To see how well major online retailers have been doing at managing their sender reputations -- which is one of the keys to deliverability -- the Email Experience Council examined the sender addresses used by 95 retailers during the past 18 months. What we found is that a third of them used more than one email address to send their core email marketing campaign during the past 18 months.
While some retailers sent different flavors of their email campaign under different addresses, the majority of the time the retailer changed the primary sender address (presumably because of reputation problems). Indeed, some sender addresses bore the fingerprints of an ESP change.
However, there were a number of retailers that send their core email marketing campaigns under at least two addresses. For example, Lillian Vernon sends their Lillian Vernon and Lilly's Kids emails under different addresses. Spiegel and Spiegel Home, and Crate & Barrel and CB2 emails are also sent via different senders. Managing additional sender domains for each sub-brand is strategy that's in the minority -- in part because it makes it more difficult for subscribers to whitelist you, since they have to add two or three or more addresses to their address book instead of just one.
While the majority opt for sending all their regular emails from a single domain, the camp is nearly evenly split when it comes to sending welcome emails. Our research indicates that 48% of major online retailers send their welcome emails from a different email address than they send their regular emails from. Presumably this is to shelter the reputation of the welcome email sender domain. Having that welcome email delivered to the new subscriber's inbox is crucial, as 62% of retail welcome emails ask the subscriber to add them to their address book. Getting subscribers to whitelist you at the very beginning of the relationship is the Holy Grail of deliverability.
Interestingly, 11% of major online retailers sent their welcome emails from a different email address this year. Even more interesting is the fact that 75% of those retailers moved toward using a single sender address for all their core email marketing campaigns, including both welcome and regular emails. That would also seem to support the idea that, in general, using a single sender address is a more powerful strategy than sending emails from multiple addresses, depending on their content or purpose.