What is the best approach for sending marketing emails from a new domain for an existing company?
Matthew Whittaker
Co-founder & CTO, Suped
Published 12 Aug 2025
Updated 16 Aug 2025
7 min read
When an existing company decides to launch a new service, it's natural to consider how best to handle its marketing email strategy. A common question that arises is whether to continue sending from the established main domain or to set up a brand-new domain specifically for the new offering. This decision has significant implications for email deliverability and overall brand perception.
The core motivation behind using a new domain for a separate service is often to isolate sender reputation. If issues arise with marketing emails for the new service, such as high unsubscribe rates, spam complaints, or even being added to an email blacklist (or blocklist), the goal is to prevent these problems from affecting the deliverability of emails sent from the main company domain.
Achieving this isolation, while maintaining strong deliverability for both domains, requires a thoughtful and strategic approach. This includes careful consideration of domain setup, IP strategy, and a robust warming plan.
Why consider a new domain for marketing emails?
Using a separate domain for marketing emails, especially for a distinct service offering, can be a highly effective strategy for protecting your primary brand's email reputation. It creates a clear separation in the eyes of mailbox providers (MBPs) and recipients.
If a marketing campaign for the new service experiences higher-than-usual complaint rates or is flagged as spam, the impact is confined to the new domain. This prevents any negative reputation spillover to your main corporate or transactional email domain, which is crucial for business-critical communications. Without this separation, issues with marketing emails could jeopardize important operational emails, such as password resets or order confirmations.
Moreover, separating domains allows for more targeted content. Subscribers interested in one service might not be interested in another, leading to different engagement patterns. By using distinct domains, you can better manage unsubscribe requests and tailor content to specific audience segments without alienating your entire subscriber base.
Setting up your new domain for success
Once the decision to use a new domain is made, the initial setup is critical. This involves registering a new domain that aligns with the new service's branding and choosing a reliable email service provider (ESP) or setting up your own mail server, depending on your volume and control needs. For existing companies, leveraging your current ESP's capabilities for a new domain is often the most straightforward path.
The absolute first step, even before sending your first email, is to ensure proper domain authentication. This includes configuring Sender Policy Framework (SPF), DomainKeys Identified Mail (DKIM), and Domain-based Message Authentication, Reporting, and Conformance (DMARC) records. These protocols verify that your emails are legitimate and prevent spoofing, significantly impacting your email deliverability. Mailbox providers like Google and Yahoo require these to ensure your emails reach the inbox.
Essential authentication records
Properly setting up SPF, DKIM, and DMARC is non-negotiable for any new sending domain. Without them, your emails are highly likely to land in spam folders or be rejected outright.
SPF:A TXT record that specifies which mail servers are authorized to send email on behalf of your domain. Only one SPF record per domain is allowed.
DKIM:A digital signature that allows the recipient's server to verify that the email was indeed sent by the domain owner and that the content hasn't been tampered with. Your ESP typically provides the DKIM record.
DMARC:Builds on SPF and DKIM by instructing receiving mail servers how to handle emails that fail authentication and provides reporting. Start with a p=none policy to monitor first.
SPF Record ExampleDNS
v=spf1 include:_spf.example.com ~all
DKIM Record ExampleDNS
k1._domainkey.example.com. IN TXT "v=DKIM1; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDnQvUaZ..."
For detailed guidance on setting up these records, review resources on email authentication best practices. Regular monitoring of your DMARC reports will provide insights into your email stream's authentication status and detect potential issues.
Warming up your new sending domain
Warming up a new email domain is absolutely essential, regardless of whether you're using a new IP address or sharing one. It's the process of gradually increasing your email sending volume to build a positive sender reputation with mailbox providers. Starting with a large volume from a brand new domain will likely result in your emails being marked as spam or rejected.
The key is to send small volumes to highly engaged subscribers first. These are recipients who are most likely to open, click, and reply, sending positive signals to MBPs. Gradually increase your sending volume and the diversity of your audience over several weeks, closely monitoring engagement rates and bounce rates. This systematic approach allows MBPs to learn that your new domain sends legitimate, wanted emails.
