Key takeaways
- Email headers contain critical metadata, including sender information, routing details, and authentication results that help verify message legitimacy
- Understanding email header examples helps you spot phishing attempts, with 82.6% of phishing emails now AI-generated
- Authentication protocols like SPF, DKIM, and DMARC in headers protect against spoofing attacks
- Email header analysis can fix deliverability issues and ensure compliance with Google and Yahoo sender requirements
- Using header data enables powerful inbox organization through filters, labels, and automated sorting
Whether you're sending a personal note to a client, a response to a colleague, or email marketing like a newsletter, understanding email header examples is essential for managing your inbox effectively. The email header contains valuable technical information that helps you simplify and organize your email.
Most email clients have features that allow you to sort, organize, and filter emails by header information. AI-native email like Superhuman Mail makes it especially easy to use email header information to stay on top of your inbox. Plus, the data in email headers helps you stay safe from scams, spam, and phishing attacks.
Let's explore what email headers are, walk through real examples, and show you how to use them to your advantage.
What is an email header?
The email header contains metadata like the sender, recipient's email address, date and time information, and other technical details unique to that specific email. These headers aren't immediately visible but can be accessed through your email service provider when you click on an option such as "view message source" or "original message."
Think of email headers as the digital equivalent of a postal envelope's postmarks and routing stamps. While you typically only see the "From" and "Subject" lines in your inbox, a wealth of information travels behind the scenes with every message. Every email message you send or receive includes this header information, making email headers a powerful tool for managing and organizing your inbox. Let’s jump right into it!
9 email header examples you need to know
Before diving into the technical details, here are nine real email header examples that show exactly what this data looks like. These professional email header examples demonstrate the different fields you'll encounter when analyzing any email.
1. From header example
From: Jane Smith <jane.smith@company.com>The From header identifies the sender's display name and email address. This is the most recognizable header field and appears in your inbox view.
2. To header example
To: John Doe <john.doe@business.org>The To header shows the primary recipient's information. Multiple recipients appear separated by commas.
3. Subject header example
Subject: Q4 Marketing Report - Action RequiredThe Subject header contains the email's subject line exactly as the sender typed it. Clear subject lines improve email deliverability and open rates.
4. Date header example
Date: Mon, 15 Jan 2025 09:32:45 -0500The Date header shows the exact timestamp when the email was sent, including the sender's timezone offset.
5. Reply-to header example
Reply-To: support@company.comThe email header reply-to field directs responses to a different address than the sender. This is common for business email header examples where teams share inboxes.
6. Message-ID header example
Message-ID: <CADfk8jK2xYp9N4vL1mR7wQ3hT5sB8cF@mail.company.com>The Message-ID is a unique identifier automatically generated for every email. No two emails share the same Message-ID.
7. Received header example
Received: from mail-server.company.com (192.168.1.100)
by mx.recipient.org with ESMTPS id abc123
for <john.doe@business.org>;
Mon, 15 Jan 2025 09:32:47 -0500The Received header traces the email's path through mail servers. Multiple Received headers appear in sequence, read from bottom to top.
8. Authentication-Results header example
Authentication-Results: mx.google.com;
spf=pass (google.com: domain of jane.smith@company.com designates 192.168.1.100 as permitted sender);
dkim=pass header.d=company.com;
dmarc=pass (p=REJECT) header.from=company.comThis email header analysis example shows SPF, DKIM, and DMARC all passing, indicating a legitimate, properly authenticated email.
9. Return-Path header example
Return-Path: <bounces@company.com>The Return-Path specifies where bounce notifications go if the email cannot be delivered. This may differ from the From address in business email header examples.
Main elements of an email header
An email header can contain many different fields, some of which are mandatory and some that are specific to the email service provider or how the email was created. Each email has unique header elements, ranging from simple sender information to technical specs. Here are the key email header elements you'll encounter when reviewing professional email header examples.
Informational headers
The informational headers contain the basic details most users recognize. The From field shows who the email came from, including the sender's name and email address. The To field displays the receiver's name and email address. Cc/Bcc fields show carbon copy and blind carbon copy recipients, though Bcc addresses are intentionally hidden from headers for privacy.
The Subject line contains any text that the sender entered in the subject line field. The Date is a mandatory field that includes the timestamp and date the email was sent. The Reply-to field is optional and lists the specific email address where any response will be delivered, which could be different from the sender's email.
Technical headers
Technical headers provide the routing and formatting details. The Message-ID is a unique code made up of about 50 letters and numbers that is automatically created when you send an email. The Return-Path functions like a return address for a letter, showing the email address that a message will be sent back to if it can't be delivered to the intended recipient.
The Content-Type field describes the format of an email's message, such as HTML, TXT, or multipart (which can include both text and HTML components). MIME-version details the Multipurpose Internet Mail Extensions protocol used for formatting the email, which allows emails to include attachments and HTML formatting. The Received field shows the path that the email took to get to the recipient after going through an SMTP server.
