What are the best practices for mailing duplicate opt-ins and how do they affect deliverability?

Email marketer from Neil Patel Digital explains that sending too many emails to the same subscriber can lead to decreased engagement and increased unsubscribe rates. Segmenting lists and personalizing content can help.

Email marketer from Email Geeks suggests exploring why users are signing up repeatedly and whether they are using domains that provide complaint feedback loops before deciding how to manage the situation.

Email marketer from Quora explains that If you're finding subscribers on your list multiple times, it means you have issues with list hygiene and you need to clean up your list as it can be a big turn-off if the same person is receiving your emails over and over again.

Email marketer from ActiveCampaign recommends the use of automation and segmentation to determine if a customer resubscribes within a specific time period, they can get a different email flow than the original sign up as they know they are already familiar with the brand

Email marketer from Reddit shared that they implemented a system to flag duplicate sign-ups within a short period. If a user signs up again within a week, they receive a different welcome email acknowledging their repeated interest, but aren't bombarded with the original welcome series.

Email marketer from Mailchimp shares that regularly cleaning email lists and removing inactive or duplicate subscribers is crucial for maintaining a healthy sender reputation and improving deliverability. Engagement metrics like open and click rates are key indicators.

Email marketer from HubSpot explains that using HubSpot's deduplication tools helps identify and merge duplicate contacts, preventing sending multiple emails to the same person and ensuring accurate data.

Email marketer from Email Geeks suggests rewarding loyalty instead of sign-ups or providing the thing they are seeking outside of email. Also recommends having a preference center to let users choose mail type and frequency.

Email marketer from Sendinblue suggests the importance of regularly cleaning out your email list. If you're not doing this already, then it's probably high time you start. In the long run, it will significantly improve the overall quality of your email campaigns and make you an expert email marketer in the process

Expert from Word to the Wise explains that list bombing, where an email address is subscribed to multiple lists without consent, damages sender reputation and deliverability. Avoiding this practice is crucial.

Expert from Email Geeks suggests that if sign-ups with the same email address are occurring, there might be data management issues. If it's different email addresses, users know what they are signing up for.

Expert from Email Geeks explains one impact is that the most engaged users unsubscribe and the email program loses them forever.

Expert from Email Geeks explains that mailing duplicate opt-ins hurts deliverability if recipients don't want multiple copies and report them as spam.

Expert from Email Geeks explains duplicate content is likely to cause some of the mail to be marked as spam and the mail stream recognised as sending multiple identical mails, which is spam-like behaviour, that you’d also want to avoid.

Expert from Email Geeks suggests ISPs detect substantively similar emails and subsequently deprioritize (send to promo/spam) mail from a program that sends the same message to the same user multiple times.

Expert from Spam Resource explains that sunset policies, where inactive subscribers are removed from the list, are critical for maintaining engagement and deliverability. Mailing to old, unengaged addresses will lead to deliverability problems.

Expert from Email Geeks explains that sending duplicates of content makes no sense and will annoy recipients, leading to unsubscribes or spam reports. Suggests treating multiple entries to giveaways differently from subscriptions.

Documentation from Microsoft Learn shares that a positive sender reputation is crucial for deliverability. Sending duplicate or unwanted emails can harm your reputation, leading to emails being classified as junk.

Documentation from Gmail Help indicates that keeping spam rates low (below 0.1%) is essential for maintaining deliverability. Sending unwanted emails, including duplicates, can negatively impact your sender reputation.

Documentation from RFC 5322 explains that sending practices should respect the recipient and abide by email standards. Repeated emails should only be sent if the user has requested them.