Day Range
Daily Volume
Engagement Focus
Days 1-3
50-100
Highly engaged, internal lists
Days 4-7
100-500
Most active subscribers
Weeks 2-3
500-2,000
Engaged segments, introduce new contacts gradually
Weeks 4-6+
Scale up to full volume
Monitor all metrics closely, maintain engagement
Regarding IP strategy, for volumes in the 10,000s to 100,000s, a shared IP might suffice initially, especially during the early stages of warming. However, for higher volumes and greater control over your sender reputation, a dedicated IP is generally recommended. A dedicated IP allows you to build your own reputation from scratch, which can be beneficial in the long run. If you are starting on a new dedicated IP, it will also need to be warmed up in conjunction with the new domain. For more information, check out how to warm up a new sending domain. An important resource for Google's email sender guidelines also provides essential information.
Shared IP address
Using a shared IP means your email traffic is mixed with other senders. This can be beneficial for lower volumes as the shared reputation provides some initial stability.
Pros: Lower cost, easier management, built-in warming by ESP.
Cons: Your reputation can be affected by other senders' poor practices.
Dedicated IP address
A dedicated IP gives you full control over your sending reputation. It requires a significant warm-up period to build trust with MBPs.
Pros: Complete control over reputation, better for high volumes.
Cons:Requires a strategic warm-up plan, higher maintenance.
Beyond technical setup, content quality and audience engagement are paramount during warm-up. Send valuable, relevant content to your most active subscribers. Avoid sending to old, unengaged lists. High engagement signals positive sender behavior to MBPs, accelerating the warm-up process. It’s better to send fewer emails that are opened and clicked than many that are ignored or marked as spam.
Maintaining ongoing sender reputation
Warming up a domain is not a one-time event, but rather the initial phase of ongoing sender reputation management. After successfully warming your new domain, continuous monitoring and adherence to best practices are crucial for maintaining strong deliverability.
This involves regularly cleaning your email lists, removing inactive subscribers, and promptly processing unsubscribe requests. Consistent sending volume and frequency, coupled with engaging content, will help sustain a positive sender reputation. Additionally, pay close attention to your domain reputation metrics through tools like Google Postmaster Tools and DMARC reports.
Being proactive about list hygiene and managing subscriber expectations through clear preference centers helps minimize complaints and avoid being listed on a blocklist (or blacklist). Maintaining a healthy sending domain is an ongoing commitment to deliverability success.
Views from the trenches
Best practices
Always prioritize building a separate, positive sender reputation for the new domain from day one.
Implement strong email authentication (SPF, DKIM, DMARC) immediately to establish trust with mailbox providers.
Gradually increase sending volume to highly engaged segments during the warming phase.
Maintain consistent sending patterns and list hygiene to sustain long-term deliverability.
Common pitfalls
Sending large volumes from a brand new domain without a proper warm-up strategy.
Failing to set up or incorrectly configuring email authentication records.
Assuming that a new domain instantly inherits the reputation of an existing company's main domain.
Ignoring engagement metrics (opens, clicks, complaints) during the warming and ongoing sending phases.
Expert tips
If volumes are initially low (e.g., thousands), starting with a shared IP range from a reputable ESP can be more effective before transitioning to dedicated IPs.
Ensure your marketing emails, even from a new domain, consistently reinforce the main company's branding to avoid recipient confusion.
Regularly monitor DMARC reports for insights into your email stream's authentication and deliverability performance.
Content relevance is key. If unsubscribes are high, it often signals a mismatch between content and subscriber interest, not necessarily an IP or domain issue.
Marketer view
Marketer from Email Geeks says that the concern about unsubscribes from one domain not impacting the other can sometimes indicate a focus on quantity over quality, which means the client might need coaching on direct opt-in consent and targeting.
2021-09-17 - Email Geeks
Expert view
Expert from Email Geeks says that unsubscribes are not primarily a function of the IP address or reputation. The use of separate IPs often relates to branding efforts, keeping different brand mail streams distinct.
2021-09-17 - Email Geeks
Building a solid foundation for new email initiatives
Launching a new service with its own marketing email domain for an existing company is a strategic move that, when executed correctly, can safeguard your primary domain's reputation and enhance brand differentiation. The process demands meticulous attention to detail, particularly in terms of domain authentication, IP selection, and a well-structured warming plan.
By prioritizing reputation isolation, implementing robust authentication from day one, and diligently warming your new domain with engaged audiences, you lay a strong foundation for long-term deliverability success. Remember that email deliverability is an ongoing effort, requiring continuous monitoring and adaptation to maintain a healthy sender reputation across all your domains. This approach ensures your marketing messages consistently reach the inbox, supporting the growth of both your new service and existing company offerings.
Requires a strategic warm-up plan, higher maintenance.
