Definition of Shared IP
Shared IP means your newsletter sends from an IP address used by multiple senders through your email service provider. It's like sharing an apartment building's mailing address with other tenants. Your reputation depends partly on how well your neighbors behave with their sending practices.
Why you should care
Shared IPs save you money and maintenance headaches. You don't need to warm up or maintain your own dedicated server address.
Most creators under 15K subscribers can use shared IPs without deliverability issues since reputable ESPs actively monitor sending behavior.
The challenge comes when one bad sender on your shared IP gets flagged for spam, potentially affecting everyone's deliverability. This creates a "roommate problem" where your emails might land in spam folders despite your perfect sending habits.
For growing newsletters, shared IPs work well until you consistently send over 50K emails per campaign. At that point, you might want to consider a dedicated IP for more control over your sending reputation.
Some resources we rely on
Ask Claude for help with Shared IP
Copy and paste this prompt into Claude or the AI of your choice. Be sure to tweak the context for your situation.
<goal>
Help me obtain and understand my ESP's shared IP ranges to improve deliverability and troubleshoot potential blocking issues.
</goal>
<context>
* I run a [FREQUENCY] newsletter with approximately [# of SUBS] subscribers
* Currently using [PLATFORM] as my ESP
* Experiencing [DELIVERABILITY ISSUE] with certain domains or corporate subscribers
* Need to understand my sending infrastructure to troubleshoot
* Want to provide IP information when subscribers can't find my emails
</context>
<output>
Please provide:
* A professional template message to request shared IP range information from my ESP's support team
* Step-by-step process to find my sending IPs on my own through email headers
* Guidance on how to use this information to troubleshoot deliverability issues
* Framework for maintaining records of IP changes for future reference
* Specific questions to ask my ESP about their IP reputation management
</output>
<example>
Support request template:
"Hello [ESP] Support Team,
I'm working on improving deliverability for my newsletter and need information about the shared IP ranges my emails are sent from. Several subscribers (particularly at [SPECIFIC DOMAINS]) have reported missing emails.
Could you please provide:
1. The current IP ranges used for sending from my account
2. Any recent changes to these ranges
3. Information about how IPs are allocated across your customer base
4. Best practices for helping corporate subscribers allowlist these ranges
Thank you for your assistance.
[YOUR NAME]"
</example>
<guardrails>
* Focus on practical application rather than technical theory
* Ensure requests are reasonable for standard ESP support teams
* Provide methods that work across major ESPs
* Avoid requesting proprietary information ESPs won't share
* Keep the focus on actionable deliverability improvements
</guardrails>