Summary
Switching to a new subdomain and domain in Salesforce Marketing Cloud (SFMC) for email authentication, such as implementing SPF, DKIM, and DMARC, often leads to an unexpected drop in deliverability. This counterintuitive outcome, where messages start going to spam or experience significant reductions in open rates and revenue, is a common challenge. The primary reason for this decline is the essential, but often overlooked, process of warming up a new domain or subdomain, even when using a shared IP within an ESP like SFMC. Unlike dedicated IP warming, domain warming is specifically about building sender reputation for the new domain combination. Ignoring this critical step can severely impact inbox placement and overall email campaign performance.
Key findings
- Reputation reset: A new sending domain or subdomain starts with no established reputation, regardless of previous sending history from a different domain or IP. Changing a subdomain impacts deliverability and requires a new warmup.
- Authentication is essential: While moving to authenticated domains (SPF, DKIM, DMARC) is mandatory with recent changes from Google and Yahoo, it does not negate the need for domain warming. It's a foundational requirement, not a shortcut to reputation.
- Subdomain vs. domain reputation: Each subdomain has its own reputation, which contributes to the overall reputation of the root domain. A poor subdomain reputation can negatively affect the main domain and vice versa.
- Shared IP nuance: Even on shared IPs within SFMC, domain warming is necessary. You are warming the combination of your domain/subdomain with that specific IP pool.
Key considerations
- Warmup strategy: Plan a gradual increase in sending volume to your most engaged subscribers on the new domain. This builds positive engagement signals with ISPs. For a guide, see Salesforce Trailhead on email subdomain warming.
- Monitor performance: Actively track deliverability metrics, including inbox placement, open rates, and spam complaints, using tools like Google Postmaster Tools. This helps you adapt your warming schedule as needed.
- Temporary fallback: If deliverability is severely impacted, consider temporarily reverting to the old, warmed domain for critical communications while you recover your domain reputation.
- Engagement first: Prioritize sending to your most engaged subscribers during the initial warming phase to generate positive signals and avoid spam traps.
What email marketers say
Email marketers often find themselves in a challenging situation after implementing necessary authentication changes in platforms like Salesforce Marketing Cloud. The expectation is improved deliverability, but the reality can be a significant drop in performance. This is primarily due to the new domain or subdomain lacking a sending reputation with ISPs, leading to messages being routed to spam folders. Marketers frequently report increased anecdotal spam complaints and measurable dips in open rates and revenue, highlighting the critical need for a structured domain warming strategy, even when an ESP's system is already configured with a Sender Authentication Package (SAP).
Key opinions
- Unexpected decline: Many marketers observe a noticeable decline in deliverability immediately after switching to a private or authenticated domain, which seems counterintuitive.
- Impact on metrics: Tangible effects include increased spam reports, substantial decreases in open rates (e.g., 40% year-over-year), and negative revenue impacts.
- Confusion around 'private domains': Some marketers are misinformed that private domains in Marketing Cloud (which often use shared IPs) do not require warming.
- Short-term solutions sought: There's a desire for immediate fixes or stop-gap solutions while long-term reputation building is underway.
Key considerations
- Warmup is mandatory: A new domain or subdomain always requires warming, even if the IP is shared or the Sender Authentication Package (SAP) is configured. This directly impacts why your emails might be going to spam.
- Subdomain reputation: While partially separated, a subdomain's reputation is interconnected with its root domain. Negative activity on one can influence the other.
- Engagement is key: Focusing on highly engaged subscribers during the warmup phase can help mitigate issues and build positive sender reputation signals more quickly.
- Data-driven diagnostics: It's important to analyze deliverability data broadly, not just attribute problems solely to the domain switch. A general email delivery problem could be at play.
Marketer view
Marketer from Email Geeks explains they recently switched to private domains in Salesforce Marketing Cloud to apply authentication like DKIM, SPF, and DMARC. However, they are experiencing worse deliverability than before, with messages not landing in inboxes.
Marketer view
Marketer from Email Geeks states that their definition of "worse" deliverability includes increased anecdotal reports of messages going to spam, a 40% lower open rate year-over-year, and significant revenue deltas from their campaigns.
What the experts say
Email deliverability experts strongly emphasize that any new sending domain or subdomain, regardless of whether it's on a dedicated or shared IP, requires a proper warming process. The assumption that SFMC's 'private domain' setup automatically handles reputation for new domains is a common misconception that leads to significant deliverability problems. Experts advocate for a strategic approach that involves gradually increasing volume to highly engaged segments, potentially even temporarily reverting to a known good domain, and understanding the nuanced relationship between root domain and subdomain reputations. Additionally, advanced techniques like DKIM double-signing can be considered to smoothly transition domain reputation.
