A good article from Matt Blumberg on how to prevent your email newsletters from getting blacklisted with various ISPs.

There are several immediate steps you should take to reduce complaints, build customer trust, and increase delivery:

– Use confirmed or double opt-in when building your list, to make sure the people you are sending email to really want to be getting your communications. Sending a welcome message also further verifies your permission to email.

– Make sure you only send email that matches what you say you?ll send upon registration. For example, if they sign up for coupons, don?t also send a newsletter unless you have explicitly told them you will.

– Be sure any language surrounding how you use email addresses and what email you?ll send is clearly stated up front. Do not bury it in a privacy policy.

– If you don?t share your customer information with others, promote your privacy policy at the time of registration, and reiterate your sensitivity to customer privacy in other relevant communications.

– Make unsubscribe links obvious, and make sure they work. Also, if your company?s list is used by different departments, make sure emails are removed from all lists.

– Monitor public blacklists to make sure your IP addresses are not listed. If you become listed on a blacklist used by ISPs, your messages could go missing.

More here