What does anti-phishing software do?

Anti-phishing software evaluates messages and related signals for signs of credential theft, impersonation, malicious links, malware, or other deceptive behavior. The exact evidence and action depend on where the product connects and which controls are enabled.

Which anti-phishing software is best for Microsoft 365?

Start by measuring Microsoft Defender for Office 365 with the appropriate license and recommended policies. Add a dedicated product only when a controlled test demonstrates a material detection, investigation, response, reporting, or operational gap. The best choice is the one that closes that documented gap with acceptable false positives and workload.

Which anti-phishing software is best for Google Workspace?

Start with Gmail's advanced phishing, malware, spoofing, and authentication controls. Compare a dedicated product against that configured baseline using the same messages and response tasks. A feature list alone cannot show whether the additional layer improves your tenant's outcome.

Do I need a third-party email security product?

Not necessarily. Native controls may meet the requirement when they are licensed, configured, monitored, and tested well. A third-party product is easier to justify when you have evidence of a specific gap and a trial shows that the added product closes it without unacceptable cost or complexity.

Does DMARC stop phishing?

No. DMARC can reduce direct spoofing of a protected domain when it is correctly deployed and enforced by receivers. It does not judge message content and does not stop every lookalike domain, display-name impersonation, malicious link, attachment, or compromised-account attack.

How should a business test anti-phishing software?

Use authorized simulations and a controlled set of known-good messages. Give each product the same impersonation, link, attachment, and authentication scenarios. Record detection point, user exposure, remediation time, false positives, investigation evidence, rollback steps, administrator effort, and the exact configuration used.

Anti-Phishing Software for Business: How to Compare Email Protection Tools

The best anti-phishing software is the option that covers the attack path your mail platform leaves exposed without creating an operating model your team cannot support. Start with Microsoft Defender for Office 365 if you run Microsoft 365, or Gmail's native controls if you run Google Workspace. Then compare dedicated tools against a documented gap. Proofpoint and Cloudflare offer gateway or cloud deployment choices; Abnormal centers on API-connected behavioral detection. Test the shortlist in your own tenant before buying.

Quick takeaways

Start with the controls included in your mail platform, then document what they miss or what your team cannot operate well.
Compare deployment before feature counts. Gateway, API, journaling, and native controls see messages at different points and create different mail-flow dependencies.
Treat every "best fit" below as a shortlist recommendation, not a measured ranking. Vendor documentation cannot replace a tenant-specific trial.
Test detection, false positives, remediation time, investigation evidence, and administrator workload with the same scenarios for every finalist.
Use DMARC beside inbound protection to reduce direct domain spoofing. DMARC does not judge whether a message or link is trustworthy.

Who this comparison is for

This guide is for internal IT and security teams, MSPs, and technical buyers comparing phishing protection for Microsoft 365 or Google Workspace. It focuses on inbound business email. It does not compare employee training platforms, browser isolation, endpoint protection, or incident-response retainers.

If you are still defining the threat, read what phishing is and how common variants work. Buyers dealing with executive or supplier impersonation should also review email impersonation controls.

How the options were evaluated

The criteria were set before looking at vendor evidence:

Deployment fit: Where the product connects, when it evaluates a message, and whether it changes mail flow.
Protection scope: Which phishing and impersonation controls the vendor currently documents.
Operating model: What administrators must configure, review, remediate, and explain to users or clients.
Proof required: What a buyer should reproduce in a controlled trial instead of accepting as a marketing claim.

This is a deliberately bounded shortlist, not a market-wide ranking. It includes the native controls in Microsoft 365 and Google Workspace, two products with documented gateway or cloud deployment choices, and one API-connected behavioral product. That range lets you compare operating models. It does not establish a universal top five.

Start with the protection category, not the vendor list

Native mail-suite controls are the logical baseline because they are already connected to the platform. A dedicated product becomes easier to justify when testing reveals a specific coverage, investigation, response, reporting, or multi-tenant operations gap.

An inline gateway evaluates mail in the delivery path. That position can support pre-delivery action, but it also makes routing and continuity part of the design. An API-connected product integrates with a cloud mailbox without becoming the MX destination, although detection and remediation timing depend on the integration. Journaling or BCC models receive a copy, which changes what they can do to the original message. Mixed deployments combine these patterns.

The deployment label alone does not predict detection quality. It tells you what to test.

Microsoft Defender for Office 365

Editorial best fit: Microsoft 365 teams that want to establish or improve the native baseline before adding another control plane.
Documented evidence: Microsoft's current anti-phishing documentation describes anti-spoofing and anti-impersonation protection. The default policy applies broadly, while custom policies can target users, groups, or domains. Microsoft recommends its Standard or Strict preset security policies.
Tradeoff to examine: A native product can simplify platform integration, but the result still depends on licensing, policy design, exceptions, alert handling, and the team's ability to investigate incidents.
Verify before buying: Confirm the exact license and preset policy coverage, test impersonation cases relevant to your organization, record false positives, and measure the steps required to investigate and recover a message.

Do not buy an overlapping product until you can name the gap it is meant to close.

Google Workspace Gmail protections

Editorial best fit: Google Workspace teams that need to harden and consistently operate Gmail's included safety controls before adding a separate product.
Documented evidence: Google's advanced phishing and malware protection documentation covers administrator actions for suspicious messages and settings for links, external images, attachments, spoofing, and authentication. Settings can be tailored by organizational unit.
Tradeoff to examine: Native settings reduce integration work, but distributed organizational-unit policies and exceptions can make it harder to understand the effective configuration.
Verify before buying: Inventory current settings and exceptions, test similar-domain and employee-name spoofing scenarios, and confirm how administrators find, investigate, and remediate messages across affected users.

