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Email Deliverability Checklist: A Proven 13-Step List To Improve Inbox Placement

Email deliverability is the measure of the success an email marketer has in getting their emails into subscribers’ inboxes. It’s a critical aspect of any email marketing strategy because it directly impacts your engagement metrics and overall campaign effectiveness. In this comprehensive guide, we’ll cover the key factors that influence email deliverability and provide you with actionable strategies to maximize your chances of landing in the inbox. From maintaining a clean email list, warming up your email account, personalizing your emails, to monitoring your performance, you’ll learn how to navigate the complex landscape of email deliverability effectively. Let’s delve in and discover how to boost your email deliverability and make every email count.

What Is An Email Deliverability Audit?

An email deliverability audit is a comprehensive analysis of various factors that can impact the ability of your emails to reach the inbox of your recipients. It involves thoroughly examining your email practices, infrastructure, and performance metrics to identify potential email deliverability issues that might impair your inbox placement and suggest improvements.

After an email deliverability audit, you should have a clear understanding of any issues impacting your deliverability and specific recommendations on how to fix them. It’s advisable to conduct such an audit regularly, especially if you notice a decline in your email performance metrics, or if you’re planning to scale up your email program.

13-Step Email Deliverability Checklist

Here’s a comprehensive 13-step checklist to improve your email deliverability:

Authenticate Your Emails

Authenticating your emails is vital in ensuring deliverability as it signals to ISPs (Internet Service Providers) that your emails are legitimate and not harmful. The three primary mechanisms for email authentication are SPF, DKIM, and DMARC.

SPF (Sender Policy Framework)

SPF helps prevent spammers from sending email on behalf of your domain. You can create an SPF record in your Domain Name System (DNS) settings to specify which mail servers are allowed to send email for your domain. When an email is received, the receiving server can check the SPF record of the sending domain to make sure the email was sent from an approved server. If not, the email might be marked as spam or rejected.

DKIM (DomainKeys Identified Mail)

DKIM provides an encryption key and digital signature that verifies that an email message was not faked or altered. When you send an email, your server will generate a unique DKIM signature for it. On the receiving end, the incoming mail server uses the sender’s public DKIM key (listed in their DNS records) to check if the email’s DKIM signature is correct. If it is, the email is considered authentic and will likely land in the recipient’s inbox.

DMARC (Domain-based Message Authentication, Reporting & Conformance)

DMARC is built on top of SPF and DKIM. It ties the two protocols together with a consistent set of policies. A DMARC policy allows a sender to indicate that their emails are protected by SPF and/or DKIM, and tells a receiver what to do if neither of those authentication methods passes – such as to reject the message or quarantine it. The receiver can then send a report back to the sender about messages that pass and/or fail DMARC evaluation.

In addition to setting up authentication protocols (SPF, DKIM, DMARC) for improving email deliverability, it’s also essential to establish a custom tracking domain for various email clients like Gmail, Outlook, and GoDaddy. This helps maintain your brand’s credibility, enhance email deliverability, and avoid getting put in the spam folder.

Maintain a Good Sender Reputation

Maintaining a good sender reputation is crucial for ensuring your emails reach the intended recipient’s inbox.

Sender reputation, or IP reputation, is a score that Internet Service Providers (ISPs) assign to outgoing mail servers. It’s like a credit score for your email sending practices. This score is used by email providers to determine whether to accept, reject, or categorize your email as spam. Factors affecting this score can include:

  • Spam Complaints: If many email recipients mark your emails as spam, it negatively impacts your sender reputation.

  • Email Bounces: Both hard bounces and soft bounces can affect your reputation. A hard bounce is a permanent failure due to invalid address and soft bounces are temporary failure due to reasons like full inbox. Keep your email list clean and up-to-date to minimize bounces.

  • Email Volume: Sudden spikes in email volume can trigger spam filters. It’s better to maintain a consistent volume.

  • Blacklisting: If your IP address gets blacklisted (usually due to suspected spam activity), it significantly impacts your reputation.

