Infrastructure
What is Shared IP Address?
A sending IP used by multiple senders who collectively shape its reputation.
A shared IP is an outbound mail IP used by many senders, typically pooled and managed by an email service provider. The IP's reputation is the aggregate of every sender's behavior on it, so individual low-volume senders benefit from the pool's established standing. The provider handles warm-up and polices abusive senders to protect the pool.
Why it matters for cold email
Shared IPs let low-volume cold senders piggyback on an already-warmed reputation instead of building one from scratch. The trade-off is noisy neighbors: another sender's spam can drag down placement for everyone on the IP, so the quality and segmentation of the provider's pool becomes a key vendor-selection criterion.
Related terms
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