SES warm-up, without a dedicated IPMost warm-up advice assumes an IP you probably do not have.

IP warm-up as a concept comes from a world of dedicated sending IPs, where a brand-new IP address has no history with mailbox providers and needs a slow ramp to earn trust before it can send high volume without getting throttled or blocked. That world still exists, but standard Amazon SES does not put you in it: your mail goes out through Amazon-managed shared IP pools that already carry substantial sending history across many customers.

What actually has no history when you start is your sending domain, not an IP. Mailbox providers weigh domain reputation heavily alongside authentication and engagement, and a domain that has never sent real volume looks exactly as unproven to Gmail or Outlook as a brand-new IP would in the dedicated-IP world. The ramp discipline is the same idea, applied to the right target.

The first sends from a new domain set the tone. Mail to people who recently opened or clicked something from you, if you are migrating from another provider, or to an early access group that opted in specifically, produces the positive engagement signals mailbox providers weight most heavily in the first days. Mailing your full list on day one, cold, is the fastest way to generate the bounces and low engagement that make the next weeks harder.

1. Pick a starting volume you are confident is clean: your most recently engaged, smallest reliable segment.
2. Increase volume stepwise, roughly doubling each step, as long as bounce and complaint metrics stay clean at the current level.
3. Plan in weeks, not days. How long a ramp takes depends on target volume, list quality, and how mailbox providers respond, none of which you can force faster by sending more.
4. Hold at the current volume, or step back, the moment bounce or complaint rates tick up. Resuming the ramp before the metric recovers usually makes the next step worse, not better.

There is no published fixed timeline for how long this takes, because it genuinely depends on your list and your volume target. Clean metrics at each step are what let you move to the next one faster; a spike is what tells you to wait.

Check bounce and complaint trends before every step up, not after. AWS documents review territory around 5% bounces and 0.1% complaints, with enforcement risk around 10% bounces and 0.5% complaints (Using reputation metrics to track bounce and complaint rates, SES Developer Guide, fetched 1 September 2026); a domain still warming should be staying well under those, not testing how close it can get. If you send from more than one domain, watch each one separately. A problem on one domain does not mean the others are also in trouble, but it does mean that domain specifically should hold or step back while the others may not need to.

Dedicated IPs are a separate AWS add-on, chosen deliberately by senders who need isolation from other customers' sending behavior, usually at high enough volume that shared-pool reputation swings from other senders become a real business risk. That decision comes with its own warm-up rules, since a dedicated IP genuinely does start with no history of its own. For most senders below that volume, the shared pool plus a disciplined domain ramp is the whole story, and adding a dedicated IP before you need one just adds a second thing to warm at once.

Each sending domain in SendBunny runs in its own SES tenant inside your account, so one domain's rough patch during a ramp does not drag down the others while you warm it. Bounce and complaint charts per domain, alongside a health strip visible on every screen, show whether the ramp is working before AWS's thresholds do. It is $199 once, installed into the AWS account you already own, and it does not ramp volume for you; the schedule and the judgment stay yours.