{"id":81863,"date":"2024-09-16T20:05:59","date_gmt":"2024-09-16T20:05:59","guid":{"rendered":"https:\/\/mailrelay.com\/glossary\/headers\/"},"modified":"2025-02-24T19:47:02","modified_gmt":"2025-02-24T19:47:02","slug":"headers","status":"publish","type":"glossary","link":"https:\/\/mailrelay.com\/en\/glossary\/headers\/","title":{"rendered":"Headers"},"content":{"rendered":"\n

Email headers are lines of code at the top of the message that provide essential information about the email. <\/strong>
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They include, among others, the sender, the recipient, the date and time the message was sent, and the subject line.
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However, they go beyond these basic elements, also including technical fields such as ‘Reply-To’, ‘Content-Type’, and ‘List-Unsubscribe<\/a>‘, among others.
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These headers are essential for email systems and servers to correctly identify and process messages.
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Relevant historical data<\/h2>\n\n\n\n

The origin of email headers dates back to the early stages of email, in the 1970s<\/strong>, when the foundations for digital communication were laid.
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Over time, as email evolved from an academic and military communication medium to a universal tool, the structure and functionality of headers expanded.
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Standards such as Simple Mail Transfer Protocol (SMTP<\/strong>) and Internet Message Format played key roles <\/strong> in defining how headers are structured and used for efficient and secure communication.
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Key considerations<\/h2>\n\n\n\n

When designing and sending emails, it is vital to carefully consider headers.
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(Although in the case of the more technical settings, this will be done transparently by the email marketing tool<\/a>).
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A well-written ‘Subject<\/a>‘ header can determine whether an email is opened or ignored.
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The ‘From’ header should clearly identify the sender, establishing trust and recognition. <\/strong>
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In addition, technical headers, although not visible, must be configured correctly to avoid spam filters and ensure deliverability.
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The implementation of the ‘List-Unsubscribe’ header is especially relevant in email marketing, offering recipients a direct way to unsubscribe.
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Why it is important, advantages<\/h2>\n\n\n\n

Email headers are more than just technical components.
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They are basic tools in email marketing.
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Proper configuration and use of headers can lead to better delivery rates, increase open and click-through rates<\/strong>, and improve the recipient’s perception of the sender.
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This translates into more effective email campaigns, with a direct impact on marketing results.
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In addition, headers play a crucial role in email authentication and the fight against phishing and spam.
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Implementing headers such as ‘SPF<\/a>‘, ‘DKIM<\/a>‘, and ‘DMARC<\/a>‘ helps verify sender identity, building trust with email service providers.
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Conclusion<\/h2>\n\n\n\n

Email headers are fundamental components of the email marketing infrastructure, essential for boosting delivery rates and your marketing strategy.
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Their proper implementation ensures not only that messages reach their destination but also that they are positively received by recipients.
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In a world where the inbox is constantly cluttered, headers offer an opportunity to stand out, build trust and foster effective communication.
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