What is the best approach to warm up a new domain after a rebrand while keeping the same IP address?
Matthew Whittaker
Co-founder & CTO, Suped
Published 26 May 2025
Updated 16 Aug 2025
7 min read
Rebranding is an exciting venture, but when it comes to email deliverability, it introduces a unique set of challenges. One common scenario is moving to a completely new sending domain while retaining your existing, already warmed-up IP address. Many assume that because the IP is warm, the domain transition will be swift, perhaps even less than a week. However, this assumption can lead to significant deliverability issues if not approached with caution and a clear strategy.
While your IP address carries its own reputation, mailbox providers also heavily weigh the reputation of your sending domain. A new domain is, by definition, an unknown entity to them, regardless of the IP it's associated with. This means it lacks the historical data email providers rely on to trust incoming mail, requiring a careful warm-up process to build that credibility.
Why domain warming matters, even with a warm IP
Even if your IP address has a stellar reputation, a new domain introduces an element of uncertainty for Internet Service Providers (ISPs) and mailbox providers (MBPs). They perceive this new domain as a distinct sending identity, and without a history of positive sending behavior, it's treated with suspicion. This is particularly true for major providers like Gmail, which place significant emphasis on domain reputation as a primary indicator of trust. You can find more information on domain versus IP warming in this article on IP warm-up vs. domain warm-up.
The existing IP's good standing will help somewhat, but it's not a silver bullet. Think of it like a trusted delivery truck getting a new company logo. The truck (IP) is known, but the new company (domain) still needs to prove its reliability and trustworthiness before deliveries (emails) are fully accepted without scrutiny. This is why you must still adhere to best practices for warming a new sending domain on an existing warm IP address.
Without proper domain warming, even mail sent from a seasoned IP can land in the spam folder or be outright rejected. ISPs prioritize sender reputation and will flag emails from new, unestablished domains as potential spam or phishing attempts. This can quickly lead to your new domain being placed on email blacklists (or blocklists), severely impacting your deliverability.
Key considerations for your rebrand warm-up
A successful domain warm-up after a rebrand hinges on several critical factors. The goal is to gradually introduce your new domain to mailbox providers, building trust over time. This involves more than just sending emails, but also setting the stage for success.
First, consider the age of your new domain. It's beneficial to let a new domain exist for a period, ideally 30-60 days, before you even begin the warming process. This aging period helps establish legitimacy in the eyes of ISPs. During this time, ensure all necessary email authentication records (SPF, DKIM, DMARC) are correctly configured for your new domain. This sets a strong foundation for your sending reputation.
Another crucial step is communicating your rebrand to your audience. Inform them about the new domain and what to expect. This proactive communication can mitigate complaints and unsubs due to unfamiliarity, which could negatively impact your new domain's reputation. Klaviyo offers helpful insights on how to change your domain name during a rebrand while maintaining good deliverability.
Strategies for a smooth domain transition
The core of domain warm-up is a gradual increase in sending volume to highly engaged recipients. This teaches mailbox providers that your new domain sends desired mail.
Start small: Begin by sending very low volumes (e.g., 5-10 emails) to your most engaged subscribers. These are contacts who reliably open and click your emails. Gradually increase the volume and segment size over several weeks or months. ActiveCampaign provides best practices for slowly warming up a new sending domain.
Monitor engagement metrics: Keep a close eye on your open rates, click-through rates, and, crucially, your spam complaint rates. High engagement signals positive reputation, while spikes in complaints can quickly lead to blocklists (or blacklists) and poor inbox placement.
Utilize feedback loops: Sign up for feedback loops (FBLs) with major ISPs. These notify you when subscribers mark your emails as spam, allowing you to remove those recipients from your list and protect your new domain's reputation. Learn more about Google Postmaster Tools to monitor your domain and IP reputation.
Remember that consistency is key. Err on the side of caution and patience. A slow and steady approach will build a robust reputation for your new domain, ensuring long-term deliverability success.
