Why Do I Need an Email Digital Certificate?

1 Star2 Stars3 Stars4 Stars5 Stars (3 votes, average: 18.67 out of 5)

As a respected and reputable reseller of all types of digital certificates, we often find ourselves facing questions about what an email digital certificate is and why it’s useful. As such, we’d like to take a few moments to explain exactly what it is, how it works and, most importantly, why you need one to protect your email.

What is an Email Digital Certificate?

An email digital certificate, sometimes called an email digital signature certificate or an S/MIME certificate, is an X.509 digital certificate that’s used to secure email data at rest. The reason why many major organizations globally choose to use these certificates is because emails are bounced around from server to server and across the internet. This leaves them vulnerable to man-in-the-middle (MitM) attacks without any type of protective measure in place.

Another reason is that they use them to meet regulatory compliance concerns that are outlined by:

  • the Healthcare Insurance Portability and Accountability Act (HIPAA),
  • the General Data Protection Regulation (GDPR),
  • the Payment Card Industry (PCI) standards, and
  • the U.S. Department of Defense’s Acquisition Regulation Systems (DFARS).

These email digital signature certificates are issued by different certificate authorities, or CAs, and can be used with most major email clients. For example, we get people coming to us who are looking to buy an Outlook digital certificate, but what they’re really looking for is one of these email certificates. They just happen to be wanting to use it on their Outlook email client.

Here at CheapSSLsecurity.com, we borrow from one of our certificate authority partners, Comodo CA, and refer to them as personal authentication certificates, or PACs. That’s because they help you authenticate yourself to users in addition to providing end-to-end encryption of your email data.

Purchase an Email Digital Certificate & Save Up to 74%!

We offer the best discount on all types of email signing certificates with prices starting as low as $9.98 per year.

Shop Now

How Does an Email Digital Signature Certificate Work?

If you’re looking to get a breakdown of how an email certificate works, you’ve come to the right place. In a nutshell, an email signature certificate performs two main functions:

  • It authenticates you so your email recipients know that you are who you say you are, and
  • It ensures the integrity of your email message and attachments by encrypting your plaintext email information before you hit “send.” This way, only your intended recipient can open it.

It does this through the use of public key encryption and hashing (which is used to create a digital signature).

Graphic: Private key encryption


This is different from an SSL/TLS certificate, which is used to protect data in transit by creating a secure, encrypted connection. You can use an SSL/TLS certificate to secure an email server but not the contents of the emails themselves. This is where an email digital signature certificate comes in handy.

When you use an email signing certificate from a reputable CA, it means that that CA is including their digital signature whenever you send an email. This helps to assure email clients and users by backing up your claim that you’re you.

Like SSL/TLS certificates, email digital certificates also have validation levels. But instead of the domain validation, organization validation, and extended validation of SSL/TLS, you instead have:

  • Email validation — This process verifies your email address and domain.
  • Individual validation — This process requires government-issued identification that verifies you’re you. It also requires a valid company email address. This will result in the issuance of a certificate that has your name on it.
  • Organization validation — This last one is the most rigorous of the three processes. That’s because the CA is trying to verify that your organization is legitimate. This involves a verification phone call, verification of your organization’s email domain, etc. This will result in the issuance of a certificate that has your organization’s name on it.

So, Why Do I Need This Type of Certificate?

If you’re still not sure why you need an email digital signature certificate, let’s break it down into a few key reasons:

  • To digitally sign your emails to assert your identity. This way, your email recipients can verify that you sent the email and not an imposter.
  • To encrypt your email messages and attachments to ensure they remain unaltered and secure.
  • To comply with industry and regulatory compliance requirements and recommendations.
  • To make your email recipients feel more confident and comfortable interacting with your emails and any attachments.

We hope this article has helped you recognize the importance and value of using an email digital certificate to secure your messages.