  • Email Engagement: Low open and click-through rates can negatively impact your reputation, while high engagement can improve it.

To monitor your sender reputation, you can use tools like Sender Score by Return Path, which provides a numerical score representing the health of your email sender reputation. Another tool is Google’s Postmaster Tools, which provides data about your high-volume sending activities and how Gmail users perceive them.

Avoid practices that can damage your reputation, such as:

  • Sending to purchased or scraped email lists. It’s your responsibility to ensure the quality of your prospect base, confirming that you have accurate names, company information, and verified email addresses.

  • Ignoring unsubscriptions or opt-out requests.

  • Using misleading subject lines.

  • Sending too many emails too fast (without warming up your IP).

  • Neglecting to authenticate your emails (using SPF, DKIM, DMARC).

You can significantly improve your email deliverability by paying careful attention to your email practices and keeping your sender reputation healthy.

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Test Before You Send

The practice of testing emails before sending them is crucial to improve your email deliverability. By utilizing email preview tools, sending test emails, and leveraging email deliverability services you can see exactly how your email appears in different inboxes, across various devices, and detect any potential issues before your subscribers do. 

Various tools allow you to preview how your email will look in different email clients and on different devices. MailGenius offers a built-in email testing tool. Always make sure to send a test email to yourself and some colleagues if possible. Different perspectives can help catch issues you might have missed.

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Mail Deliverability Issues

Remember, testing is not a one-time task. It should be done for every email you send, especially if you’re trying new formats or designs. Consistent inbox placement testing helps you avoid mistakes, improve your email content, and ultimately, enhance your email deliverability.

Here are a list of inbox testing tools you can try to improve your deliverability.

Maintain Email List Hygiene

Maintaining email list hygiene is an essential aspect of improving email deliverability. An unclean list can lead to high bounce rates when you send and low engagement, which can harm your sender reputation and affect your overall deliverability.

Here’s how to maintain your email list hygiene:

  • Remove Invalid Email Addresses: Invalid email addresses lead to hard bounces, which negatively impact your sender reputation. Regularly cleaning these addresses from your list helps to minimize this issue. Most email marketing platforms provide automatic tools to help identify and remove invalid email addresses.

  • Prune Unengaged Subscribers: If a subscriber hasn’t opened or clicked on your emails over an extended period (often 6 months or a year, depending on your email frequency), they’re considered unengaged. These subscribers can drag down your engagement rates and affect your reputation. Consider sending an email re-engagement campaign to these subscribers, and if they still don’t engage, it might be best to remove them from your list.

  • Respect Unsubscribes and Bounce Backs: When a user unsubscribes from your email list, remove them promptly. Ignoring unsubscribe requests can lead to spam complaints, which harm your sender reputation. Also, pay attention to bounced emails. If an email address consistently bounces back your emails, it’s best to remove it.

  • Use a Double Opt-in Process: A double opt-in process requires new subscribers to confirm their subscription, usually via a confirmation email. This helps to ensure that your subscribers genuinely want to receive your emails, reducing the chance of spam complaints, and it also verifies that the email address is valid. Always get clear permission from people before adding them to your list. Use a double opt-in process for better list hygiene.

  • Regularly Update Your List: Over time, people change jobs, create new email accounts, or abandon old ones, making regular updates crucial. Aim to review and clean your email list every few months for best results.

By following these steps, you can maintain a healthier email list, which can lead to improved email deliverability, better engagement rates, and more successful email marketing campaigns.

Use a Reputed Email Service Provider (ESP)

Your choice of Email Service Provider (ESP) can have a significant impact on your email deliverability. ESPs provide the infrastructure for sending large volumes of emails, and their practices and reputation can influence whether your emails reach the recipient’s inbox or get flagged as spam.

Here’s why a reputed ESP is important and what to consider when choosing one:

  • Infrastructure & Deliverability Rates: A reputed ESP will have robust infrastructure and strong relationships with ISPs. This translates to high deliverability rates because ISPs trust emails coming from these providers.

