As the market for email service providers (ESPs) has become much more competitive over the last few years, deliverability (the rate at which they get your emails into recipients’ inboxes) has become a key differentiator between the major players.
One of the factors that helps an ESP to achieve higher deliverability rates is to reduce the ratio of invalid emails they send on behalf of their clients. These invalid emails will result in hard bounces, and can harm the sender reputation of their servers. Why? Because many ISPs use the hard bounce ratio in their algorithms when deciding whether or not to allow emails into their network.
As a result, many ESPs now impose strict thresholds on the maximum number of bounces that their clients are permitted. It’s no longer enough to say that a list is fully opted-in, containing only direct subscribers. If the list contains more than a few percent – sometimes less – of invalid emails the ESP will usually suspend the client’s account, and ultimately withdraw the service.
At Email-Checker.com many of our clients come to us as a result of this very problem. They have had their email account suspended by their ESP, even though they have built their lists diligently and using best practice.
Email lists, even the best quality ones, can degrade at approximately 30% per year. So if you haven’t sent out a newsletter for even a few months, your bounce rate could quite easily exceed the ESPs acceptable threshold.
What about soft bounces? These are generally classed as email addresses that return error messages due to a full inbox quota, or where their mail server is down or experiencing issues. A few years ago, the distinction between hard and soft bounces was clear, i.e. soft bounces were OK as they were due to temporary issues. However, the treatment of hard and soft bounces is gradually converging as problems like full inbox quota generally mean an email account is “dead”, as quotas are now massive even for free ISPs. We treat soft and hard bounces in the same way, as our clients ultimately want to achieve as clean a list as possible when using our service.