The useful comparison is not "Google versus every security vendor." It is your measured Gmail baseline versus a finalist's incremental result.

Proofpoint Core Email Protection

Editorial best fit: Organizations that want a dedicated email-security layer and need to evaluate a secure email gateway, a Microsoft 365 API connection, or both.
Documented evidence: Proofpoint's Core Email Protection page describes Microsoft 365 and Google Workspace coverage, Microsoft Graph API integration, and secure email gateway deployment.
Tradeoff to examine: More than one deployment option can help fit an existing environment, but it also creates architecture choices around routing, coexistence, administration, and incident response.
Verify before buying: Ask Proofpoint to diagram the proposed connection for your tenant. Then test pre-delivery and post-delivery behavior, false-positive release, search and remediation, administrator evidence, and coexistence with native controls.

Vendor-published detection rates are not used here because they are not equivalent to an independent test in your environment.

Cloudflare Email Security

Editorial best fit: Teams that want to compare several documented deployment patterns and can evaluate how each pattern changes timing, routing, and remediation.
Documented evidence: Cloudflare's current reference architecture documents inline MX, Microsoft 365 API, BCC or journaling, and mixed deployments. It also states that its API model scans after initial delivery and describes tradeoffs among connection methods.
Tradeoff to examine: Deployment flexibility is useful only if the chosen architecture matches the required intervention point. Measure an after-delivery workflow for message exposure and remediation time. Review an inline design for mail-flow and continuity effects.
Verify before buying: Select the proposed architecture before the trial. Measure when each test message becomes visible, when action occurs, what users see, how administrators reverse mistakes, and which functions differ by deployment.

This is a deployment-fit recommendation, not a claim that one Cloudflare connection method detects more phishing than another.

Abnormal Inbound Email Security

Editorial best fit: Microsoft 365 or Google Workspace teams that want to test an API-connected behavioral layer without changing MX routing.
Documented evidence: Abnormal's Inbound Email Security page describes an API connection without MX record changes, Microsoft 365 and Google Workspace coverage, and analysis using identity, behavior, and content signals.
Tradeoff to examine: "No mail-flow change" does not remove integration work or prove faster detection. Buyers still need to test authorization scope, message visibility, remediation timing, exception handling, and the evidence available to analysts.
Verify before buying: Use organization-specific impersonation and vendor-conversation scenarios, measure how quickly a delivered message is found and remediated, review false positives, and confirm the steps for investigation and rollback.

Treat behavioral language as a product design description until your trial demonstrates a useful operational result.

How to choose

Define the scenarios and weights before demonstrations. Keep an evidence link for every score, and leave a field blank when the trial did not test it.

anti_phishing_decision_scorecard:
  deployment_fit:
    weight: 25
    evidence: "architecture diagram, permissions, mail-flow changes"
    score_1_to_5: null
  protection_scope:
    weight: 25
    evidence: "results from the same impersonation, link, attachment, and spoofing cases"
    score_1_to_5: null
  response_operations:
    weight: 20
    evidence: "time to investigate, remediate, release, and reverse"
    score_1_to_5: null
  false_positive_control:
    weight: 15
    evidence: "business-mail sample, exception workflow, user impact"
    score_1_to_5: null
  reporting_and_ownership:
    weight: 10
    evidence: "audit trail, role model, tenant or client reporting"
    score_1_to_5: null
  full_cost:
    weight: 5
    evidence: "license, deployment, operations, training, and response costs"
    score_1_to_5: null
decision_rule: "Do not score a criterion without trial evidence."

For an MSP, run the exercise twice: once for protection quality in a representative client tenant and once for delegated administration, cross-client visibility, policy variance, reporting, and client-safe remediation.

1. Measure the native baseline

Turn on the appropriate recommended controls, document exceptions, and run representative tests.

2. Write the gap in operational terms

Examples include missed supplier impersonation, slow cross-mailbox remediation, weak investigation evidence, or excessive policy work across clients.

3. Choose deployment constraints

Decide whether MX changes, after-delivery remediation, journaling, or broad API permissions are acceptable before inviting vendors.

4. Run the same trial

Use approved simulations and known-good business mail. Do not send realistic phishing to users without authorization and safeguards.

5. Calculate full cost

Compare current written quotes and include deployment, administrator time, user support, incident response, and renewal terms.

6. Document the decision

Preserve test messages, timestamps, false positives, screenshots or exports, and the reason each score was assigned.

Where DMARC fits

Inbound anti-phishing software and sender-domain authentication solve different parts of the problem. RFC 9989 defines DMARC as a way to validate authorized use of the domain in the visible From field and publish handling policy and reports. The standard explicitly does not assert that message content is valuable or legitimate.

That makes DMARC useful against direct domain spoofing, but not a replacement for controls that evaluate display-name impersonation, lookalike domains, malicious links, attachments, or compromised accounts. For a broader defensive model, see how anti-spoofing protects a brand from impersonation.

Check the sender-domain control beside your phishing stack

Use Palisade's DMARC checker to inspect a domain's published DMARC record while you document the email-authentication side of the buying decision. The checker can show the published record and policy evidence. It cannot test an inbound mail filter, block a phishing message, or prove that any vendor is effective.