Email warmup is the process of gradually increasing sending volume to establish trust with inbox providers. Learn how warmup works and common mistakes.
Email warmup is the practice of gradually increasing your sending volume from a new domain, mailbox, or IP address to build a positive sender reputation. Inbox providers are cautious about sudden high-volume sending from new identities because it often correlates with spam.
Warmup typically starts with low volumes sent to highly engaged recipients, then increases steadily while monitoring bounces, complaints, and engagement. Consistency matters more than speed, and warmup should include proper authentication and stable sending patterns.
Common mistakes include ramping too quickly, sending to cold or purchased lists, and ignoring complaint signals. A thoughtful warmup reduces the risk of spam placement and helps establish long-term deliverability.