Mastering Email Verification & Deliverability

The most successful email marketing experts clean their lists regularly to minimize their bounces and drive their recipient engagement.

But what goes into email verification, and how do you know which tools can help boost your email deliverability?

By the end of this guide, you’ll learn about:

• Email verification and the various checks involved
• Sender reputation, IP reputation, and domain reputation
• How your reputation informs your email deliverability
• Must-do tactics for driving inbox placement and reader engagement

But first, let’s start with the basics.

What is email verification?

Email verification is the process of determining whether an email address is valid or invalid.

When an email address is valid, it indicates that it is in use by an actual person and can safely accept incoming email content. Conversely, an invalid address is any email address that cannot receive emails. These may contain typos, have errors in email syntax, or simply not exist.

Why is email verification necessary?

Email verification is an essential strategy that protects you from poor email marketing performance and a negative sender reputation. This includes high email bounce ratesⓘThe percentage of emails that are undelivered vs. delivered to the intended recipient., low engagement rates, and poor email deliverability.

When you verify your emails, sometimes called email list cleaning, you ensure your subscriber emails are valid.

More valid emails equate to a much lower email bounce rate. When your campaign successfully reaches your customers, you have a greater opportunity for recipient engagement and to improve your email marketing ROI.

What are some email verification techniques?

There are multiple techniques to aid in email verification. Prominent email verification services like ZeroBounce generally use a multi-step process that includes each of the following steps.

Syntax check

First up is a basic email syntax check.

This is the act of verifying that the email address uses the correct formatting. An email address should always contain the following parts:

There are also rules regarding which and how many characters you can use in the different parts of the email address.

For example, the email address cannot contain more than 320 characters. It also shouldn’t contain special characters or characters that break up the domain name.

If the email address fails the syntax check, it’s not valid. Typos and misspellings frequently create syntax errors, but powerful email validators like ZeroBounce can automatically resolve those for you when detected.

Domain check

After the email address passes a syntax check, beginning a domain check is worthwhile.

A domain check determines whether the email domain exists and contains valid MX or A-type records. This test will inform you whether the email domain is valid and configured to receive emails.

Domain checks are crucial for spotting fake domains and avoiding domains that do not accept incoming emails.

MX record - “Mail exchanger” record; specifies which mail server accepts incoming email messages on an email domainA-type record - “Address” record; specifies the IP address of the mail server that accepts incoming email messages on an email domain

Mailbox verification / SMTP checkⓘSimple Mail Transfer Protocol check. This is a relay process that determines if a mail server possesses the necessary DNS records to send and receive emails. SMTP checks also measure response times.

Once you confirm that the email contains the proper syntax and uses a valid domain, you can look to perform a real-time email verification check.

Simple Mail Transfer Protocol (SMTP) is an email communication protocol used to send your email to a receiving server. An SMTP check allows you to verify that the recipient's email server will accept your email message. It helps observe the response time and identify any email server configuration issues that might result in an email bounce.

Email verification services should feature an SMTP check to provide an accurate result. You’re effectively testing the email address without actually sending an email that could bounce.

Use email verification services

You can eliminate manual email verification checks by signing up for an email verification service.

These companies, like ZeroBounce, offer a low-cost email verifier to perform syntax, domain, and mailbox verification checks.

However, ZeroBounce offers additional checks to identify known spam traps and disposable email domains. These are particularly important as either email address type can be valid with the abovementioned checks.

People use disposable emailsⓘA temporary email address that users can create using a temporary email website or creation tool. You can use a disposable email address for a brief period before it expires and becomes invalid. to act as valid email addresses for a limited period. They can pass your verification checks only to become inactive later, resulting in bounced emails.

Spam traps, on the other hand, are valid, sometimes recycled email addresses. ISPs and blacklist service providers want users to email these addresses to monitor domains that aren’t using email marketing best practices - particularly email list cleaning.

Beyond using an email verifier like ZeroBounce, you should implement certain email marketing best practices, such as…

Double opt-in confirmation

The email address passed your syntax, domain, and SMTP check, and your email reads as “delivered.” But is someone engaging with the message?

Whenever you receive a new email address for your list, you should automatically email the user a confirmation message.

This offers several benefits. First, you can verify your email delivery. Second, the owner can confirm they want to receive your content. People always sign up for offers or information and may not remember signing up for your email list. This could result in spam complaints.

Do yourself a favor - implement an automated double opt-in email and verify that your subscribers want your email content.

