---
title: "A Comprehensive Email Security Checklist For Any Business Domain | DuoCircle"
description: "No standard business in today’s world operates without an email server. Most business communication takes place through emails."
image: "https://www.duocircle.com/images/og-default.png"
canonical: "https://www.duocircle.com/blog/email-security/comprehensive-email-security-checklist-for-any-business-domain/"
---

Quick Answer

An email security checklist for a business domain covers ten controls. Mail access restriction: limit who can read company email and from which networks. Mail monitoring: log inbound and outbound traffic so leaks and abuse are visible. Email spoofing protection: deploy authentication so attackers can't send as your domain. SPF: publish a record listing authorized sending IPs and include statements. DKIM: sign outbound mail with a private key and publish the public key in DNS so receivers can verify integrity. DMARC: tie SPF and DKIM together with a policy (none, quarantine, reject) and aggregate reporting; without DMARC, SPF and DKIM are advisory. Spam filtering: a fast filter at the gateway so manual triage doesn't consume employee time or expose them to malicious content. Attachment restrictions: block dangerous extensions (.exe, .bat, .vbs, .jar, .swf, .cab) at the gateway. Malicious URL protection: scan and rewrite links since one in 61 emails contains a malicious URL. Throttling policy: cap how many messages each user can send, receive, and forward per day so a compromised account has bounded blast radius. Add employee training on top, because the technical controls only work if users don't actively defeat them.

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![Email Security](https://media.mailhop.org/duocircle/images/2021/05/spf-record-6241.jpg) 

_No standard business in today’s world operates without an email server_. Most business communication takes place through emails. It also means that a lot of sensitive, personally identifiable information (PII) remains in such organizations’ mailboxes. But a single cyberattack or **security vulnerability** can invite trouble not just in the form of business disruption but also as a risk of [identity theft](/phishing-protection/recognizing-online-identity-thefts-and-how-enterprises-can-ensure-identity-theft-protection-for-their-employees/), extortion, or financial loss for all stakeholders, including employees, partners, and the most crucial part of any business, the customers.

_Ensuring customer **data security** should always be the topmost priority of businesses_. As such, enterprises should be diligent in choosing [email security solutions](/) for their businesses. **Email security** ensures that only authorized sources can send emails to an organization, and only approved entities can access them. Strictly following a comprehensive email security checklist that includes all critical aspects of email security can help ensure **protection against threats** such as phishing and ransomware for a business domain.

## What Happens To A Business Without Email Security?

There is no end to the innovative list of cyberattacks that can arise if a business does not maintain a secure email server. _A business email domain might receive more spam emails than pertinent ones_. **Phishing emails** often come embedded with malicious attachments and links to fraudulent web pages that can steal users’ credentials. Spam emails are another major threat to organizations because they can cause wastage of resources and impact productivity. [Business email compromise](/email-security/the-newest-business-email-compromise-request-gift-cards/) (BEC) is a particular category of **phishing scams** that can make organizations transfer vast sums of money to fake service providers and even trick customers.

The above graph shows that BEC scams hit the US, the UK, and Australia the worst in 2019, and the picture doesn’t look too good for other nations either. _A business without email security is like a sinking ship in a turbulent tide_. Therefore, organizations across the globe need to use [anti-phishing services](/email/phishing-protection) and other **robust email security** tools.

[![Email Security](https://media.mailhop.org/duocircle/images/2021/05/spf-record-check-4529.jpg)](https://media.mailhop.org/duocircle/images/2021/05/spf-record-check-4529.jpg)

## What Should An Email Security Checklist Include?

Choosing _the right [email security service](/) provider for the business is imperative to protect it from malicious cyber scams_. However, finding a solution with maximum security features is difficult without a clear idea of the organization’s security needs. The following is a comprehensive email security checklist containing all critical security aspects for a business domain:

### Mail Access Restriction

With this feature, the administrator can regulate who can access the organization’s emails. _It enables restricting outsiders or even insiders on unsafe networks from accessing confidential digital information of the business_.

### Mail Monitoring

Having a mail monitoring manager supervise all messages sent and received within and outside the organizational network ensures that no employee in possession of sensitive official data can misuse or leak it. _Mail monitors regulate online interactions without notifying employees about it_.

### Protection Against Email Spoofing

[Email Spoofing](/phishing-protection/how-to-prevent-phishing-and-spoofing/) attacks can tarnish an enterprise’s goodwill, and therefore a good _email security vendor must ensure safety against such attacks_. It prevents scammers from sending out emails to clients or employees impersonating the enterprise email domain.

