EmailA study by Return Path has found that 21% of marketing emails sent are failing to reach customer inboxes.

They found that global email deliverability rates had declined dramatically in the last year, falling from 83% in 2014 to 79% this year. These results show that one out of every five emails sent are not reaching their intended recipient; they’re either going straight into the spam folder or being blocked by mailbox providers.

During the study, Return Path analysed over 350 million marketing emails sent from a range of recognised companies. The findings are based on more than 150 mailbox providers from Europe, North America, South America and the Asia Pacific regions.

The study found that the US has particularly low deliverability rates, with only 76% of emails reaching customer inboxes. This represents over a 10% drop from 2014, when deliverability rates in the US were 87%.

This dramatic drop in deliverability rates has been attributed to improvements in spam filters. Mailbox providers are using increasingly sophisticated algorithms to help understand what their customers want (and don’t want) in their inboxes. While this creates a much better experience for consumers, for email marketing, it highlights the importance of making every effort to stay out of the spam folder.

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