Phishing emails are becoming harder to spot. Attackers use real branding, familiar sender names, and urgent language to trick you into clicking malicious links or sharing credentials. Copilot in Outlook can help you analyze suspicious emails without leaving your inbox. This article explains how to use Copilot to detect phishing patterns by examining sender behavior, language cues, and embedded threats.
Copilot uses Microsoft Graph data and threat intelligence to evaluate an email’s risk factors. It does not replace your organization’s security filters. Instead, it gives you a second opinion when something feels off. You will learn the exact prompts to use, what to look for in the analysis, and how to avoid common mistakes.
By the end of this guide, you will be able to run a Copilot analysis on any email, interpret the results, and decide whether to report the message to your security team. You will also learn how to configure Copilot’s data sources to improve detection accuracy.
Key Takeaways: Using Copilot to Spot Phishing Attempts
- Copilot pane > Summarize > Analyze security: Generates a risk assessment of the selected email, flagging suspicious sender domains, mismatched URLs, and urgent language.
- Prompt: “Is this email a phishing attempt?” Triggers Copilot to examine the email’s headers, embedded links, and language patterns for common phishing indicators.
- Microsoft 365 admin center > Settings > Copilot > Data sources: Enables Copilot to access Microsoft Defender for Office 365 threat data for more accurate phishing detection.
What Copilot in Outlook Checks for Phishing
Copilot does not scan every email automatically. You must invoke it by opening the Copilot pane and selecting a specific email. Once you do, Copilot analyzes the following elements:
Sender Identity and Domain Reputation
Copilot checks whether the sender’s domain matches the display name. For example, an email from “Microsoft Security” sent from support@secure-login.co would be flagged as suspicious. Copilot also cross-references the domain against known threat databases if your organization uses Microsoft Defender for Office 365.
Language and Urgency Patterns
Phishing emails often use fear-based language: “Your account will be closed,” “Immediate action required,” or “Unauthorized login detected.” Copilot identifies these patterns and highlights them in its summary. It also compares the email’s tone against typical internal communications from the same sender.
Embedded Links and Attachments
Copilot examines every hyperlink in the email body. It compares the visible link text with the actual destination URL. If the URL contains typos, unusual top-level domains, or IP addresses instead of domain names, Copilot marks them as suspicious. Attachments with macros or executable files are also flagged.
Steps to Analyze an Email for Phishing with Copilot
- Open the suspicious email in Outlook
Select the email in your inbox. Do not click any links or download attachments. Leave the email in its original read or unread state. - Open the Copilot pane
Click the Copilot icon in the top-right corner of the Outlook window. The pane opens on the right side of your screen. - Click Summarize
Copilot generates a summary of the email. Read the summary to see if it matches the email’s apparent purpose. A mismatch between the summary and the email’s subject line is a red flag. - Ask Copilot to analyze security
In the Copilot pane, click the “Analyze security” button if available. If not, type the following prompt in the text box: “Analyze this email for phishing indicators. Check the sender domain, embedded links, and language for urgency or threats.” - Review the risk assessment
Copilot returns a list of findings. Look for these specific outputs:- Sender domain check: Shows whether the domain is legitimate or impersonated.
- URL analysis: Lists each link with the visible text and the actual destination.
- Language flags: Highlights phrases commonly used in phishing attacks.
- Attachment warning: Alerts you if an attachment contains risky file types such as .exe, .vbs, or .js.
- Use follow-up prompts for deeper checks
If Copilot does not flag an issue but you remain suspicious, ask: “Check if this email contains any mismatched URLs where the link text does not match the destination.” You can also request: “Compare this email’s language to the last three emails from the same sender.” - Report the email to your security team
If Copilot confirms suspicious patterns, forward the email to your IT security team as an attachment. Do not forward it as an inline message because that hides the original headers. Use Outlook’s “Forward as attachment” option.
Common Mistakes and Limitations When Using Copilot for Phishing Detection
Copilot Does Not Automatically Scan All Incoming Emails
Copilot only analyzes an email when you open the pane and request a summary or security analysis. It does not run in the background. If you want continuous scanning, your organization must use Microsoft Defender for Office 365 with Safe Links and Safe Attachments enabled.
Copilot Cannot Access External Threat Feeds
Copilot’s analysis is limited to Microsoft Graph data and your organization’s Microsoft 365 environment. It does not query third-party threat intelligence platforms unless your admin has connected them via Microsoft Sentinel or a custom connector. Relying solely on Copilot may miss zero-day phishing campaigns that use newly registered domains.
False Positives from Legitimate Marketing Emails
Marketing newsletters often use urgency language and trackable links. Copilot may flag these as suspicious. Always verify the sender’s domain and the link destinations manually before dismissing a Copilot warning. If you receive many false positives, ask your admin to adjust the sensitivity of Copilot’s security analysis.
Copilot Does Not Block or Delete Emails
Copilot is an analysis tool, not an enforcement tool. It cannot move emails to Junk, quarantine them, or block senders. You must take action manually or through your organization’s email security policies.
Copilot in Outlook vs Microsoft Defender for Office 365: Phishing Detection Comparison
| Item | Copilot in Outlook | Microsoft Defender for Office 365 |
|---|---|---|
| Detection method | On-demand analysis via user prompts | Automatic scanning of all inbound emails |
| Data sources | Microsoft Graph, email headers, link text | Microsoft threat intelligence, machine learning models, sandbox detonation |
| User action required | Yes – user must open Copilot pane and request analysis | No – emails are filtered before reaching inbox |
| Blocking capability | No – only provides analysis | Yes – can quarantine, block, or delete emails |
| False positive rate | Higher due to limited context | Lower due to broader threat data |
Copilot is best used as a supplement to Defender. When you receive an email that passes Defender’s filters but still looks suspicious, use Copilot to get a second opinion. If Copilot also flags it, report the email to your security team immediately.
You can now use Copilot in Outlook to examine emails for phishing patterns by checking sender domains, embedded links, and urgency language. Start with the “Analyze security” button or the prompt “Is this email a phishing attempt?” to get a baseline risk assessment. For more accurate results, ask your Microsoft 365 admin to enable Copilot’s access to Defender threat data in the admin center under Settings > Copilot > Data sources. If you encounter an email that Copilot does not flag but still feels wrong, use the prompt “Check for mismatched URLs in this email” to force a deeper link analysis.