Why aren’t more companies suppressing their emails?


By Guy Hanson, business development director, Database Group Interactive and member of the DMA Email Marketing Council.

A lot of focus is placed on suppression files created for the direct mail and tele-marketing industries.  But despite the fact that email marketing now forms a key component of most marketers’ strategies, the use of suppression is generally restricted to simply making sure emails that have previously bounced-back are excluded from future broadcasts.

However, there are even more reasons why suppression databases should be used to “scrub” email databases:

·       In email marketing, “sender reputation” is king: Two of the main criteria used to determine a sender’s reputation are “spam complaint notifications” and “rejects” (bouncebacks and block notifications). Email suppression must therefore ensure that these addresses are removed.

·       You don’t want to look like a “harvester”: Marketers should be excluding addresses that give the ISPs the impression that the list has been compiled by “harvesting”, ie, spammers who have written programs to gather email addresses published on web pages and so have high quantities of “sales@”, “info@”, etc.

·       Keep it marketplace relevant: Foreign addresses are also more likely to generate spam complaints, because of reduced relevance. So if your broadcast is for a UK-specific promotion, it’s best to remove them.

·       Avoid dormant addresses: Some of the major ISPs have established definitions of when an account is dormant. Hotmail, for example, determines that addresses that have been inactive for more than 180 days are dormant and should not be broadcast to. To enforce this, some dormant addresses are co-opted and monitored and if broadcasts are sent to them, sanctions could be applied against the sender.

·       Clean-up your mis-spellings:  In a large consumer list, it’s not uncommon to find over 100 different variations on how to spell Hotmail! Until recently that hasn’t been a major problem – emails generating a bounce-back on first use would be suppressed. However, several of the major ISPs are now co-opting these addresses as a new form of “spam trap”. So even lists with small quantities of mis-spellings are likely to generate ISP blocks.

A lack of awareness of the importance of email suppressions can significantly impact the delivery rates and therefore the overall success of campaigns. But to date, email marketing service providers have lagged behind their direct marketing counterparts in developing sophisticated routines to address these issues. 

Email marketers should start pushing their service providers to deliver this functionality to maintain a healthy sender reputation, ensure high inbox delivery and maximise campaign profitability.

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