Security and authentication headers
Security headers are critical for verifying email authenticity. SPF (Sender Policy Framework) is an email authentication method designed to detect if a sender is forging addresses during the delivery of the email. DKIM-Signature (DomainKeys Identified Mail) is an authentication method used to validate that the email was actually sent and authorized by the owner of that domain.
Authentication-Results is a consolidated field showing the pass/fail status of SPF, DKIM, and DMARC checks. X-Headers are custom headers added by email clients or servers that provide more information on tracking data or anti-spam measures. From the highly technical to the basic, each element of an email header provides information that can be used to manage your inbox.
Why email headers matter for security
An email header can provide valuable information about the message source, routing, and delivery of your email. This information can help you identify any potential threats and confirm the legitimacy of an email.
Email headers can help you spot phishing attempts or suspicious emails, which could be a cybersecurity risk. By carefully examining the Return-Path, authentication results (SPF, DKIM, and DMARC), and tracing the email's routing path through the "Received" lines, you can verify that the sender's information is legitimate and avoid responding or interacting when something looks malicious.
The stakes have never been higher. The FBI's IC3 2024 report documented $2.77 billion lost to Business Email Compromise (BEC) scams in 2024, with 63% of organizations facing BEC attacks according to the AFP's 2025 Fraud and Control Survey.
When examining headers for security purposes, look for these red flags:
- Mismatched domains where the "From" address doesn't match the "Return-Path"
- Authentication failures showing SPF, DKIM, or DMARC "fail" results
- Suspicious routing through unexpected servers or geographic locations
- Unusual X-headers with spam filter warnings or security flags from email providers
These indicators can help you identify potentially malicious emails before you engage with them.
How email headers improve deliverability
Email deliverability has become increasingly challenging. The global inbox placement rate dropped to 83.5% in 2024, with spam folder rates averaging 6.7% for the year.
If your email delivery is hit-and-miss or your emails are regularly landing in a recipient's spam folder, you can look at your header information to see where things might be going wrong. The email's path (contained in the Received field) can help you identify any IP address issues or delivery problems that could be preventing your emails from reaching the recipient.
In February 2024, Google and Yahoo implemented significant email authentication requirements that directly impact deliverability. All senders must now implement SPF or DKIM authentication, valid DNS records, TLS encryption, and maintain spam rates below 0.3%. All senders must now implement SPF or DKIM authentication, valid DNS records, TLS encryption, and maintain spam rates below 0.3%. Bulk senders (5,000+ messages per day) face additional requirements including mandatory DMARC implementation, domain alignment for authentication, and one-click unsubscribe functionality.
Using email headers to organize your inbox
Beyond the technical aspects, email headers contain valuable metadata that enables powerful inbox organization and management capabilities. By using the data found in message headers, such as sender information, routing details, and authentication results, you can set up rules to automatically sort incoming emails into specific folders, apply labels based on priority or sender, and create filters that help you manage inbox overload.
This automation makes it easier to navigate your email, prioritize responses, and maintain control over high-volume inboxes. When you examine the technical data in an email message header, you can trace the route the email followed to reach your inbox. This includes a record of the IP addresses involved in the transmission process. The "Received" headers are read from bottom to top, showing each server the email passed through.
Email headers also play a critical role in regulatory compliance. The FTC's CAN-SPAM Act requires headers to contain accurate sender, recipient, and routing information. Headers are also essential for GDPR, HIPAA, and Sarbanes-Oxley compliance, as they form part of the metadata preserved in compliant archiving solutions. For legal matters, email headers provide forensic evidence of origins, timing, and routing information that can support cybersecurity investigations.
How to find email headers in popular email clients
So, where can you find email headers in your own inbox? Here's how to find the data you're looking for in various email clients.
What is an email header in Gmail
To find an email header on Gmail, open the email you want to look closer at. Click on the three vertical dots in the top-right corner of the message. Select "Show Original" from the dropdown menu. A new window will open that displays the full email header, showing you a complete professional email header example with all authentication results and routing information.
Outlook
On Outlook, you can find an email header with these steps. Open the email you want to view, then click on the "File" menu. Select "Properties." In the "Internet headers" section at the bottom, you'll find the complete email header information, including sender authentication details (SPF, DKIM, DMARC results), routing history via "Received" entries, and technical metadata about how the email was transmitted. For Outlook on the web, click the three dots, select "View" and then "View message source."
Apple Mail
On Apple Mail, find an email header by doing the following. Open the email you wish to check. In the menu bar, select View. Select "Message" and then "All Headers." The full header information will be displayed at the top of the email.
