’re doing can make all the difference. At MessageFlow, we’ve spent the last 20 years perfecting our infrastructure with integrated tech solutions, direct partnerships with email providers, and a growing team of specialists dedicated to ensuring your messages are not just sent, but delivered and impactful.

We understand the nuances of local markets and have direct connections with email providers, giving us a unique edge in optimizing deliverability across different regions. Our platform offers detailed analytics to help you understand your campaign performance and scale accordingly. We also have communication experts at your service, ready to provide assistance aimed at improving your email marketing efforts.

With our powerful API, you can integrate MessageFlow with your CRM, CMS, or marketing automation tools. Whether you’re in ecommerce, retail, fintech, or running a marketplace, our solutions cater to both marketing and transactional emails, ensuring all your communication needs are met.