Whitelists, blacklists and Spam complaints are major methods of controlling unwanted e-mail. There are different levels of control – at the ISP, the ESP (or you!) and user-level. Understanding these elements of e-mail marketing is not only essential, but in some instances, required under law.

For a brief overview of the topics discussed in this article, please see Part One of this topic in our E-Mail Marketing Series:
V. E-mail Marketing – Whitelist, Blacklist, Spam Complaints, Oh My! (Part One)

Whitelists
Whitelisting is similar to a blacklist, in that it’s a list of IPs and ISPs, with one major difference. Whitelists are lists of senders whose e-mail will always be delivered, regardless of content or spam filter settings. This is usually an active act of consent on the part of the e-mail recipient. Have you ever seen an e-mail asking you to add a certain e-mail address (usually the one that the e-mail is from) to your allowed senders or address book? This will whitelist the e-mail address and allows mail from that sender to be received by your ISP without interruption.

ISP Whitelisting is a completely different process altogether – instead of asking one of your recipients to let you in, you are asking an ISP to allow your mail for all of its users. Understandably, getting on an ISP whitelist can be both costly and difficult to attain and maintain. Just like a user can move you from the allowed senders to junk – an ISP can revoke whitelist status at any time for violations such as sending unsolicited e-mail or having an Open Relay.

Blacklists
Blacklists are lists of IPs and sometimes ISPs of known spammers. To seriously work in e-mail marketing, you must be aware whether or not the IPs and domains you are using are listed on any blacklists. To start, check MXToolbox.com and SenderBase.org. SenderBase will even help identify if you are on several blacklists and also what IPs or domains you might be associated with. MXToolbox has a wealth of e-mail delivery tools, including verification of Reverse DNS, Open Relays and more.
Another hint that you are blacklisted may be a large increase in the number of bounces. ISPs will reject (bounce) the mail if you are blacklisted, among other reasons. Make sure you have the ability to monitor this in your ESP of choice.

If you are on a blacklist, start taking action immediately to rectify the situation. Your reputation is on the line once you are listed on an SBL and some lists will even post identifying information, such as the name, company name, address and phone number of the person who registered the offending domain.

Keep in mind that IPs and domains are not added to blacklists on a whim. There will be a significant number of complaints at the ISP level, combined with questionable opt-in practices and non-targeted/general e-mail content that lands one on a blacklist.
Unless you are well-versed in e-mail marketing, it’s a good idea to hire a professional to help with whitelisting, blacklists and spam complaints.

Next up in our E-mail Marketing Series – Part VI: From & Subject Lines Explored