Understanding the difference
IP warm-up
Primarily focuses on establishing the reputation of the sending IP address.
Timeline: Typically weeks to months, depending on volume.
Focus: Builds trust in the physical server sending emails.
Domain warm-up with same IP
Focuses on establishing the reputation of the new sending domain, even if the IP is known.
Timeline: Weeks, potentially a month or more for high volumes. The EmailLabs guide to email warm-up suggests gradually shifting traffic to the new domain.
Focus: Builds trust in the brand identity associated with the email.
Realistic timelines for domain warming
The idea that a domain warm-up when keeping the same IP can be completed in less than a week is generally unrealistic for a truly new domain. While it might be faster than a full IP warm-up from scratch, it still demands patience. Domain reputation builds through consistent, positive sending behavior over time. The Customer.io article on rebranding also advises treating a new domain like a new IP.
Expect a warm-up period of at least a month, and potentially longer, especially if your sending volumes are high or your audience is highly diverse. Mailbox providers assess reputation based on various timeframes: 24-hour, 3-day, 7-day, 30-day, and even 90-day trends. A rapid spike in volume from a new domain, even with a warm IP, can trigger spam filters and lead to a swift decline in your sending reputation.
If your new domain was previously used and already had a positive sending history (a warm domain), the warm-up period might be abbreviated. In this specific case, the goal is to help machine learning filters associate its established reputation with the new IP/domain combination. However, if the new domain is truly fresh, plan for a comprehensive warm-up akin to that of a brand-new IP address. This helps ensure your IP warmup strategy for a new domain on an existing IP is effective.
Views from the trenches
Best practices
Ensure your new domain has been registered and 'aged' for at least 30-60 days before you begin sending.
Proactively inform your audience about the domain change to prevent confusion and unsubscribes.
Start your sending with extremely low volumes to your most engaged subscribers, slowly increasing over time.
Rigorous monitoring of deliverability metrics (opens, clicks, complaints) is essential throughout the process.
Common pitfalls
Assuming a domain warm-up is significantly faster than an IP warm-up, especially for a truly new domain.
Sending high email volumes too quickly to your entire list, risking immediate reputation damage.
Neglecting to properly configure all DNS records (SPF, DKIM, DMARC) for the new domain.
Failing to adapt your warm-up schedule based on recipient engagement and mailbox provider feedback.
Expert tips
Treat a new domain with the same warm-up rigor as a new IP, focusing on incremental volume increases.
Understand that domain reputation is multi-faceted and built over time through consistent, positive sending behavior.
If migrating an already warm domain, the warm-up can be abbreviated to help machine learning filters re-associate trust.
Patience is paramount. Hasty warm-up attempts are a leading cause of deliverability problems.
Marketer view
Marketer from Email Geeks says letting a new domain exist for 30-60 days before starting the warming process is beneficial, especially for Gmail, which considers the sending domain a significant identity indicator.
February 10, 2023 - Email Geeks
Marketer view
Marketer from Email Geeks says that warming up a new domain is typically as slow and lengthy as warming an IP address, and rushing this process often leads to deliverability issues.
February 10, 2023 - Email Geeks
The path to deliverability after a rebrand
While rebranding is a strategic move, don't let the excitement overshadow the critical need for a proper domain warm-up. Keeping the same IP address provides some advantage, but it doesn't negate the necessity of building a new reputation for your domain from the ground up.
Patience, meticulous planning, and diligent monitoring are your greatest allies. By treating your new domain with the respect it deserves, you can ensure a smooth transition, maintain high deliverability rates, and protect your sender reputation in the long run. If you want to check your email deliverability rates, you can use our free email deliverability tester.
Gmail, which place significant emphasis on domain reputation as a primary indicator of trust. You can find more information on domain versus IP warming in this article on IP warm-up vs. domain warm-up.