  • Authentication Tools: A good ESP will provide tools or guidance to help you set up email authentication protocols such as SPF and DKIM records as well as DMARC. These protocols help verify your emails’ credibility and improve their chances of reaching the inbox.

  • Reputation Management: Trusted ESPs have stringent policies to maintain their reputation. They usually have strict anti-spam policies and ensure their users comply with email laws and best practices. This means emails sent through these ESPs are less likely to be flagged as spam.

  • Monitoring & Reporting: Reputed ESPs offer comprehensive analytics and reporting features, providing insights into your email performance, including open rates, click-through rates, bounce rates, and more. This data is essential for monitoring and improving your email deliverability.

  • Customer Support: ESPs with a strong reputation often have excellent customer support. They can assist with any deliverability issues you encounter and guide you in optimizing your email practices.

Examples of well-known ESPs include Mailchimp, SendinBlue, Constant Contact, GetResponse, among others. When selecting an ESP, consider factors such as your budget, the size of your email list, the features you need, and the ESP’s reputation and deliverability rates. Remember, the ESP is an important partner in your email marketing strategy, so choose wisely.

Avoid Spam Trigger Words

Spam filters have evolved significantly over the years, and they are now much more sophisticated than simply flagging specific words. They take into account numerous factors when determining an email’s spam score. However, certain words and phrases, especially when used excessively, can still trigger these filters and affect your email deliverability.

Here are some guidelines to avoid triggering spam filters with your content:

  • Avoid Overused Sales Language: Words and phrases frequently associated with promotional content or aggressive marketing, such as ‘free’, ‘buy now’, ‘discount’, ‘earn $’, ‘guarantee’, ‘risk-free’, ‘special promotion’, etc., can trigger spam filters when used excessively. This doesn’t mean you can’t use these words at all, but try to use them sparingly and within a context that provides value to the reader.

  • Stay Away from Deceptive Language: Any language that can be construed as misleading or deceptive is likely to raise flags with spam filters. This includes phrases like ‘this is not spam’, ‘confirmed’, ‘passwords’, etc. Always aim to be transparent and honest in your communication.

  • Careful with Sensational Language: Using excessive punctuation, all caps, and sensational phrases like ‘once in a lifetime’, ‘you’re a winner’, etc., can make your email look spammy. Write your emails in a natural and conversational tone.

  • Beware of Financial and Medical Claims: Certain industries are more heavily scrutinized due to past abuses. If your email contains financial claims (e.g., ‘earn extra cash’) or medical claims (e.g., ‘lose weight now’), it’s more likely to trigger spam filters.

Also using too many exclamation points or ALL CAPS can come off as spammy and decrease your deliverability. Keep your language natural and engaging.

Warm Up Your Email Account

Warming up an IP address of an email account, especially a new one, is a crucial step to ensure optimal email deliverability. This process involves gradually increasing your sending volume over time, which helps establish a positive sending reputation with Internet Service Providers. Here’s how to approach this:

  1. Start Small: Begin by sending out a small number of emails per day. This could be as few as 10-20 emails, depending on the provider.

  2. Gradually Increase the Volume: Over the course of several weeks, incrementally increase the number of emails you send each day. This could be an increase of 10-20% per day, again depending on your provider’s guidelines.

  3. Engage Your Most Active Subscribers First: For best results, initially send emails to your most engaged subscribers. These are the people who are most likely to open and interact with your emails, which sends positive signals to ISPs about your sending behavior.

  4. Monitor Your Performance: As you’re warming up your account, closely monitor your engagement email metrics. Pay attention to open rates, bounce rates, and spam complaints. If you notice issues, such as a high number of bounces or spam complaints, it could be a sign that you’re increasing your volume too quickly or that there are other issues with your emails that need to be addressed.

  5. Maintain Good Email Practices: Throughout the warming-up process, continue to adhere to all the best practices for email deliverability. This includes maintaining a clean email list, avoiding spam trigger words, and authenticating your emails.

  6. Use an Email Warm-up Service: If you’re sending high volumes of email, you might consider using an email warm-up service. These services automate the process of gradually increasing your sending volume and can help ensure you’re following best practices.

