What is the more secure alternative to the SMTP mail protocol? Explained by experts

Wondering what is the more secure alternative to the SMTP mail protocol? Learn about the best SMPT alternatives in our in-depth guide on email security.

Email protocol diagram, including SMTP servers.

Despite the meteoric rise of social media and messaging apps to the forefront of the internet, email’s importance hasn’t faded. The messages we exchange on Instagram, Facebook, or WhatsApp are less official and structured than the ones we send as private emails, which is especially important in more formal settings like the workplace.Another reason is email's stability and reliability—the foundational internet protocols that most email platforms are based on have changed very little from their inception in the early 1980s.The Simple Mail Transfer Protocol (SMTP) is chief among them because it governs how messages are transmitted between email servers. Unfortunately, SMPT wasn’t designed with built-in security. We use alternative email security protocols and other methods to send secure documents and email messages.In this article, you’ll discover:

What are the basics of email protocols?
How do we define SMTP?
What are different types of email security?
What is the more secure alternative to the SMTP mail protocol?

Upgrade your email securitySkiff Mail offers end-to-end encryption, protecting your inbox and sensitive information from unauthorized access

Email protocols explained

We use different custom email domains and email service providers, but we can easily send an email from a Gmail address to an Outlook account or vice versa. This is possible thanks to email protocols.An email protocol is a group of standardized rules defining how email data travels between email clients and servers. The result is a universal email sent to and received from any email platform or server. Without SMTP, someone using Gmail couldn’t send a message to a Yahoo mail user—or at least, not as effortlessly.Besides SMTP, the most widely used email protocols are:

POP3—Post Office Protocol 3
IMAP—Internet Message Access Protocol

Here’s a quick rundown of their basic functions:

Email protocol	Function
POP3	Transfers your email data from a server to a single device, letting you view emails on a computer or a smartphone
IMAP	Transfers your email data from a server to all of your devices, allowing you to read emails on multiple devices simultaneously

What is SMTP, and what does it do?

Your device uses the POP3 and IMAP protocols while retrieving email data from a server. SMTP is the set of rules that decides how that data will reach your email server in the first place by regulating how it is transferred between servers.Most people perceive the process of sending an email like this:

You write the email and click Send
It appears in the recipient’s inbox

This is what happens in practice:

You write the email and click Send
The email is transferred to your email server
The message travels from your server to the recipient’s email server via SMTP
The recipient’s email client downloads the message to their device
It appears in the recipient’s inbox

Thanks to today’s Internet speed, the process is almost instantaneous.Email communication wouldn’t be possible without SMTP, but that protocol doesn’t come with encryption or other security features. Solely relying on SMTP means your email correspondence is unprotected in transit from server to server and while resting on one of the servers. Additional measures have to be taken to safeguard your messages and attachments from unauthorized access.

Different types of email security—best SMTP alternatives

To ensure email services for businesses and individuals are secure, email clients provide additional security measures:

We’ll explain how all of them work to help you choose the best SMTP alternative for your emails.

Email security protocols

Like SMTP, email security protocols are sets of rules that ensure the functionality of global email exchange. Specifically, security protocols govern how your ESPs keep your emails anonymous, secure, and private. Most fall into one of two categories:

Type of protocol	Function	Example
At-rest protocol	Protects emails while on the sender’s or recipient’s email servers	Secure/Multipurpose Internet Mail Extensions (S/MIME)
In-transit protocol	Protects emails while en route between two servers	Transport Layer Security (TLS)

Most ESPs, like Gmail, implement both protocols, but only premium G-Suite users have access to S/MIME.Free users, who make up the majority, can only rely on TLS for email security. The same goes for Outlook users, who need a Microsoft 365 subscription to use the S/MIME protocol or any email encryption.

