The Retail Email Index, which monitors the promotional email volume of the top 100 online retailers, reports that retailers on average sent a whopping 14.3 emails to each subscriber per month during November and December 2009, with 3.9 messages in the week ending December 18th (typical shipping cutoff date).
While increasing frequency may result in higher sales, there are dangers of sending so many messages. Smith-Harmon’s latest research report, the 2010 Retail Email Guide to the Holiday Season, asks you to consider the drawbacks:
1. The cost of replacing subscribers lost to higher churn
2. The sales lost because increased spam complaints caused delivery problems
3. The opportunity cost of lost sales due to higher ignore rates as subscribers tune you out because you are over-sending
On top of the spam issue, ISPs are factoring engagement (opens) as part of their reputation score calculation. Sending a lot of messages that subscribers ignore signals to ISPs your messages are not relevant, which can hurt your future delivery to subscribers across that ISP.
Does that mean you shouldn’t ramp up frequency at all? Heather Blank, vice president of strategic services at Responsys, recommends that marketers be strategic about increasing volume, identifying customer segments that are more tolerant of high volume.
You can segment out these customers by looking at previous engagement metrics like open rates, click throughs and purchase rates. You can also ask customers to update a “preference center” where they can choose frequency, types of offers and so on (but don't rely on this tactic, as only a few will actively manage preferences).
For more holiday email tips, Smith-Harmon is offering their latest report free of charge.