IP warmup

Internet Protocol (IP) warmup is the process of gradually ramping up the volume of emails sent from a dedicated IP address to build a domain’s reputation among inbox service providers (ISPs). Typically, when a brand suddenly starts sending multiple emails, ISPs suspect its IP address to be “spammy” and question if the brand is truly sending high-quality content to recipients, which is why brands must warm up their IPs.

At Mailgun, we recommend steadily building the sending volume of your IP address or relying on an IP warmup service from an email service provider like us to ensure your IP reputation doesn’t take a hit as you start sending an increased volume of emails. If you have a bad IP reputation, ISPs won’t accept your carefully created messages or will refuse to place them in your reader’s inbox.