10 Ways to Improve Email Deliverability

Struggling with email deliverability? Here are ten tips that can help you get better results when sending emails.
If you've ever sent out an email blast to your customer list only to find that half of them never received it, you know how frustrating low email delivery rates can be.

That's why we're here today—to help every marketer improve their email deliverability and get the most bang for their buck with every campaign.

We'll show you 10 simple tips that will ensure your emails are as successful as possible, so no matter how big or small your audience is, they all receive the message!

1- Keep a Consistent Sending Schedule

A critical factor in improving email deliverability is the consistency of your email campaigns. Email service providers closely monitor the regularity of your email sending schedule when deciding whether your emails land in the inbox or spam folder.

Inconsistent email sending can lead to sending spikes, which are abrupt increases in the number of emails you send at once. These spikes can trigger alarms with spam filters and have a negative impact on your sender reputation.

The timing and frequency of your email campaigns are of paramount importance. The right timing and frequency depend on various factors, including your industry, the type of email campaign, and your recipients' behavior. For example, marketing emails may have different optimal send times compared to transactional emails.

Consider industry-specific data when setting your sending schedule. Research from Brevo, for instance, suggests that different industries may have specific optimal days and times for sending emails. Aligning your sending schedule with these industry best practices can increase the likelihood that your emails are opened and engaged with.

Maintaining a steady sending frequency is crucial for eliminating erratic email bursts. This consistency helps gain the trust of email service providers, as they see your email sending as more reliable and less likely to be associated with spammy behavior.

By adhering to a regular sending schedule that suits your audience and industry, you not only boost your email deliverability but also increase the chances of your emails being noticed and acted upon.

2- Avoid Spam Traps

Spam traps are a lurking threat in the world of email marketing. These are email addresses deliberately created by Internet Service Providers (ISPs) and email community organizations to identify and apprehend spammers in the act of sending unsolicited emails. If you unknowingly send an email to a spam trap, it's an immediate red flag, and your sender reputation may take a significant hit.

Getting off a deny list, once you've been flagged, can be an arduous and time-consuming process. Therefore, it's in your best interest to steer clear of spam traps altogether. This is an essential aspect of maintaining a healthy sender reputation and improving email deliverability.

To safeguard your email marketing efforts from the perils of spam traps, it's vital to maintain a clean email list. Regularly clean and update your list to ensure it consists of engaged and consenting users. Avoid purchasing email lists at all costs, as these often contain stale, unverified, or potentially compromised email addresses, making you more susceptible to falling into the spam trap.

In addition to these preventive measures, consider implementing authentication protocols like DMARC, DKIM and SPF, which can further enhance your email's credibility and reduce the chances of your emails being flagged as spam. Remember, a vigilant and ethical approach to email marketing is your best defense against the insidious threat of spam traps.

3- Monitor IP Reputation

As your email volume grows, it becomes essential to have the proper email infrastructure in place. When you reach the milestone of sending around 25,000 daily emails, it's advisable to transition to a dedicated IP address. However, it's not as simple as just switching IPs. A critical step is properly warming up the new IP address to establish trust with Internet Service Providers (ISPs).

ISPs rely on filters to defend against spam, and you need to prove that your IP is a trustworthy source of wanted email. To do this, begin any email campaign cautiously by sending small batches of emails. These should be directed to addresses of known engaged users in your list. As these emails are received and opened by engaged recipients, your IP gradually builds trust with ISPs.

Slowly increasing the volume of emails you send allows your IP address to acclimate to the heightened sending frequency. The ISPs become more confident in the legitimacy of your email campaigns. This warming-up process is a proactive strategy to maintain a solid IP reputation.

Remember, a tarnished IP reputation can lead to emails being filtered as spam or even blocked altogether. Regularly monitoring and nurturing your IP reputation is essential for consistent email deliverability, ensuring that your emails continue to reach your target audience's inboxes and not their spam folders.

4- Avoid Spam-Trigger Words

These "spam-trigger" words can be present in your subject lines, preheader text, or the email body itself, and they're like red flags for spam filters, often leading to your email being relegated to the junk folder.

Some examples of common spam-trigger words and phrases include enticing calls to action like :
  • "Claim your discount NOW!"
  • "Act immediately"
  • "Jackpot"
  • "100% FREE"
  • "For only XXX amount"

It's not just about words; certain formatting and elements can also be problematic. Avoid using characters like ", >, and ! in your subject lines, as these can be perceived as spammy.

Your subject lines hold immense power in determining whether your emails get opened, and despite advancements in ISP filtering systems, it's prudent to steer clear of these common spam phrases. Even though not all of them will guarantee your email's banishment to the spam folder, minimizing their use is a wise tactic to bolster your email's chances of reaching your recipients' inboxes.

Additional things to steer clear of:
  • Characters in subject lines like ", >, !, etc.
  • Writing in ALL CAPS
  • Symbols or exaggerated numbers like 777, $$$, 0% risk.

5- Write GOOD Emails

Crafting emails that not only capture the reader's attention but also provide genuine value is a fundamental strategy for improving email deliverability. The quality of your email content directly influences engagement and can be the key to securing a coveted spot in your recipient's inbox.

Engaging emails, those that captivate readers and offer something of value, are the ones that recipients look forward to. This anticipation signals to ISPs that your emails are appreciated, increasing the likelihood of them landing in the inbox.

When seeking to improve email deliverability, it's essential to please two parties: ISPs and your recipients. However, by prioritizing the satisfaction of your audience, you inherently take care of the ISPs' concerns. ISPs ultimately aim to protect the end-user, and if they see that your recipients are content and engaging with your emails, they are more likely to regard your email sending practices positively and continue placing your emails in the inbox.

