Shared vs dedicated IP for cold email — which should you use?
Most cold email senders should use the shared, reputable IPs of Google/Microsoft mailboxes — a dedicated IP only pays off at very high, consistent volume. Here's the trade-off.
Short answer: for most cold-email senders, the shared IPs behind Google Workspace / Microsoft 365 mailboxes are the right choice — they carry established reputation and need no warmup of the IP itself. A dedicated IP only makes sense at very high, consistent volume (tens of thousands/day) where you can keep it warm; below that, a dedicated IP starts cold and hurts you. Domain + mailbox reputation matters far more than IP choice for typical cold outreach.
Shared IP (Workspace / M365 mailboxes)
- Pros: established reputation, no IP warmup, simple, ideal for cold at normal volume.
- Cons: you share reputation with other senders on that pool (rarely an issue with Google/MS).
Dedicated IP
- Pros: full control of IP reputation at scale.
- Cons: starts cold, needs constant high volume to stay warm, more ops overhead.
The rule
Under ~50k/day, use reputable shared infrastructure (connect Google/Microsoft/SMTP mailboxes) and focus on domain reputation + warmup. Autocloz works with any mailbox provider and manages warmup, caps and rotation regardless of IP model.
> Start free — connect reputable mailboxes; skip the dedicated-IP headache.