Understanding email deliverability

Email verification checks and double opt-ins do more than just prevent bounces. They support and improve your email deliverability.

But what does that mean? After all, we know how different email verification checks stop bounces. So, what else goes into email deliverability?

What is email deliverability?

Email deliverability describes your overall likelihood of successfully delivering emails to your subscribers’ inboxes.

Avoiding email bounces is a determining factor, but more variables are at play - such as your sender reputation.

What is a sender reputation?

Your sender reputation is a numerical score given to your email domain by internet service providers (ISP).

Various factors contribute to your sender reputation, including the following:

Think of it like a credit score for your email domain. When your score is up, ISPs see you as trustworthy and are more willing to accept your email content. You're a high risk when your score is down; some may even view you as a spammer.

Email senders also have an IP reputation and a domain reputation that contribute to their overall sender reputation.

What is IP reputation?

Like sender reputation, IP reputation reflects the email-sending behaviors of a specific IP address.

Similar factors, like bounced emails, spam complaints, and poor engagement, affect your IP reputation. Conversely, verifying your email addresses and using double opt-in to confirm the subscriptions will help you build a positive IP reputation.

What is domain reputation?

On the other hand, domain reputation tracks the behavior of sent email campaigns from your specific company.

This distinction is essential as one IP can host multiple domains. The reputation of one can directly impact the reputation of the other.

Both IP and domain reputation are considered by ISPs when assessing your overall sender reputation. However, many companies will switch to a private IP to fully control their reputation.

Email content also plays a role

Apart from determining an email's validity, your email's content still plays a significant role.

After all - if people aren’t interested in your email content, they won’t interact with it.

While an unopened email is preferable to a bounced one, you still need to persuade readers to interact with the emails you send. Not only does recipient engagement influence your email deliverability, but it’s also a significant factor in driving traffic to your pages and converting readers into customers.

How to improve email deliverability

So how do we improve email deliverability?

We’ve already touched on several email marketing best practices - email verification being chief among them.

However, our five-step checklist will jumpstart your email marketing efforts and help you find the inbox more reliably.

Step 1 - Regular email list cleaning

Before you send a single email – commit to email verification.

Don’t waste time or money attempting to do it manually, either. Email verification services are available at low costs, and ZeroBounce can help you do it with 99% guaranteed accuracy.

Regular email list cleaning (roughly once a quarter) will dramatically reduce bounce rates and boost your sender reputation before you ever publish a campaign. ISPs expect senders to use best email marketing practices, including sending email content only to people that subscribe.

Moreover, email verification is an act of self-preservation as it rids your marketing team of dead-end leads like spam traps, abuse emails, and disposable emails. Your team can focus its time, energy, and budget on pursuing real potential customers instead of spammy, useless email addresses.

We also recommend using an email verification APIⓘAn API, or application programming interface, that allows an email verification tool to connect and communicate with another software application. to protect your email list in real time. This service allows you to add a company’s email verification tool to your email signup forms and automatically blocks unwanted email addresses from getting past registration.

Email authentication

Authenticating the IP and domain you use for email sending is vital to preserving your sender reputation.

Even with intelligent practices, spammers and bad actors always look for vulnerable email domains to hijack. If you’re not up-to-date on the latest email security practices like email authentication, you’re highly susceptible to spoofing – or worse.

There are three primary methods of authenticating your emails.

Method 1 - Create an SPF record

Sender Policy Framework (SPF) is a form of email authentication that lists hostnames, domains, and IPs approved to send emails on a given domain.

You create the list by creating an SPF record for your email domain. Whenever someone sends an email from your domain, the recipient email server compares the SPF record to the sender and issues a pass or fail based on the result. It’s one of several methods to stop spoofers from using your domain.

Generating an SPF record is easy and free. However, you should also use SPF along with these additional email authentication methods.

Method 2 - Create a DKIM record

DomainKeys Identified Mail (DKIM) is another email authentication method that adds a unique encrypted signature to outbound emails.

As with SPF, recipient servers check for a DKIM record anytime someone sends an email from your domain. If the sender’s email lacks the signature, the receiver rejects the message.

As spammer tactics become more sophisticated, no method is entirely foolproof. Generating a DKIM record to use alongside your SPF record is recommended. Adding more modes of email authentication will help safeguard your domain and IP reputation.

Method 3 - Create a DMARC record

Domain-based Messaging, Authentication, Reporting, and Conformance (DMARC) is yet another email authentication method that can protect your email domain against phishing attempts.

