Is it risky for deliverability to use several synonym domains that contain the main domain?
Summary
What email marketers say13Marketer opinions
Email marketer from Email Geeks shares that if you send any type of content which would be unexpected and/or unwanted then you run the risk of the ML based filters working out that all of the domains are logically connected.
Email marketer from StackOverflow explains that using multiple domains for the same brand can dilute your sender reputation and make it harder for email providers to identify you as a legitimate sender. Stick to a primary domain with well-configured authentication (SPF, DKIM, DMARC) for better deliverability.
Email marketer from Email Geeks responds that using domains like that can cause problems with establishing trust. Also consider if these different domains will cause confusion or not.
Email marketer from Email Geeks suggests better using sub-domains to separate different activities.
Email marketer from EmailOctopus Blog shares that consolidating your email efforts under a single, well-managed domain can lead to better deliverability rates. Spreading your sending across multiple domains might make it harder to track and optimize your sender reputation.
Email marketer from SendGrid Blog shares that while multiple domains can be used, subdomains offer better brand consistency and easier management of email authentication protocols like SPF and DKIM, which are crucial for deliverability.
Email marketer from Reddit explains that using too many similar domains can trigger spam filters, as it's a common tactic used by phishers. Focus on your main domain and use subdomains for different types of email.
Email marketer from Mailjet Blog explains that using multiple domains can dilute your sender reputation. It's generally better to focus on building a strong reputation for a primary domain rather than spreading your efforts across several.
Email marketer from Gmass Blog suggests that managing authentication (SPF, DKIM, DMARC) across multiple domains can be complex and prone to errors. It's generally easier to manage and monitor authentication for a single primary domain.
Email marketer from Litmus shares that you should consider the user experience. Will these different domains confuse recipients? Consistent branding across a single domain is generally better for building trust.
Email marketer from SuperOffice Blog explains that different domains need their reputation building up and maintaining. They share its simpler to have a single domain to do this for.
Email marketer from Email Geeks shares to think about what you are training your recipients to expect from your brand and if you're making it easier for them to be taken advantage of by phishers and malicious lookalike domains
Email marketer from Email Geeks shares to not use cousin domains, use subdomains. Cousin domains look like phish and train your users to trust phish. Subdomains can leverage the reputation of org or other sibling domains.
What the experts say2Expert opinions
Expert from Word to the Wise explains that using multiple 'cousin' domains can be seen as a negative signal by mailbox providers, especially if those domains don't have a strong history or clear purpose. It's generally better to focus on building reputation on a smaller set of well-managed domains or subdomains.
Expert from SpamResource shares that using subdomains is always best as it inherits the reputation of the main domain. Also, using separate sending domains should be avoided unless required as it dilutes the brand reputation.
What the documentation says4Technical articles
Documentation from Google Postmaster Tools explains that having a consistent sending domain helps build a positive reputation with Gmail. Using multiple domains can fragment your reputation and potentially harm deliverability.
Documentation from DMARC.org explains that DMARC policies are applied on a per-domain basis. Managing DMARC across multiple domains requires careful planning and monitoring to ensure consistent enforcement of your email security policies.
Documentation from RFC explains that SPF records are domain specific. If you're using multiple domains, you need to maintain separate SPF records for each, which can become a management overhead and potential source of errors.
Documentation from Microsoft details that using too many domains can make it harder for them to verify the senders identity. As a result this can trigger spam filters.