Dedicated vs Shared IP for Email: Which One Do You Actually Need?

How Sending IPs Work

Every email you send originates from an IP address. Mailbox providers track the sending history of each IP to build a reputation score. Good senders get good IP reputation; spammers get blocked.

Your ESP (SendGrid, Mailgun, Amazon SES, etc.) either assigns you a shared IP (used by multiple customers) or a dedicated IP (used only by you).

Shared IP: The Default

With a shared IP, your emails go out from the same IP address as other customers of your ESP. Your reputation is pooled — you benefit from good senders and suffer from bad ones.

When shared IPs work well:

• You send fewer than 50K emails per month
• You use a reputable ESP that monitors its shared pools aggressively
• You're just starting out and don't have enough volume for a dedicated IP

When shared IPs cause problems:

• Another sender on your pool triggers a blacklisting — your emails get blocked too
• Your ESP doesn't police its shared pools and allows low-quality senders

Dedicated IP: Full Control

A dedicated IP means no one else sends from your IP address. Your reputation is entirely in your hands — for better or worse.

The Volume Threshold

This is the critical factor most people get wrong. A dedicated IP needs consistent sending volume to maintain its reputation. If you send 10K emails on Monday and nothing for the rest of the week, your IP looks erratic to mailbox providers — and erratic IPs get treated with suspicion.

The math: To keep a dedicated IP healthy, you need to send consistently — ideally every day. At 100K emails per month, that's roughly 3,300 emails per day. That's enough for mailbox providers to build and maintain a reputation profile.

Below this threshold, the IP doesn't generate enough data points for providers to trust it. You're better off on a well-managed shared IP.

When to Switch to Dedicated

Consider a dedicated IP when:

1. Volume exceeds 100K/month consistently — Not one big campaign, but steady daily volume
2. You're being affected by bad neighbors — If your shared IP has reputation issues you can't fix
3. You need maximum deliverability control — Regulated industries or high-value transactional email
4. You're sending from multiple ESPs — A dedicated IP per ESP gives you clearer reputation data

Domain Reputation vs IP Reputation

In 2026, domain reputation has become more important than IP reputation — especially at Gmail. Google has publicly shifted to domain-based reputation signals, meaning your domain's sending history matters more than which IP you send from.

This doesn't make IP reputation irrelevant, but it means that switching IPs is no longer a way to "reset" a bad reputation. Your domain follows you everywhere.

Frequently Asked Questions