The Simple Steps to Improve Your Email Deliverability

Article by: Vincent van Vliet

Last update: April 18, 2025

Email deliverability measures how many of your emails are accepted by Internet Service Providers (ISPs) and successfully reach recipients’ inboxes. It’s calculated by dividing the number of delivered emails by the total sent, multiplied by 100.

A strong email deliverability rate should be above 90%, ideally over 95%. However, according to PowerDMARC’s 2024 email security report, many businesses struggle with deliverability due to authentication failures and poor sender reputation. Without proper SPF, DKIM, and DMARC setup, even legitimate emails can end up in spam or get blocked entirely. In fact, using an SPF checker reveals that misconfigured authentication is a leading cause of delivery issues—costing businesses time, revenue, and credibility.

Why does this matter? Imagine investing heavily in an email campaign, only to discover half your emails never arrived. Poor deliverability hurts open rates, conversions, and sender reputation. The good news? With the right strategies—like email authentication, list hygiene, and spam avoidance—you can significantly improve inbox placement.

Email Deliverability Challenges

We know what email deliverability can affect. But what affects email deliverability?

Authentication Issues and Their Role in Email Security

While email authentication can help prevent email spoofing and phishing and improve email deliverability, a lack of email authentication can result in a low deliverability rate.

Sender Policy Framework (SPF) specifies which IP addresses and servers are authorized to send emails for your domain. As highlighted in Google’s Email Sender Guidelines, recipient servers rigorously verify SPF records to block unauthorized senders. If this check fails, your emails may be marked as spam or rejected entirely.
DomainKeys Identified Mail (DKIM) helps to check the legitimacy of all incoming emails. The recipient’s server can see if the email has been forged in the transmission process or if it is safe to open.
Domain-based Message Authentication, Reporting, and Conformance (DMARC) helps instruct how receiving servers should deal with authentication failures. It also enables domain owners to obtain reports on authentication results.

These protocols, if implemented correctly, can help maintain a good reputation and avoid a low deliverability rate.

Sender Reputation

The sender reputation score refers to the score assigned by ISPs. If you fail to address deliverability issues on time, if you spontaneously send high-volume emails, or if your content is unengaging or irrelevant, you might get a bad score and not get your email delivered to the intended target.

Blocklists

If you fall on a blocklist (i.e., databases of IP addresses that have been flagged for spamming or suspicious activity), you might experience a very low email deliverability rate. You might fall on a blocklist because of a variety of reasons, such as not responding to unsubscribe requests, purchasing email lists, or not paying attention to your sender reputation or overall hygiene.

Spam Triggers

Some emails may come across as spammy if they contain spam-triggering language, too many images, and too little text or are simply sent on an imbalanced, irregular basis.

Bounce Rates

Soft and hard bounces take place when emails aren’t delivered. You might experience bounces when you do not consistently clean your emails from invalid or inactive addresses, do not remove regularly bouncing addresses, etc. Bounces might also happen when you do not use double opt-in, as a result of which irrelevant and invalid email addresses might appear in your email list and impact your email deliverability.

Simple Steps to Boost Email Deliverability

Here are some easy-to-implement, actionable steps to boost your email deliverability:

Keep Your Email Design Responsive

Try using responsive design templates that can be perfectly customized to different gadgets. Often, businesses use email templates that look great on PC but terrible on smartphones. Ensure your design template is good regardless of the type or size of the devices.

Speaking of email designs, it’s also important to use single-column layouts and keep subject lines under the 30-40 character limit.

Implement DMARC, SPF, and DKIM for Authentication

Making use of email authentication protocols such as DMARC, SPF, and DKIM can help you protect your domain against email spoofing and phishing attacks. This, as a result, may have a positive impact on your email deliverability rate. You can check your email authentication with online tools like an SPF checker to ensure maximum accuracy, consistency, and protection. You can also use an SPF generator to generate your record without any fee or errors.

Keep Your Email Lists Neat and Clean

Always remove inactive subscribers before they’d ‘move’ you from active subscribers’ inboxes. By inactive subscribers, we mean anyone who hasn’t engaged with your emails in the past 6-12 months. This simple yet effective action will ensure your email list is always up to date and clean of any irrelevant subscribers.

Don’t Be Spammy

Using all-caps text, excessive punctuation, and/or spam trigger language can push your emails away from the primary inbox and toward the spam folder. To avoid this, you can use a spam checker to see how well your email might potentially perform.

Provide Value

When crafting your emails, try to make the content as valuable as it can possibly be. Refrain from sales-heavy language and instead provide useful insights, actionable steps, and reliable information that people can actually trust and find value in.

Also, keep in mind that ISPs pay attention not only to your email content but also your sending practices. A balanced, consistent sending strategy is preferred over high-volume, spontaneous spikes in your sending patterns. Combine good contents with good sending habits and see improvements in your email engagement and deliverability.

Final Thoughts

While numerous factors may negatively impact your email deliverability rate, there are also many ways to boost this rate and get your message delivered to the intended recipient. Some key steps include using email authentication, cleaning your email lists, paying attention to the designs, avoiding spam-like practices, and providing value. Following these easy yet useful steps may go a long way in bringing your email deliverability rate closer to where it ideally should be.

Article by:

Vincent van Vliet

Vincent van Vliet is co-founder and responsible for the content and release management. Together with the team Vincent sets the strategy and manages the content planning, go-to-market, customer experience and corporate development aspects of the company.