Summary
While opinions vary, the overall consensus indicates that domain warmup is beneficial, even for small email lists. Experts and documentation emphasize the importance of gradually increasing sending volume, starting with engaged subscribers, and closely monitoring deliverability. Some sources suggest that a full-scale warmup may not be necessary for very small lists (under a few hundred), particularly if the domain is older than 30 days. However, adhering to best practices for bulk sending, such as domain authentication and avoiding sudden spikes in volume, remains crucial. Building a positive sender reputation is consistently highlighted as a key factor in achieving successful email deliverability.
Key findings
- Gradual Ramp-Up: Gradual increase in sending volume is consistently recommended across various sources.
- Engaged Subscribers: Starting with highly engaged subscribers helps build a positive sender reputation.
- Monitor Deliverability: Regularly monitoring deliverability metrics is essential for identifying and addressing potential issues.
- Domain Authentication: Domain authentication (SPF, DKIM, DMARC) is crucial for establishing trust and improving deliverability.
- Build Reputation: Building a positive sending reputation is paramount for successful email delivery, regardless of list size.
Key considerations
- List Size: The necessity of a full-scale warmup depends on list size; smaller lists may require a less aggressive approach.
- Domain Age: Newer domains generally require more diligent warming strategies than older domains.
- Volume Spikes: Avoid sudden spikes in sending volume, as they can trigger spam filters, even with small lists.
- Content Quality: Focus on sending high-quality, engaging content to minimize spam complaints and maximize engagement.
- Whitelisting: Consider implementing a whitelisting campaign to encourage recipients to add your domain to their address books.
What email marketers say
10 marketer opinions
While opinions vary, the general consensus is that warming up a new domain is beneficial, even for small email lists (under 500 subscribers). Although a full-scale warm-up might not be necessary, gradually increasing sending volume, starting with engaged subscribers, and monitoring deliverability are recommended to build a positive sender reputation and avoid spam filters.
Key opinions
- Gradual Increase: Gradually increasing sending volume is a common recommendation to establish a positive sender reputation.
- Engaged Subscribers First: Starting with your most engaged subscribers is recommended to build trust with ISPs.
- Monitor Deliverability: Closely monitoring deliverability is important to identify and address any issues early on.
- Whitelisting Campaign: Sending a whitelisting campaign can help improve deliverability.
- Domain Reputation: Establishing a domain reputation is important regardless of list size.
Key considerations
- List Size: The necessity of a full-scale warm-up might depend on the size of your email list.
- Content Quality: Focus on sending high-quality, engaging content to avoid spam complaints.
- Authentication: Ensure proper domain authentication (SPF, DKIM, DMARC) is in place.
- Engagement Metrics: Watch engagement rates (opens, clicks) and bounce rates to assess deliverability.
- Personalization: Sending personalized emails to engaged subscribers first can establish a positive reputation.
Marketer view
Email marketer from GlockApps recommends that even with a small list, you should gradually increase your sending volume. Start by sending to highly engaged users and closely monitor your deliverability to catch any issues early.
25 Nov 2023 - GlockApps
Marketer view
Email marketer from Litmus suggests that domain warmup is essential, even with smaller lists. Always authenticate and start with lower volumes. Watch engagement and bounce rates, adjusting based on the data.
11 Mar 2025 - Litmus
What the experts say
8 expert opinions
Experts offer varied perspectives. Some suggest domain warming is unnecessary for small lists (under a few hundred) unless the domain is brand new (less than 30 days). Others recommend gradual ramp-up, even for small lists, to build sender reputation and avoid triggering spam filters. Ensuring proper domain setup (MX records, website) is consistently emphasized. The consensus leans towards warming becoming crucial for sending volumes in the thousands.
Key opinions
- Small Lists, Less Need: For very small lists (e.g., 100 or fewer), domain warming may not be required, especially if the domain is not new.
- Gradual Ramp-Up Advised: A gradual increase in sending volume is recommended, even for small lists, to establish a positive sender reputation.
- Large Lists Require Warming: When sending to thousands of recipients, domain warming becomes essential.
- Domain Setup Crucial: Ensuring proper domain configuration (MX records, website) is always necessary.
Key considerations
- Domain Age: Consider the age of the domain; newer domains require more careful warming.
- List Size Threshold: Determine the list size at which domain warming becomes a significant factor (opinions range from hundreds to thousands).
- Engagement: Begin sending to your most engaged subscribers to build a positive reputation.
- Spam Filters: Be aware that sudden volume increases, even on small lists, can trigger spam filters.
Expert view
Expert from Email Geeks explains that unless the domain is less than 30 days old, sending to 100 people won't require warming at all.
26 Dec 2024 - Email Geeks
Expert view
Expert from Spamresource explains that domain warmup is recommended even for a smaller list to build a reputation.
1 Mar 2023 - Spamresource
What the documentation says
5 technical articles
Documentation from various sources including Google, Microsoft, RFC-Editor, SparkPost (MessageBird), and AWS emphasizes that even when sending to a small email list from a new domain, adopting warming practices is crucial. This includes gradually increasing sending volume over time, adhering to best practices for bulk sending such as proper authentication, and building a positive sending reputation to improve deliverability and avoid spam filters. Although some documentation is focused on IP warming, the principles are considered equally valid for domain warming.
Key findings
- Gradual Volume Increase: Gradually increasing sending volume is essential for establishing trust and a positive sending reputation, even for small lists.
- Authentication: Adhering to best practices for bulk sending, like authenticating your domain (SPF, DKIM, DMARC), is critical for deliverability.
- Avoid Sudden Spikes: Avoiding sudden spikes in sending volume helps prevent triggering spam filters.
- Applies to Domains: IP warming principles are applicable and equally valid for domain warming strategies.
Key considerations
- Best Practices: Implement best practices for bulk sending regardless of list size.
- Reputation Building: Focus on building and maintaining a positive sending reputation from the start.
- Monitoring: Closely monitor deliverability metrics to identify and address potential issues promptly.
- All New Domains: These practices apply to all new sending domains, even with initially low sending volumes.
Technical article
Documentation from RFC-Editor explains that gradually increasing the sending volume from a new domain is a best practice for SMTP. This helps establish trust with receiving mail servers, even if you're only sending to a small list initially.
30 Jul 2021 - RFC-Editor
Technical article
Documentation from AWS responds that for all new sending domains (even for low volumes), monitoring closely and building a good reputation is key for deliverability success, following the same practices as a warm up.
28 Jul 2021 - AWS
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