Custora has a new report out looking at ecommerce customer acquisition, finding that email continues to trend upward rapidly from year to year, and is well ahead of affiliate, banner ads, Facebook and Twitter. In fact, email had quadrupled over the past four years, according to the firm.

Do you have more success acquiring customers through email or through social channels like Facebook and Twitter? Let us know in the comments.

“The last few years have spawned massive changes in the world of online marketing,” the report says. “With U.S. e-commerce sales now topping $200 billion annually, digital marketers are getting savvier than ever. Customer acquisition trends reflect this evolution. Organic search still leads as the largest channel for online customer acquisition. But as more retailers move towards a ‘free-to-paid’ subscriber model and rely on third parties to help drive visitors to their sites, email and affiliate channels have seen an explosion in growth over the past few years.”

“Email marketing has been a growing trend in e-commerce, with an increasing number of retailers building communities and collecting email addresses, then converting those ‘members’ into customers,” it says. “Organic search continues to grow as a reliable channel, (accounting for nearly 16% of customers acquired) reinforcing efforts to complement products with relevant and informative editorial content along with investing in search engine marketing.”

Here’s where email stacks up compared to other channels for customer lifetime value, according to the report:

Custora analyzed data from 72 million people shopping on 86 retail websites, tracking where they were coming from, and how much they purchased over a two-year period.

You can download the full report here.

Interestingly, since this report came out showing the huge disconnect between email and Twitter for customer acquisition, Twitter announced that it has started experimenting with email-based ad targeting. Here’s how Twitter described it in a blog post:

How does this work? Let’s say a local florist wants to advertise a Valentine’s Day special on Twitter. They’d prefer to show their ad to flower enthusiasts who frequent their website or subscribe to their newsletter. To get the special offer to those people who are also on Twitter, the shop may share with us a scrambled, unreadable email address (a hash) or browser-related information (a browser cookie ID). We can then match that information to accounts in order to show them a Promoted Tweet with the Valentine’s Day deal. This is how most other companies handle this practice, and we don’t give advertisers any additional user information.

Josh Wolford has more on the offering here.

How is customer acquisition by email doing for you compared to other channels? Is email working better than social or vice versa? Let us know in the comments.

[via Wired]