Remember, warming up your email account aims to establish a positive sending domain reputation. It’s not a one-time process, but rather something you should be mindful of as long as you’re sending emails. If you maintain good email practices and continue to monitor your performance, you’ll be well on your way to achieving high email deliverability rates.

Use a Dedicated IP Address

Using a dedicated IP address for your email sending can have a significant positive impact on your email deliverability. An IP address is a unique identifier for devices in a network, and in email terms, it’s the ‘address’ from which you send your emails.

Here’s why a dedicated IP address can be beneficial:

  • Control over Sender Reputation: A dedicated IP address means you’re the sole user of that IP for sending emails. This gives you complete control over your sender reputation because it isn’t affected by the actions of others. If you’re on a shared IP, and another user sends spam or gets blacklisted, it could negatively impact your deliverability too.

  • Consistent Email Volume: ISPs like to see consistent sending patterns. If you’re on a shared IP, the sending patterns can be erratic due to the activities of multiple senders. With a dedicated IP, you can maintain a regular email sending schedule, which can improve your relationship with ISPs.

  • Ideal for High Volume Senders: If you’re sending high volumes of email (typically 100,000+ per month), a dedicated IP is often recommended. High volumes of email can lead to deliverability issues on a shared IP, as it can be harder to maintain a good sender reputation.

However, it’s important to note that having a dedicated IP address also comes with responsibilities. Since you have control over your sender reputation, you need to ensure that you follow best practices for email sending, maintain a clean email list, and warm up the IP if it’s new.

Also, while a dedicated IP offers many benefits, it might not be necessary for all businesses. Smaller senders who don’t have a regular, high-volume sending need may do perfectly well on a shared IP, especially if it’s managed by a reputable ESP that enforces good sending practices among all its users.

In short, whether you should use a dedicated IP or not depends on your specific email sending needs and practices.

Segment Your Email List

Segmenting your email list is a critical strategy for improving email deliverability. By grouping your audience into distinct segments based on specific criteria, you can send more personalized, relevant, and targeted emails, leading to higher engagement rates and better overall deliverability.

Here are some ways to segment your email list:

  • Demographics: Segment based on factors like age, gender, location, and more.

  • Behavior: Segment according to past behavior, such as previous purchases, website activity, email engagement, and so on. It’s best to use an email marketing platform with a built-in behavior tracker.

  • Email Engagement: Segment your audience based on their interaction with your emails, such as those who regularly open your emails versus those who rarely do.

  • Lifecycle Stage: Segment subscribers based on where they are in the customer journey, for instance, new subscribers, active customers, dormant customers, etc.

  • Interests: If you have information about your subscribers’ interests or preferences, this can be a powerful way to segment.

Remember, the key to successful segmentation is to continually monitor and adjust your segments as necessary. Over time, your subscribers’ behaviors and preferences may change, so it’s important to stay responsive to these changes to maintain the relevancy and effectiveness of your emails.

Balance Promotional Content

Balancing promotional content with non-promotional elements is an important aspect of managing email deliverability. Email service providers and their associated algorithms scrutinize emails to determine whether they are primarily promotional or offer valuable content to the recipient. These algorithms don’t just tally the promotional words used; they assess the percentage of the email that is promotional versus informative or engaging.

The ratio of promotional to non-promotional content is important because ESPs want to ensure a positive user experience for their customers. If an email is heavily skewed towards promotion, it could be perceived as spam or simply unwanted by the recipient. This can lead to the email being filtered out by spam filters or the recipient marking it as spam, both of which can harm your sender reputation and influence email deliverability.

Personalize Your Emails

The personalization of emails is a highly effective strategy to improve email deliverability. By including elements tailored to each recipient, your emails become more engaging and relevant, reducing the likelihood of them being marked as spam and increasing the chances of being opened and read.

Here are some ways to personalize your emails:

  • First Name Personalization: This is the most common form of email personalization and involves including the recipient’s first name in the email, typically in the subject line or greeting.

