Email security for small business: 10 proven best practices for protection

In fact, up to 43% of all cyberattacks now target small businesses, with BEC attacks representing one of the most financially devastating threats. According to Abnormal Security, attackers are using advanced social engineering techniques to infiltrate companies by exploiting human trust and email-based workflows. These sophisticated scams are often carried out via malicious emails, phishing attacks, and impersonation tactics. In this article, we’ll walk you through 10 actionable best practices to strengthen your small business email security, reduce risk exposure, and increase employee security awareness, while keeping operations running smoothly.

What is email security for business?

Email security for small businesses involves protecting corporate email systems from cyber threats like phishing, malicious attachments, and data breaches. It includes both technical solutions, like encryption, filters, and multi-factor authentication, as well as human-centric strategies—security awareness training and policy enforcement.

Compared to larger enterprises, small businesses face unique challenges. With fewer resources and often a lack of dedicated IT teams, these organizations must rely on efficient, scalable security solutions. That’s why establishing a strong email protection framework is critical to safeguard sensitive data and business continuity.

What is Business Email Compromise (BEC)?

BEC is a type of cybercrime that involves impersonating a trusted business contact, such as a CEO or supplier, to trick employees into transferring money or sensitive information. These scams are often the result of careful research and social engineering to create a convincing ruse.

According to the FBI, BEC fraud has cost companies over $26 billion globally since 2016, and the threat continues to grow. Small businesses are particularly vulnerable, as they may not have the resources or expertise to detect and prevent these attacks.

One example of a BEC scam involved the director of Puerto Rico’s Industrial Development Company, Ruben Rivera, who mistakenly made a transaction of $2.6 million to a fake bank account. In another case, Ubiquiti Networks Inc. the San Jose-based manufacturer of high-performance networking technologies, fell victim to a BEC attack that resulted in a loss of $46.7 million.

As the use of email continues to be an essential aspect of business communication, companies must remain vigilant and take proactive measures to defend against the threat of BEC. It applies to all kinds of companies: Email security for small businesses is as fundamental as for big corporations.

Why is email security important?

Email has become an integral part of our digital lives, functioning almost like a virtual ID card that allows us to identify ourselves online and sign up for services. As one of the most popular methods of online communication, our emails contain sensitive information about us. If malicious parties gain access, they can take over the user’s other online accounts, steal their confidential data, and pose serious financial and reputational threats to that user. This is why email is so often targeted by cybercriminals; according to Verizon’s Data Breach Investigations Report, 94% of malware is delivered via email. Given the risks and the frequency of email malware attacks, ensuring email security is crucial, especially in business environments.

Phishing is the number one email security threat

Phishing is a type of digital scam that is especially common in emails. It’s a form of social engineering where a hacker tries to deceive an employee into believing the email is coming from a credible source. Such emails usually have a CTA: it’s like a form of marketing. Except that phishing CTAs usually involve clicking on a malicious link or revealing sensitive company data to outsiders.

Well, just like any other marketer, hackers employ creative techniques to improve the conversion rates of their scams. The more deceitful the email, the higher the conversion rate. That’s why phishing emails can be difficult to spot at times. This highlights the importance of email security for business. Examples of phishing emails include:

• Account verification scam. You may receive a phishing email that looks something like this: “Due to a recent security threat, we would like to ask you to verify your account by signing in through the link below. Failing to do so will result in the permanent deactivation of your account.”

• Fake invoice scam. Hackers may send out emails saying, “We still haven’t received your payment for our services. Please use the link below to complete the transaction.”

• Spear phishing. This is a more advanced and tailored form of phishing that requires hackers to do some research on your company. For instance, an employee may receive an email that looks like it’s coming from a specific coworker, instructing them to visit a website or disclose information.

Best practices for business email security

Falling for phishing scams can expose your company to data breaches and malware. Taking steps to appropriately ensure the security of your email will help protect your business from phishing and other forms of cybercrime:

1. Conduct phishing awareness training

Emails usually get breached through employee negligence and lack of knowledge. So the first way to increase email cybersecurity is to raise awareness about the main threat: phishing. All employees should receive in-depth training on email threat protection — recognizing and avoiding attempted phishing schemes. The main points to cover here are:

• Becoming familiar with the main phishing schemes

• Being suspicious about unusual requests

• Never click on random links received through email

Once employees are familiar with these precautions, your company’s susceptibility to phishing emails will significantly decrease and your business email security will improve in general.

2. Deploy data loss prevention (DLP) tools

Modern data loss prevention (DLP) tools monitor, detect, and block the transmission of sensitive information. For example, Fortinet FortiMail prevents unauthorized data sharing via outbound emails and scans for compliance violations. These tools help prevent unintentional leaks, whether caused by human error or malware.

By integrating DLP with your email systems, you reduce the risk of compliance violations and reputational damage, ensuring business email protection without slowing down workflows.

3. Enable multi-factor authentication

You can make your account safer from hackers by connecting your smartphone to your email. Even if the passwords to your email accounts are leaked, no outsiders will be able to access them without having access to the device it’s connected to. All vital business accounts, not just email accounts, should have multi-factor authentication enabled.

4. Avoid using email when on public Wi-Fi

Public Wi-Fi poses massive risks to email security. If it’s unencrypted (which it often is), anybody can connect to the same network. You never know when a hacker will be that someone.

