How do you migrate an email sending domain from one platform to another?

Key findings

• Domain choice: It is generally recommended to migrate your existing sending domain or a subdomain of your main domain, rather than creating an entirely new domain. A new domain can confuse recipients and may be perceived as a phishing attempt.
• Subdomain preference: Using subdomains (e.g., mail.yourdomain.com) for sending is often preferred as it allows for better isolation of sending reputation from your main domain's reputation. When migrating, this existing subdomain can be reconfigured.
• Reputation continuity: Moving to a new domain can mean sacrificing accumulated sender reputation. There is no direct email equivalent to a 301 redirect in SEO to transfer domain authority, so a careful transition plan is crucial to avoid emails going to spam.
• Gradual migration: A gradual migration strategy is advisable. This involves setting up the new ESP and slowly shifting sending volume, rather than an abrupt cutover. This allows for observation and adjustment.
• IP and subdomain warming: Even if you migrate the same subdomain, if the new ESP uses different IP addresses, IP warming and some subdomain warming will still be necessary for the new infrastructure.

Key considerations

• Simultaneous sending: Consider if you need to send from both platforms simultaneously during the transition period, possibly as a fallback or for a phased migration. This impacts DNS configuration.
• DNS management: Carefully manage DNS records (SPF, DKIM, DMARC) for the sending domain. It is ideal for the client to maintain control of these DNS records rather than delegating them entirely to an ESP for security and flexibility. More information on DNS management during migration can be found in this guide on migrating branded sending domains.
• MX records: While a subdomain can be used with multiple providers, the MX record for that subdomain can only point to one location at a time. Plan the switch of MX records carefully based on your migration timeline.
• Reply-to and tracking domains: The reply-to domain generally has less impact on deliverability. Tracking links, however, will change with a new ESP and are marginally customer-visible, requiring careful setup.
• Monitoring: Closely monitor deliverability performance with your new ESP to identify and resolve any issues promptly.

Key opinions

• Brand continuity: Creating a new domain can confuse consumers and potentially make them more susceptible to phishing attempts, as they are trained to expect emails from a specific sender identity.
• Reputation loss: Abandoning an existing domain means losing its accumulated sender reputation, which has a significant impact on deliverability.
• Subdomain benefits: Using a subdomain of the main domain is a common practice, and marketers prefer to use these subdomains when migrating between ESPs.
• Phased approach: Marketers advocate for a gradual, monitored transition, acknowledging that any change can initially appear suspicious to Mailbox Providers (MBPs).

Key considerations

• DNS delegation: While convenient, delegating subdomain DNS to an ESP can pose security risks. It's often better to manage DNS records yourself and update them as needed for the new provider.
• Dual sending: It's possible to use the same domain in the From: header across two different providers simultaneously, even with different return paths. The main change visible to customers will be tracking links.
• IP warming: A new ESP typically means new IP addresses, necessitating a thorough IP warming process in the new environment.
• Retain old platform: Do not cancel the old platform immediately. Keeping it active for a period provides a fallback or disaster recovery option in case the migration encounters issues. More on this topic can be found in this guide on switching email service providers.

Key opinions

• Domain stability: Experts generally recommend migrating the existing domain or a subdomain due to the significant negative impact a new domain can have on consumer trust and phishing vulnerability.
• Reputation preservation: The hard-earned sender reputation of an existing domain is a valuable asset that should not be discarded by switching to an entirely new one. Strategies should focus on transferring this reputation effectively.
• Phased transition: A gradual migration, potentially involving simultaneous sending from both platforms for a period, is crucial to manage deliverability and allow for observation and adjustments without abrupt changes.
• DNS control: Maintaining direct control over your domain's DNS records, rather than delegating to an ESP, offers greater security and flexibility in managing authentication and delivery.

Key considerations

• IP and domain warm-up: Even with a subdomain migration, new IPs from the new ESP require a dedicated warming process to build trust with receiving mail servers.
• Authentication setup: Ensure all email authentication protocols (SPF, DKIM, DMARC) are correctly configured for the new ESP. This is vital for maintaining deliverability and preventing your emails from being flagged as spam. Refer to this guide on setting up email authentication for multiple ESPs.
• Blacklist monitoring: Proactive blocklist monitoring during migration is essential. Any deliverability issues could lead to a domain or IP being placed on a blacklist, affecting future sending.
• Deliverability metrics: Continuously track key deliverability metrics such as inbox placement rates, open rates, click-through rates, and complaint rates to quickly identify and address any declines post-migration.

Key findings

• DNS configuration: Documentation frequently details the specific DNS records (e.g., CNAME, MX) required to set up a sending domain or subdomain with a new ESP.
• Authentication setup: Comprehensive guides walk through setting up SPF, DKIM, and DMARC for the new sending environment to ensure emails are properly authenticated.
• Dedicated sending domains: Many ESPs offer or encourage setting up a dedicated sending domain or branded sending domain to give users full control over their sender reputation and deliverability.
• Migration checklists: Documentation often provides step-by-step checklists, covering everything from signing up with a new provider to redirecting domain names and setting up email addresses.

Key considerations

• Impact on deliverability: Guides consistently warn that inadequate migration can harm deliverability, often requiring a warm-up period for new IPs and domains to build trust with ISPs.
• Data migration: Instructions frequently include advice on how to export and import email lists, contacts, and historical data from the old platform to the new one.
• Testing and monitoring: Post-migration, continuous testing and monitoring of email performance are advised to catch and rectify any issues swiftly.
• Transfer locks: When transferring a domain registrar, documentation advises checking domain transfer requirements, unlocking the domain, and obtaining an authorization code, as detailed by WordPress.com support.