Deliverability
Domain warm-up
Gradually increasing how much email you send from a new or newly used domain, so mailbox providers can build a reputation for it before you send at full volume.
Why domains need warming too
Mailbox providers now weigh domain reputation more heavily than IP reputation. A domain that has never sent email, or hasn’t sent in months, has no track record, so even on a platform’s well-established IPs, a sudden flood of mail from it looks risky and gets throttled or filtered.
A practical warm-up schedule
Numbers vary with your list, but a common pattern looks like this:
- Days 1–3: a few hundred emails a day, only to your most engaged recipients.
- Week 1: roughly double each day or two while bounces and complaints stay low.
- Weeks 2–4: keep increasing until you reach your normal volume.
- Throughout: send on a steady schedule, and pause increases if you see deferrals or a rise in complaints.
Warm up with your best mail
Transactional email like receipts and password resets is ideal early traffic, because people expect it and open it. Hold off on big campaigns to older or less engaged contacts until the domain has a solid history.
Protect your main domain
Many teams send marketing from a subdomain such as news.yourdomain.com and transactional mail from another, such as mail.yourdomain.com. Each builds its own reputation, so a campaign problem doesn’t slow down password resets. In MailCraft, each sending domain or subdomain is verified and tracked separately.
Let MailCraft handle the details
Authentication, bounces, complaints and suppression are built in. Start free with 3,000 emails a month, no credit card required.
Start freeRelated terms
Full glossaryDeliverability
IP warm-up
The practice of gradually increasing send volume from a new domain or IP so mailbox providers build trust in your sending pattern before you reach full volume.
Deliverability
Sender reputation
A score mailbox providers maintain for a sending domain or IP based on engagement, complaints and bounces, which determines whether your mail reaches the inbox, spam, or gets rejected outright.
Sending & delivery events
Throttling (rate limiting)
When a mailbox provider temporarily limits how much mail it accepts from you, usually answering with a temporary error, because your volume jumped suddenly or your reputation is uncertain.