Summary
For email senders with inconsistent, high-volume campaigns, the choice between dedicated and shared IPs is critical for deliverability. While dedicated IPs offer full control over reputation, they require consistent sending to maintain a positive standing with Internet Service Providers (ISPs). Inconsistent large sends, such as once a month or quarterly, can lead to reputation degradation on a dedicated IP due to the lack of continuous volume. Shared IPs, managed by an Email Service Provider (ESP), are often better suited for sporadic high-volume sends because the overall activity from other senders helps keep the IP warm and distribute the sending load.
Key findings
- Inconsistent volume: Dedicated IPs thrive on consistent volume. Sporadic, large bursts can negatively impact reputation.
- Shared IP benefit: Shared IPs mitigate the impact of inconsistent sending by leveraging collective volume for warming and reputation.
- Hybrid approach: Many senders use dedicated IPs for regular volume and shared IPs for infrequent, massive campaigns.
- IP warming concerns: A dedicated IP for inconsistent sending means needing to re-warm or re-establish reputation with each large send.
- Deliverability stability: Shared pools provide more stable deliverability for inconsistent senders due to continuous traffic.
Key considerations
- Reputation management: Consider the long-term impact on your sender reputation. Inconsistent volume can lead to deliverability degradation.
- Volume thresholds: Assess what email volume justifies a dedicated IP. Smaller, inconsistent sends might benefit more from shared IPs.
- ISP perception: ISPs (Internet Service Providers) track sending patterns. Sudden large volume after dormancy can trigger spam filters.
- Shared IP risks: While good for inconsistency, shared IPs carry the risk of others' bad sending affecting your deliverability. Learn more about dedicated vs. shared IPs.
- ESP guidance: Consult your Email Service Provider about their recommendations for your specific sending pattern. They often have tailored advice on when to use a shared IP.
What email marketers say
Email marketers often face challenges with inconsistent, high-volume sending. The general sentiment suggests that for truly sporadic campaigns of millions of emails, shared IPs (or a hybrid strategy) can be more effective than dedicated IPs. This is because shared pools maintain consistent traffic, which helps mitigate the negative impact of long periods of inactivity from a single sender. While some marketers might prefer the control of a dedicated IP, the reality of inconsistent large sends often points to the advantages of a well-maintained shared environment provided by an ESP.
Key opinions
- Shared IPs for large, infrequent sends: Marketers frequently advocate for shared IP pools when dealing with massive, quarterly, or semi-annual email deployments.
- Dedicated IPs for consistent daily volume: For senders with regular, high-volume needs (e.g., millions daily), dedicated IPs are the preferred choice.
- Volume concentration: Even large, inconsistent sends of 1-2 million can benefit from shared pools.
- Batching considerations: For extremely large, inconsistent sends, batching over several days may or may not be necessary depending on the ESP and pool.
Key considerations
- Hybrid strategy effectiveness: Using both dedicated and shared IPs allows for optimal management of varied sending patterns.
- ISP perception of new or sporadic senders: Sending high volume infrequently from a dedicated IP can look like a new or suspicious sender to ISPs, potentially leading to deliverability issues.
- Maintaining IP reputation: A dedicated IP needs consistent warming. If not, it can be detrimental to your sending reputation, impacting email deliverability.
- Managing large sends: For very large quarterly sends (e.g., 100 million), shared pools can handle the burst without requiring intensive IP warming efforts from the sender. Consider sending large email deployments in batches.
Marketer view
Marketer from Email Geeks asks if a dedicated IP is suitable for inconsistent, high-volume sends, such as 1-2 million emails monthly or bi-monthly, and suggests shared IPs might be more appropriate for such patterns.
Marketer view
Marketer from Zoho Zeptomail states that for low-volume or inconsistent senders, a dedicated IP might actually harm deliverability rather than help it, suggesting shared IPs are generally better.
What the experts say
Experts universally agree that consistency is paramount for maintaining a good sender reputation, especially on a dedicated IP. For inconsistent, high-volume sends, the consensus leans towards utilizing shared IP pools or a hybrid strategy. Dedicated IPs thrive on predictable volume to build and sustain trust with ISPs. A sudden surge after a period of inactivity on a dedicated IP can look suspicious, potentially leading to blocklisting or throttling. Shared IPs, by contrast, smooth out these volume fluctuations, distributing the load and reputation impact across many senders.
