We’ve all gotten our fair share of those “batch-and-blast” e-mail messages from charities or politicians, sports teams or pharmaceutical companies. And a new study by US Email Trends and Benchmarks says we’ve all deleted our fair share.

These batch-and-blast messages are pushing some new content or project or promotion you don’t care about. They’re filling your inbox too frequently. And they’re failing to reach a huge percentage of their core audience because of it.

“Today’s consumer has limited tolerance for irrelevant messages, so targeted campaigns are clearly more successful than the batch-and-blast approach,” the study says.

The trends also show that when e-mail marketing is done well, the campaign will mean offline dollars for your company. A related Global Consumer Email study found that more than half of North American consumers made an offline purchase because of an email message. Numbers were slightly down in Europe at 39 percent, but almost two thirds of consumers polled in the Asia Pacific region made an offline purchase because of an email.

“While batch-and-blast messaging may seem appealing,” says Meghan Keane at econsultancy.com, “being sensitive to consumer preferences can pay off in spades, even if those messages go out to fewer people.”

E-mail marketing has the ability to harness a massive group of consumers, but you need to do it smartly.

According to US Email Trends and Benchmarks: “To effectively execute a permission-based email marketing program, it is important to incorporate consumer preferences such as frequency of communication, channel of communication and format as well as behavioral and other consumer data.”

Quick tip: Research finds that messages delivered between 10AM and 2PM convert more often.