Yahoo Mail
To find an email header in Yahoo Mail, open the email you're interested in. Click on the "More" (three dots) button on the right side of the screen. Select "View Raw Message." A new window will display the complete header information.
Mobile email clients
Viewing email headers on mobile devices is more limited. Most mobile email apps don't provide direct header access. For iOS Mail and Android Gmail, you'll typically need to forward the email to yourself and view headers on a desktop client, or use the webmail version through your mobile browser.
Email header analysis tools
If manually parsing email headers feels overwhelming, several tools can help automate the analysis. Google Admin Toolbox Messageheader is a free tool that parses headers and presents information in an easy-to-read format, showing delivery delays and routing paths.
MxToolbox Email Header Analyzer provides detailed analysis, including authentication results, delivery times, and potential issues. Microsoft Message Header Analyzer is useful for troubleshooting Outlook and Exchange-related delivery problems.
These tools can quickly highlight authentication failures, unusual routing patterns, or delivery delays that might indicate problems or security concerns.
How to use email headers to work more productively
Once you know how to find and understand the elements of email headers, it's time to use them to help you work more productively. The metadata in headers like From, To, Reply-To, and authentication results isn't just technical trivia. It's the foundation for powerful inbox organization and smarter email triage.
Most email clients let you create basic filters using header fields, but AI-native tools like Superhuman Mail take this further by automatically analyzing email metadata to keep your inbox organized without manual rule-building. Here's how:
- Split Inbox uses sender and recipient header data to separate important messages from less urgent ones automatically, with customizable splits for VIPs, team messages, newsletters, and notifications
- Auto Labels use AI to categorize incoming messages like a world-class executive assistant, automatically classifying emails into categories like marketing, cold pitches, social updates, and messages requiring your response
- Auto Summarize displays a one-line summary above every conversation that updates as new emails arrive, so you can often skip reading the full thread and focus only on what matters
- Read Statuses show you when recipients open your emails, giving you real-time visibility into whether your message landed and was seen
- Remind Me brings messages back to your inbox at the perfect time, so you never drop the ball when a Reply-To requires a delayed response or follow-up
- Ask AI lets you query your inbox with natural language, so you can instantly surface specific emails by sender, date, or content without manually searching through headers
Beyond productivity, email headers are also your first line of defense against compromised accounts. If you receive emails from colleagues that seem unusual, checking the email headers can reveal whether the message actually originated from expected servers.
Emails routing through unexpected geographic locations or unfamiliar mail servers could indicate a compromised account, a common BEC tactic requiring immediate security team notification. By examining the "Received" header chain and verifying that the From address aligns with the Return-Path, you can quickly identify spoofed emails attempting to impersonate trusted colleagues before clicking links or sharing sensitive information.
Mastering email header examples for security and productivity
Understanding email header examples is critical for protecting your business and optimizing your inbox. With a 2024 Harvard study finding that AI-generated phishing emails achieve 54% click-through rates compared to just 12% for traditional phishing, the ability to quickly verify email authenticity through headers is essential protection for you and your organization.
From small business owners to busy executives, email headers help you unlock peak productivity, enhance security, and prevent costly breaches in your daily work. Looking for an email solution that keeps your email organized as you go through your busy day? Superhuman Mail helps you keep your inbox tidy, secure, and calm, plus you'll fly through your inbox twice as fast. Try Superhuman Mail today.
FAQs
What is an example of an email header?
A professional email header example includes fields like From (sender's email address), To (recipient's address), Subject, Date, Message-ID, and authentication results such as SPF, DKIM, and DMARC pass/fail statuses. Technical headers also include Received fields showing the routing path and Return-Path for bounce handling.
How do I write a header for an email?
Email headers are automatically generated by your email client and mail servers. You don't write them manually. However, you can influence certain header fields by filling in the To, Cc, Bcc, Subject, and Reply-to fields when composing your message. For email header design in marketing emails, you control the visual header through your email template.
What makes a good email header?
A good email header has accurate sender information, proper authentication (SPF, DKIM, and DMARC passing), and clear routing information. For business email header examples, ensure your domain has proper authentication records configured, your Reply-to address is correct, and your Subject line clearly communicates the email's purpose.
Can someone find my physical location from email headers?
Email headers may contain IP addresses, but modern email services employ different privacy protections. Gmail typically masks sender IP addresses, while Outlook and Yahoo Mail primarily show the email provider's servers rather than your personal device's location in headers.
Can I see BCC recipients in email headers?
No. BCC (blind carbon copy) is designed to remain hidden from all recipients, including in the email headers. This privacy feature is intentional.
Why do authentication checks sometimes fail on legitimate emails?
Legitimate emails can fail authentication when forwarded, sent through mailing lists, or routed through third-party services. ARC (Authenticated Received Chain) headers help preserve authentication through forwarding chains, though adoption remains limited as this protocol is still emerging in email infrastructure.
