Email Verification, Process, Who Uses It, Best Practice, a Guide to Email Validation

Email Address Verification is an important practice for businesses of all sizes. Validating emails generates many great benefits while preventing numerous penalties for marketing and operating your business.

Your mailing list is the lifeline of your digital marketing campaigns. But if your car regularly needs a tune-up to stay healthy, ever wondered what it might take to keep your mailing list healthy? It’s called email verification. No idea what that is? No problem That’s why we created this guide to help you understand more about email verification.

Email Verification

What is email verification? Email verification (also known as email validation) is the process of verifying whether an email address is active, inactive or fake. Verifying your mailing list, allows you to squeeze the most out of your marketing campaigns. More specifically, it allows you to reduce hard and soft bounce rates.

But do you need it and what’s the process? And do you need an email address? let’s dive in deeper to find out...

Why Have Email Verification?

Any digital business, whether it’s a blog or an e-commerce site, builds its marketing campaign centered around a good mailing list. Email marketing is one of the most successful marketing tools in digital business.

The Digital Marketing Association estimated email marketing to provide a whopping 4300% return on investment. That kind of return is next to impossible on most other mediums, whether online or offline. But the health and efficacy of an email marketing campaign depend majorly on the health of the mailing list, among other factors.

Marketing Sherpa estimates that email addresses degrade at a rate of 22% per annum. That means if you have a mailing list of 100,000 addresses, more than 20,000 of them will be invalid in a years’ time. At that rate, there’s a need for continuous update and sanity checks of the mailing list.

When a person changes his/her email address, they generally delete the old one. However, the mailing lists which the person has subscribed is not updated. This generally happens when someone is switching companies, or changing email service providers. For example, a person switches from a Yahoo mail account to Gmail.

Another example of the same incidence is when the person changes their email address within the same service provider. Similarly, changes in position can also be a reason for a change in email addresses. Many companies provide different email addresses for their C-level executives, which is different from email IDs of medium or entry level executives.

If not done, then your emails will start bouncing off those invalid addresses. High bounce rates and low open rates will send the wrong kind of message to your email service provider. If you haven’t noticed previously, your business has a sender reputation with the email service provider or email marketing service (e.g. MailChimp, SendInBlue, AWeber, Constant Contact, GetResponse, etc).

The sender reputation is to help the email marketing service keep its servers from being blocked by other email service providers like Google, Yahoo, Outlook and others. Based on the kind of drop out rates, spam reports and block reports a sender gets, the email service providers rate the senders.

If you’re using email marketing services, then it’s their servers that run the risk of being blacklist along with your business. As a result, the email marketing services also maintain a sender reputation profile based on various factors including bounce rates. High bounce rates mean that your marketing service will blacklist your business and you won’t be able to drive your campaigns any longer.

As a result, it holds serious implications for your business. That’s why verifying your email list regularly and especially before big campaigns are important.

Have an email list ready for email verification? Upload it now or integrate our API for real-time email validation.

Is Email Verification Necessary?

Email List Verification

Now, we understand that email verification has its uses and that it’s important. But you might be wondering if it's NECESSARY? The answer is YES and NO.

Well, there’s no official mandate or rules that bind you to email verification. It’s totally your choice whether you opt for it or not. In fact, when I first started an online business, many businesses don’t know enough about email verification and continue campaigns without it. These kinds of things tend to happen when you’re an entrepreneur trying to learn as you go. Fair to say with all the things new businesses need to get to grips with, understanding email verification is not likely to be the highest priority on their list.

However, as mailing lists grow, a sudden increase in bounce rates means some red flags will start to happen with your business as a sender reputation. If you notice falling email opens and a higher bounce rate, then you need to consult with an expert on the best way to correct the situation.

A consultant would likely ask you to conduct regular email verifications. If this is something new to you, then ask your consultant to explain what email verification is.

By adopting some new practices, you can see a real effect to your campaigns, they’ll start to perform better and engagement will increase. Your bounce rates should stabilize over time, your sender reputation will begin to improve and fall back in line to its former position.

So, if you ask if email verification is necessary? the answer is yes. That’s because of the use and credibility that it lends to the business. The return on investment is better and the brand reputation can be protected. Without it, your mailing list will steadily degrade.

How Does Email Verification Work?

Email list hygiene is a best practice that goes a long way in ensuring your messages are deliverable and won't be routed into the SPAM folder. Email verification services like ours can be used to conduct bulk validation of your mailing list. It can also be used for real-time verification of incoming email addresses by integrating an API to stop fake sign-ups. This ensures that bounce rates remain low and responses are as pure as possible.

In addition, with double opt-in procedures, real-time email validation allows businesses to keep their mailing list alive and healthy. These procedures need to be conducted at periodic intervals to ensure that the list remains fresh, otherwise, addresses will start becoming invalid. The key to email list hygiene is revalidating marketing lists every few months as email statuses do frequently change.

Email Verification Steps

The entire email verification process works in three easy steps. These are

  • Syntax and formatting check
  • Server confirmation
  • Mailbox validation.

These steps are conducted by email verification services as a primary tool to verify addresses.

Checking Email Syntax and Formatting

The first thing that email verification services check for is email syntax. Email syntax refers to the correct order in which email address should be created. The service will check the addresses against syntax of major and recognized email service providers. For example, a genuine Yahoo email address cannot start with a number. That’s one of the giveaways of a fake address.