Key opinions
- Warmup is non-negotiable: Experts agree that domain warmup is essential for any new sending domain or subdomain, including those in SFMC's private domain setup, even if the IP is shared. Warming a new domain on an existing warmed IP is still critical.
- Reputation hierarchy: Subdomain reputation contributes to the root domain's reputation, and vice versa, meaning issues on one can affect the other, though they are somewhat separate.
- Pre-fetching impact: A drop in observed open rates might be partly due to Google stopping email pre-fetching with new authentication, which can make deliverability appear worse than it is, though actual spam placement is a more serious indicator.
- Strategic re-engagement: Sending to the most engaged users first helps train ISPs that the mail is wanted, encouraging them to deliver to the inbox even if initially flagged as bulk/spam.
Key considerations
- Temporary old domain use: Consider reverting to the old, warmed domain for a short period (1-2 weeks) to stabilize critical sends, then commence a structured warmup for the new domain. This aligns with best practices for subdomain warmups.
- DKIM double signing: If the ESP allows, implementing a "stealth" warmup by double signing outgoing mail with both the old and new DKIM signatures can help introduce the new subdomain's reputation gradually.
- Comprehensive analysis: Problems might stem from broader delivery issues, not just the domain switch. A holistic review of sending practices is often needed to master email deliverability in Marketing Cloud.
- Warmup scope: Remember to warm IPs, domains, and the specific domain-on-IP combination to ensure optimal deliverability.
Expert view
Expert from Email Geeks suggests that the observed deliverability issues are likely standard warmup problems common to newly seen domains. They acknowledge the complexity of the private versus public domain distinction but indicate it points to a common reputation challenge.
Expert view
Expert from Email Geeks advises against removing authentication to ensure inbox placement. They assert that working on sender reputation is the best path forward, as authentication is now a baseline requirement for deliverability.
What the documentation says
Official documentation from leading ESPs and industry bodies consistently underscores the importance of domain warming as a distinct process from IP warming or simple domain authentication. While Salesforce Marketing Cloud's Sender Authentication Package (SAP) configures your domain with SPF, DKIM, and DMARC, it primarily establishes technical trust and branding, not a pre-built sending reputation. Documentation often outlines gradual send volume increases to highly engaged subscribers as the fundamental method for building positive domain reputation with Internet Service Providers (ISPs), highlighting that skipping this step, particularly for new subdomains, inevitably leads to deliverability challenges like blocklisting and filtering to spam folders.
Key findings
- Authentication setup: The Sender Authentication Package (SAP) in Salesforce Marketing Cloud is designed to configure your domain for SPF, DKIM, and DMARC, making your emails trustworthy in terms of origin. For details on SPF, DKIM, and DMARC, refer to our guides.
- Reputation building: Authentication is a prerequisite, not a replacement, for building a positive sending reputation. This reputation is built over time based on recipient engagement, spam complaint rates, and bounces.
- Warming procedure: Documentation emphasizes that warming involves sending increasing volumes of mail to a highly engaged audience to demonstrate consistent, desired sending behavior to ISPs.
- Domain vs. IP warmup: While often discussed together, domain and IP warmups are distinct. A new domain, even on an established IP, must build its own reputation. For more on warming a dedicated IP and domain, consult our guide.
Key considerations
- Gradual ramp-up: Always follow a phased approach for warming, starting with low volumes to highly engaged segments and slowly increasing volume and audience breadth. The Salesforce Ben guide on email authentication stresses this implicitly.
- Monitor engagement metrics: Pay close attention to opens, clicks, and especially spam complaints. High complaints on a new domain can quickly lead to blocklists and blacklists.
- List hygiene: Clean lists are crucial, especially during warmup. Sending to unengaged or old contacts can trigger spam traps and damage reputation. Consider understanding your email domain reputation.
- Patience and consistency: Building domain reputation takes time and consistent, positive sending. There are no quick fixes for a damaged reputation.
Technical article
Documentation from Salesforce Trailhead states that establishing credibility and increasing deliverability for new senders necessitates initiating an IP and domain warming process. This procedure is fundamental for building a positive relationship with receiving email servers.
Technical article
Salesforce Ben documentation highlights that a key step when setting up Marketing Cloud email deliverability involves configuring your Sender Authentication Package (SAP). This initial setup establishes the technical foundation for sending, but does not substitute for reputation building.
Related resources
9 resources
Related pages
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