While SPF and DKIM serve as email authentication checks, DMARC is a policy that aligns the two. DMARC effectively creates a flow of operations that tells recipient email servers the next steps if a sender fails a check.

This is particularly meaningful when a technical error causes one check to fail. Rather than immediately bouncing the email, the receiver can follow the instructions in the DMARC policy to take appropriate action. For example, it can quarantine emails that fail checks so that you can monitor and assess what went wrong.

Monitor your email campaign metricsⓘUnits used to measure the effectiveness of an email campaign. Examples of metrics include bounce rate, open rate, clickthrough rate, and unsubscribe rate.

You’ve done your email list cleaning and secured your email domain. Now your email deliverability will rise without question, right?

While both steps are crucial, we must address a critical part of email marketing - email content.

So why jump ahead to email campaign metrics?

It’s tough to make intelligent decisions about adjusting your email content without any feedback from your audience. Based on how your readers sign up for your list or even the services and products you provide, you should have a firm idea of what your subscribers want to see. But that doesn’t mean your emails will be perfect out of the gate.

With your valid list of contacts, start sending out regular email campaigns. This might include a weekly newsletter, product announcements, sales promotions, etc. Then, keep a close eye on how those campaigns perform.

Here are some important industry benchmarks you’ll want to note regarding email marketing:

If you observe a higher-than-usual bounce rate, step back to your email verification process and try to identify problematic email addresses on your list. Likewise, an ill-configured email server or authentication methods might trigger unnecessary bounces.

Important Note - You should also look for other unusual behaviors like high unsubscribe or spam complaint rates.While some unsubscribes are typical and expected, consistent requests may indicate content issues. Spam complaints, however, are not tolerated, and your rate should be no higher than 0.1% (1 in 1,000 emails).

Adjust your email content & subject lines

If your emails read as “delivered” but show lower-than-expected opens and clicks, it’s time to workshop the email content.

Lookout for spam filters

First and foremost, “delivered” doesn’t mean “inbox.” Overusing certain spam words can easily trigger a spam filter and send your email to the corresponding folder. Not everyone checks their spam folder, which can easily be the culprit for your low recipient engagement.

Be direct (yet intriguing) with subject lines

A great offer or exciting announcement can easily be missed by an uninteresting or misleading subject line. It’s also the first place to look if readers aren’t opening your emails.

It’s necessary, to be honest when it comes to the email subject. Let your readers know what they’re getting into. If you have something exciting to share - tell them.

However, leave a little excitement for the primary email content so that readers have something of value to gain as a reward for their open.

Check out these tips for crafting perfect email subject lines.

Keep it concise

Your subscribers receive over 100 emails daily. It’s foolhardy to assume everyone has time to read a lengthy letter.

The email content is one area where you want to keep your writing short and sweet. Hit the key points:

For some topics, there are lots you’ll want to write about. Use that as the call-to-action to encourage interested readers to click through to your website to learn more or redeem an offer.

Regular sending drives recipient engagement

Your sending schedule matters just as much as your email content.

Strong engagement numbers will positively influence your email deliverability. When ISPs see subscribers enjoy your content, future emails will likely receive consistent inbox placement.

How do you get more engagement? Send more high-quality emails. Many companies stick to 2-3 emails per week, but every brand is ultimately unique.

Finding the sweet spot varies depending on your brand and the type of content you create. Send too little, and your recipient engagement will fall behind. People tend to forget about you if you’re not sending regular reminders.

Likewise, you don’t want to spam your readers’ inboxes. Too many emails can reduce the perceived value of each message. Your subscribers are likelier to skip over messages or even report them as spam if they’re particularly annoyed.

Master email deliverability for better email marketing ROI

To master email marketing, you must start by reliably reaching the inbox.

You can achieve this by taking control of your email deliverability – starting now.

Here’s a quick recap of what you need to do next:

Each of these tactics is critical in helping you keep your email bounce rate low and your campaign performance strong. The better you adhere to email marketing best practices, the stronger your sender reputation and email deliverability will be.

Don’t wait to start - take the first step and try ZeroBounce’s email verification tools. Our email verifier offers everything you need, including:

• 100 monthly email verifications - free
• 99% accuracy - money-back guarantee
• Identifies 30+ email types
• Helps you achieve an email bounce rate of 2% or lower

We also have a platform of tools designed to help you monitor your reputation and improve your email deliverability. Get access to those tools by signing up for your free account today.