Shared IP
01 Definition
Shared IP meaning: A sending IP address used by many senders, who collectively influence its reputation.
A shared IP is an IP address that multiple senders use together, usually managed by an ESP. Reputation is pooled, so an established shared IP can benefit low-volume senders, but another sender's bad behavior can also affect your deliverability. It suits smaller or irregular senders who cannot sustain a dedicated IP.
Why it matters
How Shared IP fits the work
Shared IPs let low-volume senders inherit an established reputation and skip warming, making them practical when you cannot send enough to keep a dedicated IP healthy.
In context
A small nonprofit sending 3,000 emails a month used a shared IP rather than warming and maintaining its own dedicated address.
Practical note
You cannot fully control a shared IP's reputation because neighbors' complaints and spam traps affect you, so choose an ESP that actively polices its shared pools.