Is a dedicated IP address suitable for a compliant sender with a weekly sending pattern of 1M+ emails, and how should it be warmed up?
Michael Ko
Co-founder & CEO, Suped
Published 26 Jul 2025
Updated 19 Aug 2025
7 min read
When managing large-volume email campaigns, especially those exceeding one million emails weekly, the choice between a shared and dedicated IP address is a critical decision. While a shared IP might seem appealing for its immediate ease of use, a dedicated IP address offers far greater control and long-term stability for your sender reputation. The primary concern with a weekly sending pattern, however, is maintaining a consistent reputation with internet service providers (ISPs) despite the periods of inactivity between sends and the large volume spikes.
A compliant sender, meaning one who adheres to email best practices, has proper authentication, and sends to engaged recipients, is generally well-suited for a dedicated IP. This is because a dedicated IP allows you to build a specific reputation tied solely to your sending practices. If you maintain low bounce rates, high engagement, and minimal spam complaints, your dedicated IP's reputation will reflect that positively, leading to better inbox placement.
The challenge with a weekly sending pattern of 1M+ emails lies in the potential for IP reputation to decay during the week when no emails are sent. ISPs continuously monitor sending behavior. A sudden surge after days of quiet can sometimes trigger filters if not managed properly. However, it's certainly manageable with a strategic approach to warming up the IP and consistent list hygiene.
Warming up your dedicated IP
The initial warm-up phase for a dedicated IP is crucial, regardless of your long-term sending frequency. This process involves gradually increasing your email volume over several weeks to build a positive sending history and establish trust with major ISPs. The goal is to show ISPs that you are a legitimate sender with consistent sending patterns and good engagement rates. Skipping or rushing this phase can lead to your emails being flagged as spam, bounced, or even result in your IP being placed on a blocklist (or blacklist).
It typically takes 4-8 weeks to achieve maximum deliverability, depending on your volume and the level of engagement you receive. Mailbox providers assess your sending reputation based on various factors, including spam complaints, bounce rates, and recipient engagement. Therefore, a careful and consistent warm-up is essential. For more general information about this process, you can explore guides on what is the best IP warmup strategy.
When warming up a dedicated IP for a weekly 1M+ email sender, the key is to prioritize daily sends during the warm-up period, even if your normal sending pattern is weekly. Reputation is built on consistent, positive interactions. Spreading your initial sends across more days will build trust faster than large, infrequent bursts. Once sufficient reputation is established, you can transition to your weekly schedule. The goal during warm-up is to send around 1,000 emails every day to each major email provider to build and maintain a positive reputation, as recommended by Amazon SES documentation on dedicated IP warming.
Warm-up approach for weekly senders
Standard warm-up process
Gradual increase: Start with very small volumes, ideally to your most engaged segments, and gradually increase the volume daily. This allows ISPs to see positive engagement early on.
Daily consistency: During the warm-up, aim for daily sends, even if they are small. This helps maintain a constant sending signal to ISPs, which is crucial for building a stable reputation.
Target engaged users: Send to your most active subscribers first. Their high open and click rates will significantly boost your new IP's reputation.
The primary goal during the warm-up period is to achieve a consistent daily volume, even if it deviates from your ultimate weekly sending pattern. This helps establish trust. Think of it like building credit history: regular, small, positive transactions build trust faster than one massive, infrequent transaction. Once your IP has a solid reputation, the weekly 1M+ volume becomes sustainable. You can find more detailed information on best practices and schedules for IP warm-up.
After the initial warm-up, when you transition to your weekly sending schedule, maintaining your reputation requires careful attention. Even with a good warm-up, large weekly spikes can sometimes cause temporary filtering issues if ISPs don't see a consistent baseline of activity throughout the week. While IP reputation generally takes 30+ days to fade, as some experts note, consistent, positive signals are always best. Consider if your email sending platform can help manage the daily flow or if you need to adjust your strategy to include small daily sends on non-campaign days, perhaps for transactional emails or highly engaged segments.
Scenario 1: Daily Sending Warm-up
Approach: Distribute the initial 1M+ emails over several days or weeks, gradually increasing volume daily until the desired weekly volume is reached.
Benefits: Builds IP reputation faster, smoother acceptance by ISPs, lower risk of being flagged.
Considerations: Requires temporary adjustment of sending patterns during warm-up, potentially delaying full volume weekly sends for a few weeks.
Maintaining reputation after warm-up
To maintain a healthy sender reputation, consistent positive engagement is key. For a weekly sender, this means ensuring the emails sent are highly relevant and desired by the recipients. Pay close attention to your engagement metrics, such as open rates, click-through rates, and, importantly, complaint rates. High complaint rates or low engagement can quickly damage your IP's standing, even on a dedicated IP. Utilize tools like Google Postmaster Tools and other postmaster tools from major ISPs (like Yahoo and Microsoft) to monitor your reputation and identify any potential issues early on.