If a hacker intercepts your connection with unencrypted public Wi-Fi and catches you logging into your email, they can steal your email password. It’s best to steer clear of public Wi-Fi altogether, but if connecting to it is necessary, never transmit important data while on it.

5. Avoid using business emails for private purposes and vice versa

Most office jobs these days come with an email address. Some people get the temptation to use the new email address for all sign-ins. Need to sign up for a new streaming service? Well, why not use your brand-new business email for that? Everybody else does it, anyway, right?

At first, it might sound like a great idea. Yet using your enterprise email for private purposes and vice versa could cause significant security concerns for you as an individual and the company.

First, using a company email for your personal online activities allows for easier and simpler profiling. Consequently, that could lead to spear-phishing — a targeted phishing campaign or other targeted cyberattacks.

6. Encrypt company email

Encrypting company email using special email security software is a great way to steer hackers away. Encryption ensures that the only people able to view the emails are the sender and recipient. If a hacker intercepts an employee’s Wi-Fi connection or email account, they will not see any sensitive data.

7. Set up email security protocols

Email security protocols are immensely important because they provide an extra layer of security to your digital communications. The protocols are designed to ensure the safety of your communications as they pass through webmail services over the internet. Without the aid of email security protocols, bad actors can intercept communication in a relatively easy manner. Please familiarize yourself with the three most popular email security protocols and enable them to ensure secure communications.

• Transport Layer Security (TLS): TLS — the successor of SSL, Secure Sockets Layer, protocol — encrypts email messages when they travel between mail servers. It makes it much harder for hackers to intercept the communication and eavesdrop.

• Domain Keys Identified Mail (DKIM): DKIM adds a digital signature to emails, allowing receiving mail servers to verify the authenticity of the messages. It protects the company servers from phishing attempts and tampering emails.

• Sender Policy Framework (SPF): SPF allows domain owners to create a list of mail servers that are authorized to send emails on behalf of their domain. When a company server receives the message, it can authenticate the sender by comparing its email address with the SPF records.

8. Improve endpoint security

To further fortify your security stance, take action to improve your endpoint security. Often the easiest and most effective way to boost endpoint security is by implementing security tools for company-wide use.

Consider deploying a VPN like NordLayer — a tool that encrypts the internet connection and data transferred over your business network. Antivirus software is another tool that should be used on all business workstations to ensure a proactive defense.

9. Don’t change passwords too often

Password fatigue is a fact of life — today, the average user has about 100 passwords on their hands. Keeping track of all the passwords is a challenge.

The conventional wisdom regarding password security is that you should change your passwords every 90 days. While that might sound like a reasonable security practice, it could lead to simpler and easy-to-crack passwords being used.

If you know that your employees take password hygiene seriously and craft hard-to-guess passwords and that none of their passwords were ever leaked, then they should stick to the passwords they already use. If any password (no matter how strong it is) is leaked or breached — the change should be immediate.

10. Use strong passwords for email accounts

Strong passwords are the backbone of account safety. Yet businesses often fail to secure their emails with strong passwords. If your business is like this, you should know that the easier the password, the easier it is to hack, especially through brute-force attacks. Brute-force attacks are when hackers try to guess a password by flooding your account with thousands of attempts.

To protect your business email from such attacks, ensure everyone in your organization secures their passwords. Secure email passwords are:

• Long

• Complicated

• Contain different types of characters

• Unique (never reused from other accounts)

These points are crucial if you want to ensure the safety of your business. However, passwords that are difficult to hack are also difficult to remember. The last thing anyone would want is to secure their account so well that they couldn’t even access it themselves.

Luckily, the business password manager and the enterprise password manager by NordPass can come to the rescue. If all members of your company use it for their accounts, their emails will be safe, and they won’t need to scratch their heads trying to remember their passwords.

What is the best email platform for small businesses?

For small business email security, especially when marketing and communication overlap, choosing the right email marketing tools is key. Below are 5 top platforms that balance simplicity, affordability, and security into one convenient package—ideal for SMBs:

1. MailerLite

Recommended for advanced entry‑level users, MailerLite offers a drag‑and‑drop editor, segmentation, dynamic content blocks, and automation—all free up to 1,000 subscribers and 12,000 emails/month. It’s beginner-friendly and scalable as your small business grows.

2. Brevo (formerly Sendinblue)

Brevo provides an all‑in‑one marketing and sales platform with CRM features, goal-oriented automation, and contact limit flexibility. The free plan supports up to 100,000 contacts and 300 emails/day, making it budget-friendly for small teams.

3. Moosend

Moosend is ideal for small businesses looking for email marketing tools with strong automation, list segmentation, real-time reporting, and personalized email templates. The intuitive interface helps small teams scale efficiently.

4. Kit (formerly ConvertKit)

Kit is tailored for creators and small businesses needing automation and monetization built into their email campaigns. It supports unlimited emails, customizable landing pages, subscriber tagging, and automation sequences—generous even on the free tier.

5. Mailchimp

A long-established leader, Mailchimp remains a popular choice for growing businesses. With comprehensive integration options, analytics, and a familiar interface, it supports scaling users, though its free tier includes branding and limited automation capabilities.

Bottom line

Business email security is never a given. Even though platforms like Gmail or Outlook do their best to ensure the safety of their users, you can easily fall victim to hackers if you don’t actively protect your account. By following these ten email security best practices, the chances of getting your business emails hacked will be much slimmer because hackers will likely prefer more vulnerable prey.