### Enabling SPF

An [email security solution](/) must come with Sender Policy Framework (SPF) to ensure **email spoofing protection**. [SPF-enabled](/email/spf-record-check) servers only accept emails from the permitted list of server IP addresses.

### Enabling DKIM

_The Domain Keys Identified Mail (DKIM) is a great way to protect against spear phishing, spoofing, and other impersonation attacks_. Enabling DKIM ensures that only verified or [DKIM-encrypted emails](/resources/what-is-dkim) get accepted. DKIM lets businesses add an **encrypted digital signature** to each outgoing email. It ensures that no intermediaries can meddle with the message. It gets decrypted only with the DKIM domain key of the recipients’ email server.

### Enabling DMARC

Once the SPF and DKIM are enabled, businesses should look for enabling Domain-based Message Authentication, Reporting, and Conformance (DMARC). [DMARC](/email/dmarc) creates an additional layer of **email security** that restricts adversaries from impersonating a business email domain and helps verify the authenticity of sender domains.

### Spam Filtering

_A quick and robust [spam filtering](/email/spam-filtering) system makes an email security solution more adaptable for businesses_. The reason is that manual detection of spam emails takes up a lot of productive time and poses **security risks** for unsuspecting employees.

[![spam filtering](https://media.mailhop.org/duocircle/images/2021/05/spf-record-generator-2891.jpg)](https://media.mailhop.org/duocircle/images/2021/05/spf-record-generator-2891.jpg)

### Attachment Restrictions

Having the administrator regulate the types of permissible email attachment extensions is an effective **email security solution**. _It ensures that employees neither receive nor send suspicious attachments_ like .cab, .exe, .bat, .jar, .vbs, .swf, etc.

### Protection Against Malicious URL

A vital aspect of [phishing protection](/email/phishing-protection) is ensuring security from malicious links. Since one in every [61 emails](https://www.zdnet.com/article/phishing-alert-one-in-61-emails-in-your-inbox-now-contains-a-malicious-link/) contains malicious URLs, the auto-detection and deletion of such emails with suspicious links are preferred in an **email security solution** for businesses.

### Throttling Policy

Having a throttling policy in place ensures that the adversaries can only do so much damage to the business. [Email forwarding](/email/email-forwarding) is one notorious act the adversaries engage in after compromising a business domain. _A throttling policy restricts the number of emails each employee or sender can receive and send in a day_, along with an upper limit for email forwarding.

### Training Employees

Email security measures are incomplete without spending time and resources on spreading cyber [awareness among employees](/phishing-awareness-training). The employees need to be trained in identifying phishing emails and encouraged to maintain **cyber hygiene** while working on the enterprise network.

## Final Words

_Business email security is an essential parameter for ensuring the overall cyber wellness of the organization_. Hence, the email security checklist presented above must be strictly adhered to by any organization based on its security needs. Apart from investing in cybersecurity services, business domains should make strategic choices in selecting email vendors because outbound SMTP, spam filtering, [phishing protection](/email/phishing-protection), and other such security features could come free-of-cost with some vendors. A business domain must first analyze its needs and then go for an [email security service](/) accordingly.

![Brad Slavin](https://media.mailhop.org/dmarcreport/images/team/brad-slavin.jpg) 

Brad Slavin 

General Manager

General Manager at DuoCircle. Product strategy and commercial lead across the email security portfolio.

## Secure your email infrastructure

Protect, authenticate, and deliver. Contact our team to find the right solution.

[Contact Sales](/contact/) [Explore Products](/products/) 

## Related Articles

[  Email Security 8m  BIMI in 2026: What the Certificate Authority Does, and What Your DMARC Tool Does  May 5, 2026 ](/blog/bimi-2026-what-the-ca-does-what-your-dmarc-tool-does/)[  Email Security 8m  Designing A Custom Dkim Architecture For High-Volume Email Senders  Apr 28, 2026 ](/blog/designing-custom-dkim-architecture-for-high-volume-email-senders/)[  Email Security 12m  DMARC, SPF, and DKIM in 2026: Why Email Authentication Is Now a Regulatory Requirement, Not Just a Best Practice  Apr 29, 2026 ](/blog/dmarc-spf-dkim-2026-email-authentication-regulatory-requirement-best-practice/)[  Email Security 5m  Email Monitoring Tools: A Complete Guide to Protecting Your Email Ecosystem  May 7, 2026 ](/blog/email-monitoring-tools-guide-protecting-your-email-ecosystem-security/)

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