Regular list hygiene is paramount. Remove inactive subscribers and hard bounces regularly to prevent sending to addresses that no longer engage or are invalid. This practice minimizes bounce rates and reduces the likelihood of hitting spam traps, which can severely harm your reputation and lead to your IP being listed on a blocklist. Consider reviewing your blocklist checker results often.
Implementing strong email authentication, such as DMARC, SPF, and DKIM, is non-negotiable for any compliant sender. These protocols prove to receiving mail servers that your emails are legitimate and prevent malicious actors from spoofing your domain, protecting your sender reputation. DMARC, in particular, provides valuable feedback on authentication failures, which can help you quickly identify and fix issues. Make sure your DMARC monitoring is set up correctly.
Dedicated IP for high volume weekly sends
Dedicated IP addresses are typically recommended for senders with stable, high-volume email flows. However, even with a weekly 1M+ volume, a dedicated IP can be highly suitable for a compliant sender. The main consideration is managing the 'cold' periods between sends to prevent reputation decay. This can often be mitigated by maintaining very clean lists and consistent sending behavior during your peak send times. For businesses looking at how many IPs are required for email volume, this is an important consideration.
Dedicated IP vs. Shared IP
Aspect
Shared IP
Dedicated IP
Reputation Control
Shared with other senders; reputation is influenced by their practices, potentially leading to deliverability issues from bad actors. Harder to recover if blacklisted.
Full control over your reputation; your sending practices directly impact deliverability. Easier to identify and fix issues if your IP gets on a blocklist or blacklist.
Warm-up Required
Generally less intensive, as the IP is already 'warmed' by others' sends. However, a new sender on a shared IP still needs to build domain reputation.
Mandatory and critical. Requires a structured, gradual increase in volume over several weeks to establish trust with ISPs.
Volume Spikes
High volume spikes on a shared IP can negatively impact other users on that IP, or lead to your emails being throttled by ISPs.
Better suited for managing large volume spikes once warmed, as the IP's capacity and reputation are built to handle your specific volume.
Cost/Complexity
Often included with basic sending plans; simpler setup.
Higher cost and requires active management during warm-up and ongoing monitoring.
Ultimately, for a compliant sender with a weekly volume of 1M+ emails, a dedicated IP is indeed a suitable choice, but it comes with the responsibility of a meticulous warm-up strategy and continuous reputation management. The upfront effort in warming up the IP by spreading out sends will pay dividends in long-term deliverability and consistent inbox placement. Neglecting these aspects can lead to significant deliverability issues, making it harder for your compliant emails to reach their intended recipients.
Monitoring your deliverability is a continuous process. Regular checks of your sender reputation, bounce rates, and complaint rates are essential. Tools and services that offer insight into your email performance and provide early warnings about potential issues can be invaluable. This proactive approach helps in addressing issues before they escalate, ensuring your weekly campaigns consistently land in the inbox.
Conclusion
For a compliant sender with a weekly volume exceeding 1 million emails, a dedicated IP is definitely suitable, provided a robust warm-up strategy is employed. The key is to manage the reputation impact of weekly spikes and periods of inactivity. A dedicated IP offers unparalleled control over your sender reputation, which is crucial for high-volume senders. By carefully executing the warm-up, spreading initial sends, and maintaining stellar email practices, you can ensure your large weekly campaigns consistently achieve high deliverability rates. Remember, consistency and engagement are your best allies in maintaining a healthy sending reputation.
Views from the trenches
Best practices
Implement a structured warm-up schedule with daily sending for several weeks.
Prioritize sending to your most engaged subscribers during the warm-up period to build positive signals.
Continuously monitor engagement metrics, complaint rates, and bounce rates to maintain a healthy sender reputation.
Regularly clean your email list by removing inactive subscribers and hard bounces.
Common pitfalls
Skipping or rushing the IP warm-up process, which can lead to immediate blocklisting or heavy filtering.
Sending large, inconsistent volumes without proper warm-up, confusing ISPs and flagging your mail as suspicious.
Neglecting list hygiene, leading to high bounce rates and spam trap hits, damaging IP reputation.
Ignoring feedback loops and DMARC reports, missing critical insights into deliverability issues.
Expert tips
For weekly senders at high volume, warm up the IP by spreading out sends daily initially to build reputation faster, then transition to weekly.
IP reputation generally takes 30+ days to fade, so consistent positive signals are more important than daily volume during the entire week once warmed up.
Many large senders successfully manage weekly sends on dedicated IPs by maintaining a highly engaged list and strong sender compliance.
Focus on the number of sends during warm-up, not just the time period. More consistent sends across days help build reputation more quickly.
Expert view
Expert from Email Geeks says a weekly sender at that volume is a fine candidate for a dedicated IP.
2024-05-07 - Email Geeks
Expert view
Expert from Email Geeks says IP reputation generally takes 30 or more days to fade.
Microsoft) to monitor your reputation and identify any potential issues early on.
