Warm-up is the practice of gradually increasing sending volume from a new domain or IP so mailbox providers can build a positive reputation profile before you reach full volume.
What good looks like#
- Done: Start with 20 to 50 messages per day per mailbox to your most engaged, opt-in contacts.
- Done: Double volume every 2 to 3 days while complaint and bounce rates stay clean.
- Done: Prioritize recipients likely to reply or click; positive engagement accelerates trust.
- Done: Monitor Postmaster Tools daily and pause the ramp if reputation drops.
- Done: Reach target volume over 4 to 6 weeks for a cold domain; faster if you have an established parent domain.
What bad looks like#
- Seen in audits: Warming with fake engagement networks that providers now detect and penalize.
- Seen in audits: Warming the IP but sending from an unauthenticated subdomain.
- Seen in audits: Treating warm-up as one-time; reputation decays after inactivity.
How to move from bad to good#
Work through the good list in order and re-verify after each change. Most teams find one or two items from the bad list already present; fixing those usually produces the largest improvement.
Frequently asked questions#
How long does email warm-up take?
Two to six weeks depending on target volume and whether the domain is brand new.
Do I need to warm up a shared IP?
The IP is already warm, but your domain is not. Domain warm-up still applies.