Private email servers

One of the ways to achieve email security is to set up a private email server. That way, you don’t have to rely on ESP’s email security measures. If you set up your private email servers correctly, you’re less vulnerable to hacker attacks, and no ESP can access the contents of your emails. In the past, Google has used email data for audience targeting in its digital advertising business, and a private server lets you avoid such misuse.Still, you only get the benefits of email servers with proper setup and constant maintenance, which rarely outweigh the cost. The process involves buying, setting up, and maintaining expensive server hardware and software. Even if you have the immense prerequisite knowledge for the job, it is time-consuming and costly.Running a private email server also means implementing every security measure yourself. In most cases, you won’t set up a better email security system than Google, Yahoo, or any large ESP. You can use hosting solutions to outsource the hardware management to someone else, but that still leaves you with a lot of work.

Password protection

Some email clients give you the option of protecting your emails with a password. If you only tell the password to your intended recipient, no one else can access the email. This security method is a step up from relying solely on your ESP’s security protocols, but it comes with its own set of issues.Not all email clients support password protection—Gmail does, for example, but Outlook doesn’t. Gmail’s Confidential Mode also involves the recipient reading the password from a smartphone, and relying on external devices isn’t ideal from a security perspective.Password protection is not an elegant solution because it requires manual work from the sender and the recipient—unlike secure email protocols or email encryption.

Email encryption

This security method turns an email into a coded message, ineligible to anyone except the intended recipient. ESPs use various encryption methods, each involving a complex algorithm that creates a cipher for your messages. The only way to decipher the message is to apply a decryption key, which (ideally) only the recipient has.Common email encryption happens on the server level—TLS, S/MIME, and other security protocols encrypt a message before it is sent from one email server to another. The email service providers implementing these protocols store copies of the decryption keys on their servers and can use them to access your data.This type of encryption can be broken if hackers gain unauthorized access to an email server, so the encryption is only as strong as the server's security.

Opt for top-notch email privacySkiff's E2E-encrypted email and storage ensure your emails are truly secure and owned by you

End-to-end encryption—the best solution

Like email encryption in general, end-to-end encryption (E2EE) involves transforming regular messages into cyphers unreadable to anyone but the authorized recipient. E2EE follows the same principle but goes further by ensuring encryption security from both endpoints.While standard encryption used by ESP’s security protocols involves server or network-based encryption, E2EE encryption protects the message at the device level.By the time a message has been uploaded to a server, E2EE has already made it unintelligible to anyone but the recipient—including your ESP or hackers who break through the server's security. Such unauthorized parties would see the same unintelligible message as everyone else without the means to decipher it.E2EE is the best SMTP security alternative because:

It protects your anonymity and privacy—Your ESP can’t read your messages, so they can’t be used for ad targeting or any other activity without your knowledge
It’s more reliable than standard email encryption—Standard email encryption relies on your ESP’s servers, putting your data in the control of your email client and the company behind it. With E2EE, you retain complete control of your data

Skiff is the ultimate E2EE email client

Mainstream email clients, like those operated by Google, Microsoft, and Yahoo, don’t provide E2EE protection. Their encryption methods are server-based, leaving your emails vulnerable to interception by man-in-the-middle (MITM) and other cyberattacks.

Skiff is an excellent choice for E2EE-protected email. The platform provides all the web-based productivity tools you need, with optional Android and iPhone apps for accessing your work on the go. Register for a free account and gain access to:

Skiff Mail—an E2EE-secured email client
Skiff Drive—an encrypted cloud storage solution for private files
Skiff Calendar—a secure scheduling app
Skiff Pages—a browser-based workspace with collaboration features

Most ESPs make you choose between email privacy and a modern, easy-to-use UI. Skiff combines the well-designed interface of popular ESPs with the ultimate encryption-based security across all Skiff tools.The transition is smooth, so you can easily migrate from your previous email service provider by importing all email data into Skiff Mail. A free account gets you 10 GB of storage, an email search function, four aliases, and signature and auto-reply options, but you can move up to the Essential, Pro, or Business tiers at any time and get additional features—including up to 1 TB of storage and custom email domains.

Take control of your online data with Skiff

Thanks to device-level encryption, no one can access your emails apart from their recipients—including Skiff. The platform also supports native web3 integration, allowing you to connect with your favorite crypto wallet and ensure any communication related to your online transactions stays private.

Signing up for a free Skiff account is easy. It takes three simple steps: