How long should a new sending domain warm up?
Last updated
We warm up new sending domains for about 14–21 days before sending at full pace. During warm-up, mailboxes send small, gradually increasing volumes so mailbox providers can build a reputation for the domain. Authentication (SPF, DKIM, DMARC) should be in place before warm-up starts. Rushing it can damage deliverability, which is slow to repair.
What we do during warm-up
- Set up SPF, DKIM and DMARC.
- Ramp volume gradually.
- Review your first batches with you, so nothing is wasted.
This range is what we use; vendors and providers publish their own guidance.
Sources
Questions people ask
How long should a new sending domain warm up?
We warm new sending domains for about 14–21 days before sending at full pace. Other vendors publish their own ranges.
What happens during those days?
SPF, DKIM, and DMARC go on first. Volume ramps gradually, and we review your first batches with you.
What if I skip the warm-up?
Rushing it can damage deliverability, and that damage is slow to repair.