To achieve this, it's crucial to provide content that your recipients enjoy and find valuable. Incorporating elements like interactive AMP widgets, such as shopping carts, quizzes, spin-the-wheel games, polls, and embedded forms, can further enhance engagement and keep your audience interacting with your messages.
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6- Cleanse & Segment Your List

Nobody enjoys receiving generic, impersonal, and irrelevant emails. The solution lies in segmenting your email subscriber list based on various criteria, including:

  • Demographics: like gender, age, and occupation
  • Geography: factors like country and city
  • Behavioral data: such as past interactions and engagement levels
  • Buyer's journey: awareness stage, consideration stage, or decision-making stage
  • Customer's lifecycle stage: new or existing customers, frequent buyers, loyal customers.

Segmentation ensures that your emails are more targeted and resonate with the recipient. When you put in the effort to create content that aligns with a subscriber's interests and needs, it reflects positively on your email's performance. Combining segmentation with personalization can lead to a significant increase in email engagement, ultimately boosting your deliverability rate.

However, it's equally crucial to avoid letting inactive and unengaged subscribers linger on your list. The longer they remain, the greater the risk to your reputation and deliverability rates. Providing an easy way for users to unsubscribe from your emails is important, but regular list cleansing is also vital.

Regularly removing inactive recipients is crucial to prevent a high bounce rate, which can harm your sender credibility. High hard bounce rates, caused by sending emails to non-existent users, can quickly trigger filtering and blocking on your IP. Employing email validation services to eliminate duplicates, typos, outdated domains, do-not-email records, and other common user errors is a proactive step in maintaining a clean and responsive email list.

7- Use Double Opt-In

This process involves sending a follow-up email to subscribers after they've signed up, asking them to confirm their desire to receive email communications from you. Subscribers who willingly go through this confirmation process are more likely to be engaged and fully invested in your emails.

With double opt-in, you're assured that your email list is populated by individuals who genuinely want to hear from your company. They have actively expressed their interest, which translates into a higher likelihood of open rates and engagement.

The way you collect email addresses plays a substantial role in your deliverability rates. An optimized opt-in process ensures that your email list is composed of engaged users who want to receive your messages. When you send emails to people who didn't agree to receive messages or were unaware, you risk being marked as spam. ISPs may even view you as a sender who's spamming everyone on your list, including those who genuinely want your emails.

The common single opt-in method, where users agree to receive emails with a simple checkbox, may seem convenient for building your list, but it can lead to an abundance of spam complaints. Spam complaints are harmful, as some ISPs may start blocking sending servers after just a few reports per one thousand emails. To defend against spam complaints and maintain a clean and engaged email list, the double opt-in approach is recommended.

In some regions, like several European countries, double opt-in has become a mandatory requirement due to its effectiveness in reducing spam and ensuring that email marketing remains permission-based and respectful of recipients' preferences.

8- Include a Clear Unsubscribe Link

If the unsubscribe process is confusing or difficult, it can lead to subscriber frustration and, in some cases, result in your emails being marked as spam, which can be harmful to your deliverability rate.

A best practice in email marketing is to provide an easily accessible and clearly labeled unsubscribe link or button in all your email communications. This empowers subscribers to opt out effortlessly if they choose to do so. In addition to a visible unsubscribe link, it's crucial to structure your emails with enough white space to minimize the chances of users inadvertently clicking on unintended links while trying to unsubscribe.

By making the unsubscribe process straightforward and user-friendly, you reduce the likelihood of subscribers resorting to spam complaints. It's a proactive approach that respects subscribers' preferences and contributes to a healthier email marketing ecosystem.

9- Test Emails Before Sending

There's an array of email clients and mobile devices to consider, each with its unique way of rendering emails. Mobile devices are especially significant, as a substantial portion of people, approximately 53%, read their emails on these devices. To maximize your email deliverability, it's crucial to ensure that your emails display correctly across various email clients and devices, particularly the ones your audience favors.

While it may seem time-consuming to test your emails for all available email clients, you should prioritize testing them for the ones most frequently used by your subscribers.

For instance, according to research, the top five email clients include:

  • Apple iPhone's Mail app
  • Gmail
  • Apple iPad's Mail app
  • Google Android's Mail app
  • Outlook

If your email marketing tool offers the option, take advantage of email preview features to see how your email appears in different email clients and devices commonly used by your audience.

Sending a test version of your email before sending the final one is a critical step in ensuring that your email functions as intended, appears correctly, and offers an optimal viewing experience for all recipients.

10- Warm-Up Your Email

When it comes to warming up your email for optimal deliverability, using a specialized email warm-up tool like Unfiltered can be a game-changer. We are designed to help establish a positive sender reputation and ensure your emails reach their intended recipients' inboxes.

Unfiltered offers a comprehensive and efficient warm-up process tailored to your email needs. By gradually increasing your email sending volume to a recipient's list with your own email copy, this tool helps you build trust with Internet Service Providers (ISPs) and improve email deliverability.

Our user-friendly interface and features make it a valuable asset in your email marketing toolkit. It's all about ensuring your emails are seen and opened, and using Unfiltered is a smart and practical approach to achieving that goal.


Improving your email deliverability doesn’t have to be hard.

Making sure you stick to email best practices and testing your campaigns will help ensure that more emails land in the inbox over time.

But with Unfiltered, you can take it a step further by using our automated warm-up process to gradually build trust with ISPs. Buil especially for email marketers, you can be sure your emails get opened more often and reach the intended recipient.

Try Unfiltered today and see increased email deliverability!
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