Key opinions
- Consistency is king: Dedicated IPs require consistent email volume to maintain a positive sender reputation and inbox placement.
- Inconsistent volume harms dedicated IPs: Spikes after long periods of inactivity on a dedicated IP are detrimental to deliverability.
- Shared IPs for sporadic sends: Shared IP pools are generally better for senders with inconsistent, high-volume needs, as they benefit from the cumulative sending of others.
- Hybrid strategy recommended: Combine dedicated IPs for regular sends with shared IPs for large, infrequent campaigns to optimize deliverability.
Key considerations
- Warm-up challenges: Every large, inconsistent send on a dedicated IP effectively requires a mini-IP warm-up, which can be inefficient and risky for email deliverability.
- Reputation dilution on shared IPs: While shared IPs protect against individual inconsistency, senders should still monitor their lists to avoid contributing to general pool issues. Consider using blocklist monitoring to stay informed.
- Volume guidelines: Generally, if you send less than 100,000 emails per month consistently, a dedicated IP might not be beneficial. For very high but inconsistent volumes, shared pools are safer. Understand what email volume justifies a dedicated IP.
- IP reputation scoring: ISPs assign reputation scores based on sending patterns. Inconsistent sending from a dedicated IP can result in lower trust scores and increased filtering.
Expert view
Expert from Email Geeks explains that dedicated IPs are best for senders with highly consistent daily volumes, as maintaining a steady flow is key to building and preserving a strong reputation.
Expert view
Expert from SpamResource clarifies that inconsistent sending on a dedicated IP often means the IP cools down between campaigns, leading to deliverability challenges with each new burst.
What the documentation says
Email service provider documentation and industry guides frequently underscore the importance of consistent volume for dedicated IP performance. Many resources recommend dedicated IPs primarily for senders who maintain high and predictable email volumes. For senders with inconsistent, high-volume needs, documentation often suggests that shared IPs are a more suitable starting point or a complementary solution. This is because shared IP pools are designed to handle aggregated traffic, absorbing individual sender fluctuations without severe negative impact on overall deliverability.
Key findings
- Dedicated IP criteria: Documentation often defines dedicated IP suitability based on consistent high volume (e.g., >100,000 emails/month).
- Risk of inconsistent dedicated IP: Sending infrequently or with large spikes on a dedicated IP can hinder reputation building and result in poor inbox placement.
- Shared IP resilience: Shared IPs are designed to absorb sending inconsistencies from individual users within a larger pool.
- Reputation isolation vs. sharing: Dedicated IPs isolate reputation, which is beneficial only with good, consistent sending practices.
Key considerations
- Volume thresholds: Ensure your monthly sending volume meets the ESP's recommendations for a dedicated IP to avoid performance issues. Mailgun suggests considering which IP type.
- IP warming requirements: Dedicated IPs require a strategic IP warming process that is difficult to maintain with inconsistent sending. Scaleway documentation provides insights on dedicated IPs.
- Reputation building: A dedicated IP's reputation is built over time with consistent, good sending practices. Inconsistency prevents this.
- Deliverability impact: ISPs value predictability. Inconsistent volume on a dedicated IP can lead to slower delivery or messages being sent to the spam folder.
Technical article
Documentation from Klaviyo generally states that businesses sending high volumes of email should use a dedicated IP infrastructure, implicitly assuming consistency.
Technical article
Documentation from Zoho Blog highlights that dedicated IPs allow high-volume users to isolate and gain full control over their sender reputation, which requires consistent effort.
Related resources
6 resources
Related pages
What are the deliverability risks of volume peaks and dips?
When sending large emails on shared IPs, should I batch?
What email volume justifies using a dedicated IP address?
What is the minimum monthly volume for a dedicated IP?
When should I use a shared IP vs. dedicated IP?
Why your emails fail: expert guide
Email deliverability issues: getting messages to inbox
How your email address ends up on a blacklist
What happens when your IP gets blocklisted?
How to manage inconsistent bulk email sending volume?
