Security & Privacy·Standings

Email Spam Filtering Software

Email spam filters help keep unwanted, phishing, and malware-laden messages out of inboxes. Compare supported platforms and whether a free plan or trial is available.

This board shows a signal score out of 10 based on published information. Look for marks showing a public API, open-source code, and a free tier, then check pricing and platform labels.

  • 11 platforms
  • 1 with a free tier
  • Checked 22 Oct 2026
  1. 1
    C
    Cloudflarecloudflare.com

    Internet platform offers DNS, DDoS protection, CDN, SSL, web application firewall, and serverless computing.

    5.8 APIOpenFree Free tier · from $20/mo
  2. 2
    H3
    Hornetsecurity 365 Total Protectionhornetsecurity.com

    Microsoft 365 suite filters spam, malware, phishing, and BEC, with encryption, archiving, and backup.

    5.3 APIOpenFree —
  3. 3
    SG
    SpamTitan Gatewayspamtitan.com

    Anti-spam gateway filters unwanted email and malware, with on-premises deployment and mail-flow controls.

    5.3 APIOpenFree —
  4. 4
    MD
    Microsoft Defender for Office 365Microsoft

    Email and collaboration protection helps block phishing, business email compromise, and malware in Microsoft apps.

    5.3 APIOpenFree —
  5. 5
    SE
    Sophos EmailSophos

    Email security blocks phishing, spam, and malware, with links to Microsoft 365 plus Google Workspace.

    5.2 APIOpenFree —
  6. 6
    CP
    Check Point Harmony Email & CollaborationCheck Point

    The product aims to stop sophisticated email threats before they reach inboxes, protecting users and AI agents across Microsoft 365, Google Workspace and…

    5.1 APIOpenFree —
  7. 7
    AS
    Abnormal Securityabnormal.ai

    Email security uses behavior patterns to find business email compromise and vendor scams.

    4.9 APIOpenFree —
  8. 8
    DE
    Darktrace / EMAILdarktrace.com

    Behavior-based email security detects phishing and impersonation, then tags or quarantines suspicious messages.

    4.9 APIOpenFree —
  9. 9
    ME
    Mimecast Email Securitymimecast.com

    Email and collaboration security uses AI and relationship patterns to detect fraud, malware, and credential theft.

    4.8 APIOpenFree —
  10. 10
    TE
    Trellix Email SecurityTrellix

    Cloud, gateway, or API protection detects email campaigns and offers DLP and message removal.

    4.7 APIOpenFree —
  11. 11
    TV
    Trend Vision OneTrend Micro

    Security platform; the supplied details do not specify email filtering features.

    3.9 APIOpenFree —

Places #1, #2, #3, #4, #5 on this board are open to sponsors. Take #1 · Other ways to advertise

How to choose

What platforms can it run on?

Choose based on the platform your mail setup can use. The board indicates which products provide web access, an API, or self-hosting.

An API lets another service exchange messages or results with the filter. Self-hosting means running the software on infrastructure you manage.

Where can I find pricing?

Pricing may be listed publicly or provided on request. SpamTitan Gateway starts at $1.95 per user monthly when billed annually.

Abnormal Security, Darktrace / EMAIL, Hornetsecurity 365 Total Protection, and Mimecast Email Security provide pricing on request.

Are free plans or trials available?

Cloudflare is the only listed product with a free plan. A free trial is marked separately, so check both labels before choosing.

Darktrace / EMAIL and Mimecast Email Security offer 30-day trials; Hornetsecurity 365 Total Protection offers a 14-day trial. Check Point Harmony Email & Collaboration, Microsoft Defender for Office 365, and Sophos Email also mark free trials.

Which email threats are covered?

Look for stated coverage that matches your risks. Sophos Email covers phishing, business email compromise, spam, and malware delivered by email.

Trellix Email Security covers inbound and outbound email, with threat detection, actionable alerts, and email claw-back capabilities.

Is open-source code important?

Use the open-source mark to check whether a product publishes code you can inspect or change. The board separately indicates public API access and free tiers.

Questions

Which email spam filters have a free plan?

Cloudflare is marked as having a free plan.

Are free trials available for email spam filters?

Trials are marked for Check Point Harmony Email & Collaboration, Darktrace / EMAIL, Hornetsecurity 365 Total Protection, Microsoft Defender for Office 365, Mimecast Email Security, and Sophos Email; trial durations differ.

How much does SpamTitan Gateway cost?

SpamTitan Gateway starts at $1.95 per user per month with annual billing.

Which email security tool protects both incoming and outgoing mail?

Trellix Email Security states that it protects inbound and outbound email and supports email claw-back capabilities.

Which email filters have an API?

The platform labels identify API support. Check those labels alongside web or self-hosted options to match your mail workflow.

Some top positions on this board can be paid placements, standing where they were sold. The facts on each platform are not for sale. How we rank · Disclosure