Using multiple synonym domains for email campaigns is generally considered risky for deliverability. Experts, marketers, and technical documentation all point to a potential dilution of sender reputation, increased complexity in managing authentication (SPF, DKIM, DMARC), and a higher likelihood of triggering spam filters. Multiple domains can confuse recipients, making them vulnerable to phishing, while consolidating efforts under a single, well-managed domain or using subdomains is generally recommended for better brand consistency, streamlined authentication, and improved deliverability.
13 marketer opinions
Using multiple synonym domains for email sending presents several risks to deliverability. It can dilute sender reputation, trigger spam filters, and confuse recipients. Managing authentication (SPF, DKIM, DMARC) across multiple domains is complex, and building trust is harder with inconsistent branding. Consolidating email efforts under a single, well-managed domain or using subdomains is generally recommended for better deliverability and brand consistency.
Marketer view
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.
21 Mar 2022 - Email Geeks
Marketer view
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.
30 Jan 2022 - StackOverflow
2 expert opinions
Experts agree that using multiple 'cousin' or synonym domains is risky for email deliverability. These domains can be seen negatively by mailbox providers, especially without a strong history or clear purpose. It's recommended to focus on building reputation with a smaller set of well-managed domains or using subdomains, which inherit the reputation of the main domain and prevent brand reputation dilution.
Expert view
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.
25 Aug 2023 - Word to the Wise
Expert view
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.
9 May 2024 - SpamResource
4 technical articles
Technical documentation emphasizes the risks of using multiple domains for email deliverability. Google, Microsoft, and DMARC.org all highlight the fragmentation of sender reputation and increased complexity in managing authentication protocols like SPF and DMARC. Maintaining separate SPF records and DMARC policies for each domain adds overhead and potential errors, and can trigger spam filters due to difficulty in verifying sender identity. Consistent sending from a single domain is crucial for building a positive reputation.
Technical article
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.
7 Jan 2023 - Google Postmaster Tools
Technical article
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.
27 Nov 2023 - DMARC.org
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