What dedicated IP addresses are#
A dedicated IP is used only by your mail; a shared IP pool is used by many senders on the same platform. Dedicated IPs give control over reputation but require volume and warm-up; shared pools borrow the platform's reputation.
Why it matters#
Choosing wrong either exposes you to neighbors' behavior or leaves an IP too cold to build reputation.
How mailbox providers use it#
Gmail, Microsoft, and Yahoo combine authentication results, sender reputation, and recipient engagement into a placement decision made per message. Dedicated IP addresses feeds directly into that model, and weaknesses compound with other signals.
How to measure the impact#
- Baseline inbox placement with seed tests before any change.
- Make one change at a time and hold volume steady.
- Re-test after 48 to 72 hours; provider models need time to update.
- Track Postmaster Tools and SNDS alongside your seed results.
Improving it#
- Estimate steady daily volume; below roughly 50,000 per day, shared pools usually perform better.
- If dedicated, warm up over 4 to 6 weeks and keep volume consistent.
- Separate transactional and marketing onto different IPs or pools.
- Monitor SNDS and Postmaster Tools per IP.
Frequently asked questions#
Do I need a dedicated IP for good deliverability?
No. Domain reputation dominates. Dedicated IPs are for high-volume senders who want isolation.