  • Behavioral Personalization: Use data on the recipient’s past behaviors, like purchase history or browsing behavior, to personalize your email content. This could involve recommending products similar to those they’ve bought before or offering discounts on items they’ve viewed.

  • Segment-Based Personalization: As mentioned earlier, segmenting your email list allows for more targeted personalization. For example, you might send different content to long-time customers than to new subscribers.

  • Event-Triggered Personalization: Send personalized emails based on specific events, such as birthdays, anniversaries, or milestones in the customer journey (like one year since their first purchase).

To make personalization possible, you’ll need to collect and use data about your subscribers responsibly. Always ensure you’re complying with privacy laws and best practices, and give your subscribers the option to opt-out if they wish. By doing so, you can create a more personalized and effective email strategy, improving not just deliverability but also customer engagement and satisfaction.

Monitor Engagement Rates

Monitoring engagement rates is vital for improving email deliverability. Key metrics like open rates, click-through rates, and bounce rates can provide valuable insight into your email performance, allowing you to adjust your strategy as necessary.

Here’s why these metrics matter and how to interpret them:

  • Open Rates: This is the percentage of recipients who open your email out of the total number of emails delivered. It’s a basic measure of how successful you are at getting recipients to open your emails. A low open rate could suggest problems with your subject lines, send times, sender reputation, or audience targeting. There are also many things you can do to increase open rates.

  • Click-Through Rates (CTR): An email CTR is the percentage of recipients who click on a link in your email out of the total number of emails delivered. A high CTR generally means your content is engaging and relevant to your audience. If your CTR is low, it might suggest your email content isn’t compelling enough, or your calls-to-action aren’t clear or enticing.

  • Bounce Rates: This is the percentage of your emails that could not be delivered to the recipient’s inbox. Bounces are categorized as “hard” (permanent delivery issues, such as an invalid email address) or “soft” (temporary delivery issues, like a full inbox). High bounce rates can damage your sender reputation, so it’s essential to identify and resolve the issues causing bounces. This often involves maintaining good list hygiene by removing invalid addresses and regularly updating your list.

Monitoring these metrics is just the first step. The crucial part is to use this data to improve your email strategy. If your open rates are low, experiment with different subject lines or send times. If your CTR is low, test different types of content or calls-to-action. If your bounce rate is high, clean your list to remove invalid addresses.

It’s also important to consider these metrics together. For example, a high open rate coupled with a low click-through rate might suggest that your subject lines are compelling, but your email content is not living up to expectations.

By regularly tracking these metrics and making data-driven adjustments, you can continually improve your email deliverability and overall email marketing success.

Check Your Email Server Settings

Checking your email server settings is a crucial part of improving your email deliverability. This involves ensuring that your server is correctly configured, including setting up a reverse DNS and registering for ISP feedback loops. Here’s how these work and why they’re important:

  • Reverse DNS Setup: A Reverse DNS (Domain Name System) lookup is a process by which an IP address is linked to a domain name. In the context of email deliverability, setting up a Reverse DNS can help validate that the email is coming from the domain it claims to be from. It is a method that ISPs use to check for email spoofing (a technique often used in phishing scams where the sender address is faked). If your server’s IP address doesn’t match your domain, your emails may be marked as spam.

  • ISP Feedback Loop Registration: ISPs offer Feedback Loops (FBLs) where they will notify you when recipients mark your emails as spam. This information is crucial because high spam complaint rates can harm your sender reputation and impact your deliverability. By registering for FBLs, you can monitor your spam complaint rates and take immediate action if they start to rise. This can include reviewing your email content, ensuring you’re only sending to opt-in subscribers, or removing recipients who frequently mark your emails as spam.

To check your email server settings, you’ll likely need access to your hosting or server account and some technical knowledge. Some Email Service Providers (ESPs) may handle these settings for you, or you may need to contact your web host or IT department for assistance. Remember, maintaining your server settings is not a one-time task, but something you should periodically review to ensure your email deliverability remains high.

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