How does domain reputation affect subdomain reputation in email marketing?

Email marketer from Neil Patel shares that a strong root domain builds trust for all subdomains. A positive reputation at the domain level helps subdomains gain credibility faster.

Email marketer from Reddit user u/EmailExpert123 shares that if subdomains are used for different purposes (transactional vs marketing), problems in one subdomain can affect the overall domain reputation if not properly managed. Consistent monitoring is crucial.

Email marketer from StackExchange User456 answers that while using separate IP addresses for subdomains can isolate some reputation issues, major domain-level blacklists will often consider the entire domain, irrespective of IP separation.

Email marketer from SendGrid explains that segmenting your email sending by using subdomains for different email types, like transactional and marketing, is a good strategy but that bad practices on a subdomain can still have negative repercussions on the main domain's sending reputation.

Email marketer from Mailjet states that domain reputation impacts all subdomains. Bad sending practices at the domain level tarnish the reputation of all subdomains.

Email marketer from SparkPost responds that isolating email streams with subdomains does not completely shield the main domain from reputation damage. Poor sending practices on subdomains can still negatively influence overall domain reputation.

Email marketer from Litmus responds that subdomain health contributes to the overall domain health. Consistent monitoring of email metrics across all subdomains helps maintain a strong domain reputation.

Marketer from Email Geeks shares that Spamhaus consolidates all the subdomains into domain reputation and uses that to determine spam.

Email marketer from EmailToolTester states that ISPs often group subdomains together when assessing sender reputation. A poor reputation on one subdomain can negatively impact the deliverability of emails from other subdomains.

Expert from Word to the Wise, Dennis Dayman, explains that bad sending habits on subdomains negatively impact the reputation of the overall domain. He says it's crucial to maintain good sending practices on all subdomains to safeguard the reputation of the primary domain.

Expert from Spam Resource, Laura Atkins, shares that subdomain reputations contribute to the overall domain reputation. She mentions that mailbox providers often evaluate the entire domain, so the sending practices on subdomains affect the main domain's trustworthiness.

Expert from Email Geeks explains that ML engines at places like Gmail and Microsoft look at all the mail for a domain, no matter what the subdomain is. She visualizes that subdomain reputations feed into the primary domain reputation and the primary domain reputation feeds down to the subdomains.

Expert from Email Geeks points out if salespeople are sending mail to cold leads without an unsubscribe link they’re breaking CAN SPAM and CASL, and likely aren't including a physical address which is also a CAN-SPAM violation.

Documentation from Google Workspace Admin Help explains that while each subdomain has its own specific reputation, a domain with a poor sending reputation can negatively impact the deliverability of emails sent from its subdomains.

Documentation from Microsoft explains that Microsoft Defender for Office 365 considers the entire domain when evaluating sender reputation, meaning that issues with email practices on a subdomain can potentially affect the deliverability of emails sent from the main domain.

Documentation from RFC specifies that using SPF records on the primary domain can affect subdomain authentication, depending on how the SPF record is configured. If the primary domain's SPF record includes subdomains, any authentication issues will impact the entire domain family.