One of the simplest ways to avoid getting blacklisted is by using throttling techniques, which keep you from over-saturating your prospects’ e-mail servers.
Throttling is exactly what it sounds like: managing the flow of e-mail going out of your servers and into another company’s. This is important because one of the ways a company can get placed on a blacklist is by sending too many e-mails from a particular IP address to particular servers.
Most corporate servers as well as ISPs set limits as to how many e-mails they will accept from an individual IP address within a set period of time, he said. “Once it crosses that threshold, the mail server starts blocking your IP address,” Ashery said.
Corporations and smaller ISPs may set that threshold between 1,000 and 10,000 messages within a 10-hour period, while larger ISPs might have much higher limits, such as 50,000 per day per IP, he said.
E-mail marketers can get around this limit by segmenting their lists manually or having their ESPs send out staggered groups of messages. “It’s a very big undertaking, but if you have a large list, you really need to do this one way or the other,” he said.