New techniques make it possible to coordinate messaging across email and paid channels. But with email perceived by many marketers as a free channel, paying to reach the same people with ads may sound like a leap of faith. Let's explore how the benefits add up.

Your email subscribers all have one thing in common: They've asked for you to keep in touch. But if you look at where they spend their time online, the email inbox is just a slice of their online life--which they also devote to watching videos, using social networks, and using mobile apps and games. To connect with your subscribers, consider reaching outside the inbox.

In a study published with Facebook*, we showed how a retailer reached 77% more of their subscribers--who were 22% more likely to purchase when reached with an ad--just by targeting their existing email list with advertising. In a similar test, another retailer reached 162% more of their email subscribers using advertising--that's more than 2.6X as many subscribers exposed to the offer.

Sounds amazing, right? But how do you put an ROI on that? Here's how this approach could break down for a hypothetical company:

• Start with 1,000,000 email subscribers. These are the people you want to reach.
• Assume you can deliver email to 99% of them, and that 20% of those open the email.
• That's 198,000 subscribers who saw your offer.
• Assume 3% click and 4% of those convert. That's means about 0.12% of your subscribers responded and made a purchase.
• At $100 per conversion, that's $23,760 in revenue for the email send. Not bad, and testament to the extraordinary efficiency of email.

Now let's add in a paid component--target those exact same 1,000,000 email subscribers with advertising. Salesforce Marketing Cloud customers can do this easily using Advertising Studio.

• Take those 1,000,000 subscribers, and match them to an audience on Facebook. Let's Assume 66% of them can be matched this way, giving you an audience of 660,000.
• Then target those 660,000 with Facebook newsfeed advertising. Let's assume you can reach 60% of the audience. That's 396,000 email subscribers reached.
• Using data from the Salesforce Advertising Index for US Retail advertisers, let's assume a media cost of $5,560** for the ad impressions.
• Assume 1.5% of subscribers shown an ad click over to the store, and 4% of those convert for an average of $100.
• That's another $23,760 in revenue, measuring just those who click on the ad and convert. On a cost of $5,560, that's a 4:1 return.

That's doubling revenue from the same audience, just adding a second channel. And in this example, a media budget the size of a used motorcycle would get you there.

This is a basic strategy to increase reach and revenue--just coordinating your email send with paid media. With our Advertising Studio solution, it's a scalable and repeatable strategy. In my next posts, we'll double click into the numbers and talk about segmenting your audience to yield even greater performance, plus look at ways leading marketers are doing attribution for cross-channel programs like this.

Note: This was a hypothetical example of how advertising can enhance email marketing performance, not any specific campaign in particular.

1. Results based on a retailer's study conducted over two weeks in April 2014, targeting 925,000 US email subscribers using Salesforce Marketing Cloud and Facebook Custom Audiences. Facebook Offline Conversion Measurement matched and correlated ad impressions to email engagement and transactions. Findings are observational.
2. Media costs will vary by advertiser and campaign. In this case, we assume an average frequency of 2 ads shown per user, at a cost of $7.02 USD per 1,000 impressions (CPM). The $7.02 is a benchmark for US retail advertisers from the Salesforce Advertising Index of 2016, and will vary by placement, season, audience and other factors.

To learn more about the power of email and advertising, check out our full case study, Coordinating Channels: Email + Facebook Advertising Power the Customer Journey.