Sending emails to individuals who have viewed a product but have not explicitly opted-in is generally not recommended due to potential harm to sender reputation, deliverability issues, legal implications (GDPR, CAN-SPAM), and ethical concerns. Experts and marketers suggest prioritizing permission-based marketing, building engaged subscriber lists through opt-in methods, and ensuring transparency in data collection practices.
11 marketer opinions
Sending emails to individuals who have viewed a product but haven't explicitly opted-in is generally discouraged due to potential damage to sender reputation, deliverability issues, and legal implications (GDPR, CAN-SPAM). Experts recommend prioritizing permission-based email marketing, building engaged subscriber lists through opt-in methods, and providing valuable content to encourage subscriptions. Contacting non-opted-in users is considered unethical by some, and could be a waste of resources.
Marketer view
Marketer from Email Geeks explains that the original question wasn't intended as a deliverability question but more about whether it's worth flooding people with emails who are looking at products. He adds that if these people didn’t opt in then that provides a stronger argument that it is not worth it, as that approach is likely to lead to deliverabilty problems.
25 Nov 2023 - Email Geeks
Marketer view
Email marketer from Reddit shares that emailing people who visited your website without opting in is a terrible idea. He explains that it will get your domain blacklisted very fast. You need to get people to subscribe to your list first, and use lead magnets to attract subscribers
5 Jul 2023 - Reddit
3 expert opinions
Experts advise against sending emails to individuals who viewed a product but didn't opt-in due to the increased risk of spam reports and the lack of permission. Obtaining email addresses without consent, especially through methods like web scraping, raises concerns about deliverability and ethical email marketing practices. Permission is key.
Expert view
Expert from Word to the Wise explains that sending emails without permission is not advisable. She uses the analogy: "It's like walking up to someone on the street and trying to sell them something they didn't ask for."
22 Jan 2022 - Word to the Wise
Expert view
Expert from Email Geeks explains from a deliverability standpoint, assuming emails are going primarily to consumer domains, the risk is people will report it as spam. She asks how the email addresses were obtained and if people opted in at some point or if a service was used to discover email addresses of website visitors.
4 Apr 2025 - Email Geeks
5 technical articles
Sending emails to individuals who viewed a product but didn't opt-in is problematic due to legal regulations (GDPR, CAN-SPAM), deliverability risks, and the likelihood of triggering spam traps and blacklisting. Documentation emphasizes the importance of explicit consent, implementing double opt-in processes, and maintaining clean, validated email lists.
Technical article
Documentation from Spamhaus shares that Sending emails to addresses obtained without consent or through scraping methods is a major factor in triggering spam traps and being blacklisted. Spamhaus is a spam blacklist provider, so they advise against sending to non-opted in users.
21 Feb 2024 - Spamhaus
Technical article
Documentation from GDPR explains that under GDPR, sending marketing emails without explicit consent is illegal. Consent must be freely given, specific, informed, and unambiguous.
11 Sep 2023 - GDPR
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