Is it a good idea to put an email address in the subject line?

Email marketer from Mailchimp Resource shares that while there are no hard and fast rules, using email addresses in subject lines can be risky. They recommend focusing on clarity, brevity, and personalization to increase open rates and avoid spam filters.

Email marketer from Email on Acid states that email subject lines should be carefully crafted to avoid being marked as spam. It says that it is not a good practice to include an email address in the subject line.

Email marketer from Campaign Monitor suggests that the best subject lines are personalized and relevant to the recipient. They state that, as a result, putting an email address within the subject line is a poor practice.

Email marketer from Neil Patel's Blog explains that using email addresses in the subject line can come across as spammy and reduce open rates. He suggests personalizing the subject line with the recipient's name or other relevant information instead.

Email marketer from Email Geeks agrees that using an email address in the subject line might be interpreted as spam by Gmail, as spammers sometimes pull out the local part of the domain for personalization.

Email marketer from Reddit shares that putting email addresses in the subject can make your email look like spam because spammers often scrape emails and put them in the subject to look personalized. They recommend using personalization tokens with customer names to increase open rates.

Email marketer from Quora explains that using an email address in a subject line is often not a good idea, as it can appear impersonal and spammy. Instead, it is better to use the recipient's name or mention something specific to their interests.

Email marketer from HubSpot Blog suggests that including an email address in the subject line is generally not recommended. They suggest focusing on creating a sense of urgency or intrigue, asking a question, or offering a valuable benefit to encourage opens.

Expert from Email Geeks says that aside from people giving fake addresses in forms, putting an email address in the subject line might look spammy but suggests testing it.

Expert from Email Geeks suggests using first and last name instead of an email address in the subject line, mentioning that not everyone knows people by their email address and that CASL requires full disclosure of the "friend" sending the message.

Expert from Email Geeks agrees with Matt V that using a person's name in the subject line may look more legitimate than using an email address, as anyone can put anyone's email address in the subject line.

Expert from Word to the Wise, Laura Atkins, explains that subject lines should be designed to be relevant and helpful to the recipient, while avoiding phrases, punctuation, and techniques that trigger spam filters. She implies that including an email address could potentially trigger these filters, depending on context and sender reputation.

Documentation from Sendgrid explains that email deliverability is key, and the email subject line is one of the most important components. They state that the best approach is to avoid using any email address.

Documentation from Microsoft Support explains that including email addresses or URLs from untrusted sources in the subject line can increase the likelihood of emails being marked as spam. They suggest ensuring sender reputation and proper authentication to improve deliverability.

Documentation from Google Postmaster Tools recommends avoiding suspicious subject line content that can trigger spam filters. While they don't specifically mention email addresses, the guidance implies it is best to avoid anything that could be misinterpreted as spam.

Documentation from Spamhaus Wiki advises against using email addresses in the subject line, as it is a common tactic used by spammers. They recommend avoiding anything that could trigger spam filters, including suspicious punctuation, excessive capitalization, and certain keywords.

Documentation from Constant Contact indicates that subject lines should be concise and engaging. The recommendation implicitly advises against including email addresses in subject lines, which could potentially detract from clarity and engagement.