I recently stumbled across an interesting website: Unroll.me. It’s a free service that helps people batch unsubscribe from email newsletters and subscriptions and in January, they gave out “awards” to the companies who lost the most email subscribers in 2013. 1-800 Flowers topped the list with a 52.5% unsubscribe rate. Yes, 1-800 Flowers lost over half of their list, thanks to Unroll.me! Here are some tips on getting your email marketing done right and keeping people from unsubscribing.

Why do people subscribe to begin with? Take a look and find out why people are subscribing to your service to begin with. Are they looking for deals or are they looking for information?

If discounts are your point of differentiation, you will live and die by the price sword and you can count on coupon-hunting customers punching the unsubscribe button the minute you stop offering discounts.

Are your emails location or event-based? Your emails about events in New York City are no longer relevant when your customers move to LA. Examining why people are subscribing to you to begin with may provide some insight into why they unsubscribe.

How can I miss you if you don’t go away? How often do you send emails out? Chances are, you may be sending too many, too frequently. Constant Contact asked 1,400 consumers why they opt-out of email subscriptions and 69% said they receive too many emails from the organization. Don’t fall for the fallacy of quantity as quality.

Let your customers miss you just a little bit and maybe they will look forward to your emails instead of wishing you would go away. Take a hard and honest look at your email frequency and ask yourself if you were receiving them instead of sending them if you would want that many.

Don’t subject your list to bad subject lines. How are your subject lines? I’m assuming you’re not falling into the trap of WRITING SUBJECT LINES LIKE THIS!!! since no one likes to be shouted at like that.

Are your subjects too long? I once had an English professor that said a good paragraph should be like a woman’s skirt: long enough to cover everything, but short enough to keep it interesting. Same thing applies to subject lines. Research from Constant Contact notes that subject lines with less than 50 characters have open rates 12.5% higher than those with 50+ character subjects. If possible, shoot for 25 to 40 characters (five to eight words).

Also, try to incorporate a sense of urgency into your subject lines. Don’t do the old hack trick of writing “act now!” or “limited time offer” in all your subjects. Instead, write something like this: “Only 5 days left to register for XYZ Conference!”

Work the body. So you’ve written a killer subject line and enticed your readers to actually open the email and then… oh no! Your email doesn’t render properly on your customers’ mobile devices. We’ve talked here about the importance of mobile and responsive design. Mobile is incredibly important! Don’t believe me? The data says that 48% of email is opened on a mobile device and 30% of subscribers will leave if the email doesn’t render properly.

As for the content of your email, is it targeted, or do you just blast everyone with the same thing? Segmentation (perhaps through personas) is a key part of successful email marketing and neglecting it will doom your results.

Who are you again? It’s possible your subscribers may not know who you are. If you don’t reach out to new subscribers quickly, they will likely forget all about you when you finally start sending them emails weeks or months later. Don’t let them forget you—reach out quickly when new subscribers join your list and try to stay in regular contact (just be careful about the frequency thing).

When they do leave, ask why. No matter how good an email marketer you are, it is inevitable that some people will unsubscribe at some point. When they do, try to find out why. A simple one-question exit survey with multiple choice answers like “too many emails,” “no longer need your service,” “information is not useful,” etc. can yield important insights as to why people opt out.

Use these tips and see if you can’t knock down your opt-out rates a few notches. If you’ve been making any of these email marketing mistakes, now you know how to correct your errors and soon, email will be a lead generating machine for you! And while you’re at it, sign up for the onDemand CMO email newsletter for more great tips!