Next, the service will check for email formatting. These are complex and intricate rules which, like the syntax rules, dictate which usernames are acceptable for email addresses. There are thousands and thousands of different permutations that need to be run. As a result, it’s not something that can be done manually. For example, the ‘@‘ sign is mandatory for any email address. Another one is that there cannot be special characters in an email address, and so on and so forth.

Server Confirmation

After the email address format and syntax are verified, the verification service will now move on to server confirmation. The service will check the DNS records for the domain name of the email addresses. If you have an email address "", the domain name is referred to "". The service will test the mail exchanger as part of this process to ensure that the email address is valid and able to accept emails.

A full email box will also cause bounces. As a result, the domain or server confirmation will help weed out those that are real but not available to take new mail. Since email marketing services cannot distinguish between fake email addresses and those who have their inbox full, it results in the same sender reputation degrade.

Mailbox Validation

The last and most important step of the verification is the mailbox validation. In this step, the mailbox is validated by service. They’ll try to contact the SMTP server and understand whether the particular mailbox exists and if it does, is it ready to accept emails.

Here, the verification service will ping the email address with an EHLO message and then wait for a response from the email server. When a server-response is received, it will confirm the email address and that it exists on the server and is active.

A genuine email verification service can do all this without sending a single mail due to the mechanics behind it. Generally, the email verification takes very little time, but overall it can depend on the size of the mailing list. The age of the mail servers, how busy the servers are and newer anti-spam systems can slow down the process.

Other services related to email verification include duplicate email address checking, role accounts checking, temporary email addresses, and spam trap removal.

However, these steps are not the only tools used. As mentioned previously, real-time verifications and double opt-in procedures also offer significant help in verifying addresses. The applicability of these tools is dictated by the need and situation of the business.

Real-time verification allows you to qualify the addresses at the time of the signup. However, it is only possible with API integration. As a result, if you aren’t a developer or do not have access to them, it might be difficult for you to accomplish.

Alternatively, double opt-in procedures are carried out immediately after the signup, but businesses might well be turning off subscribers by sending them confirmation emails.

Verify Email Addresses Without Sending a Return Email

As mentioned in the previous section, email verification is done in three steps. The last step is the most crucial step. Now, you might be thinking how is it possible to verify an address without sending a single email. This is mainly due to the mailbox validation process.

Here, the email verification service will ping the email address with an EHLO message. The EHLO is an Extended Hello message which is sent by one email server to another when it intends to connect itself with that server. This is done by SMTP servers in the normal course of sending an email message (applicable for only those using SMTP servers). But instead of sending an entire message, during the verification process only the EHLO is sent.

Once the verification service receives a reply, it conclusively decides that the address is valid. This allows the verification service to verify the email server without actually sending a mail. But of course, all this is dictated to by the service sending out and requesting the verification service and is not decided by the end user. i.e. the end user must send a response email if the service has demanded it in order to verify.

From an end user perspective then, they’re effectively being led down a path that is designed precisely TO verify their email address. Therefore, if the process requirements are not met then the ‘Golden Handshake’ does not occur. This is not possible without an email address being confirmed by the user.

What's Your Email Hygiene Rated? An average email list contains 30-40% invalid email addresses, which can greatly hurt your bounce rates. Many email providers will suspend service if they detect a bounce rates greater than 15%.

Who Uses Email Verification?

An email verification service is for all those who use a mailing list and those looking to gain sign up’s through email. This may include any online business, including bloggers, e-commerce sites, digital marketers, social influences, content creators, etc.

It allows them to gain maximum return from their campaigns and at the same time retain their brand value by keeping low bounce rates and high open rates.

Email Verification Best Practice

Not all invalid addresses are intentional. In fact, mistyped email addresses are a commonplace incident. These addresses represent the portion of your target demographic that wants to receive emails from you. But due to ‘typos’, they’re excluded from the mailing list.

Similarly, it might also be possible that the owner of the mistyped address does not want marketing emails. In which case, he or she would have marked the mail as spam, which would ultimately hurt your brand.

As a result, the only way to be sure that the owner of the address wants to receive your email is to send a confirmation email. The confirmation mail will have a unique URL which will allow the owner of the email address to verify that he or she indeed wishes to receive further communication from the brand. This process is also known as double opt-in.

In addition to helping you qualify your subscribers, it also allows the business to sift through malicious users who sign up with third-party email addresses or stolen email addresses.

Email Verification Message Examples

In order to help you understand how double opt-in procedures work, here’s an example of an email verification message.

Hi Mr. X,

We hope this finds you well!

Thank you for signing up with our service! Before we move on to the good stuff, there’s just one more step for you to take.

Click on this link below to confirm your subscription and we’ll take it from there -

*Insert email validation link here*

We hope to see you on the other side,

Thanks and regards,

Mr. Y,

ABC Corporation.


Email Verification is a pretty simple concept to understand overall and one that can greatly benefit your company's ability to land in the inbox of your clients. It's also a great way to prevent fake accounts and limit abusive user behavior. Most importantly, it will allow email marketing and other correspondence to directly reach your users without hitting the spam folder by maintaining a healthy sender score reputation.

To accomplish this, it's best to engage the help of a professional email verification service. At IPQS we specialize in email verification for a range of customers across many different industries. If you need to discuss your requirements with us then simply contact us now and we’ll be happy to help.

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