Shocked At The Idea Of Better Email Deliverability?

Email Deliverability, Explained:

EMAILI was looking at several Online Magazine rate cards to analysis the open rates of email campaigns. I compared that number to the cost of advertising on a typical email list. I was surprised to see published numbers such as a 23% open rate for a 48,000-member list: that’s only 11 out of every 50 people expected to either click on the email or open it and read it. I thought that the percentage was rather low. Being a company in the email list hosting business for the past 19 years, I have seen worse (rented lists) and much higher open rates for customers on Dundee’s hosting email platform.

Those open rate numbers tell me, that for some marketers, all the adjusting, tweaking, and testing, might only be done for less than 25% of their subscriber base.  That’s something to think about!  If you find yourself in that low range, you can improve the chances of an email being open and read, by looking at your deliverability first.

When you send to your list, emails may be blocked by your subscriber’s email provider. Even if delivered, the messages may not pass the recipients filter settings in their email client. Both indicate that you do not have total control over your deliverability, so what can you do?

Consider the following to find out:


Authenticate – where are you from?
  • Deliverability depends on Email Authentication, the process by which an ISP can verify the supposed identity of the sender. While there is no recommended standard for email authentication, there are several ways available to do so. Some available Authentication Systems include SPF and Domain Keys. Messages that cannot be authenticated by the receiving ISP may be blocked.
  • Email has many handlers, which translates into “not all your email will be delivered as intended.” ISP’s want to handle incoming email problems before they get out of hand and quickly resolve those “Report Spam” button issues. One way they do this is by using a communication system known as FBL or “complaint” Feedback Loops. Check with your ESP and see if this is something they are using.


Legal and compliance
  • Deliverability depends on your email practices. As a legitimate email marketer, you want to disassociate yourself with any inkling of being a SPAMMER. Follow the CANN-SPAM ACT and check local State Laws. Listen to your ESP, they should know the Best Email Practices. Your ESP can also help you with your online email reputation and assist you when someone complains.
Your messages should:
  • Never use misleading header information
  • Keep Subject Lines on point, don’t be deceptive
  • Make it clear to the recipient this is an AD if you’re sending an AD
  • Include your location
  • Contain an easy tested opted-out option

In addition, make sure your affiliates are doing what they are supposed to be doing and not giving you a bad name by spamming your product to others. And as you probably know, refrain from buying lists. (addresses scrapped from unsuspecting websites are bad news).

Permission Please

Deliverability is about permission. What policies do you have in place when it comes to adding members to your email list? How do you interpret permission-based email marketing?

A permission-based email comes in two forms:
  • Expressed permission, the best type of consent to get, as it comes directly from the user himself (herself). For example, checking a box on a website registration form to request your email newsletter.
  • Implied permission, permission that is not given, it’s inferred from an action or relationship, such as not removing a pre-check on a website form for list membership.

If you place folks on your list without permission, you are more likely to be reported as a spammer: a status email marketer can do without.


Most ESPs (I know we do) will give you a dedicated IP address for your mailings. Your sender reputation will be tied to that address.

Deliverability depends on your sender reputation. If you mail non-permission unwanted emails (SPAM) your chances of being Blacklisted are high. Blacklisted IP addresses will cause ROI losses because once you are on a Blacklist, your emails will be earmarked as such and the ISP may refuse the receipt of your message.

Being associated with a Blacklist is something you should be concerned with even if your list is all opted-in, especially if you do not have a dedicated IP address. In those cases, your ESP’ reputation is yours, as well as the reputation of those 3rd party links you might use.  You can check your reputation status and the status of your ESP with the major SPAM databases by reviewing the websites of the reporting agencies such as,, and SpamCop.   There are also free tools you can use to analyze those URLs included in the content of your messages as you don’t want to include an IP address that is on a Blacklist; being on or associated with a Blacklist may stop your email dead in its tracks.

Spam Complaints

Deliverability can suffer if you get too many spam complaints; reports made by email recipients against emails they consider to be unsolicited.

Complaints can happen because:
  • Some folks may not remember signing up for your newsletter, instead of unsubscribing they report you as a spammer.
  • You continue to re-add those unsubscribes, (Your unsubscribe rate, ideally should be under 1%.) you should delete them and move on. List Chun is a natural part of the sales cycle and there’s little you can do about it.

I’m sure you heard it said, avoid spammy words in your email subject lines. The list includes but not limited to “Save”, “Huge”, “Discounts”, “Free” and “Cash” – you get the idea. However, ESPs, ISPs and Spam filters have grown up, spammy words are no longer spammy words, more importantly, are a combination of online factors such as your sender reputation – the bottom line your Spammy words may not be an issue: so advertise your Huge Savings with a Free catalog without being blocked for the word Free.

Spam and Spam filters go hand in hand. Why should you be concerned about Spam Filters? Because they are being used everywhere and can affect your success as an email marketer. Spam filters are configured to work on a list of criteria, which depends on the information provided to the software and user. They can filter on just about everything, from content and formatting to sloppy coding. The Science behind the filter is interesting, I’ll cover Spam Filter Specifics in a future blog.e

User Engagement

Subscriber engagement is an identifiable and important metric for email deliverability. By definition, when an email is engaged there is a positive action taken on it by the recipient. It is believed that some ISP’s utilize the user engagement stats to determine if your sent email messages are actually wanted by your subscribers, compared to those messages that aren’t wanted or acted upon (engaged). With this information in hand, the ISP may take adverse action on your mailings, which may include slowing down your email delivery to blocking your email altogether. Logically, then, the less engaged your email recipients are the more undesirable effect on your reputation.

Design and Content

Positive deliverability may depend on content and personalized crafted targeted emails, which will give you a higher chance of reaching the inbox and increase levels of engagement once there. What you say, how you say, how the email renders on a mobile device versus a laptop affect the email experience; likewise using a “correctly coded” identifiable template versus a poorly coded template can cause deliverability issues. A badly coded design, for example, may trigger spam filters.

In addition to mobile rendered email, it’s important to provide a plain-text alternative for those organization that does not accept HTML emails. If they can’t read HTML, guess where that email will go.


How Much You Mail and When

Email deliverability depends on how often you mail; do you frequently send random email campaigns, if so, that practice will lower your sender score. Instead of random mailings, be consistent and mail on a schedule. When you send bursts of increased emails, you could be sending a message to ISPs that your list suddenly (mysteriously?) grew, which may trigger unwelcome filtering
ISPs typically look for emailing regularity that reflects a steady list growth. For a list owner that has 1,000,0000 subscribers and emails to 500,000 the first of every month, it wouldn’t be wise to decide to mail to all 1,000,000 on the second of the month, without any warning. The better way is to slowly build up to 1,000,000 emails on the new mail day: maybe 250,000 for a while, then 500,000 and so forth.


When you look at your deliverability rate common sense will tell you to remove bounced emails. In reality, most senders will retain bounced back addresses to resend to them in the future, believing these bounces were the result of full mailboxes or misspellings. A detailed Bounce Report, from your ESP, will allow you to distinguish which bounces came from where: a full mailbox which indicates  a soft bounce,  or a  hard bounce when the email addresses don’t exist


And once again, optimum deliverability rates and a better sender reputation is a primary concern for marketers because deliverability issues equal significant revenue loss. One way to make your deliverability rates high is to maintain a “clean” email list. A “clean” email list (free from role accounts, misspellings and so forth) will yield better deliverability results when personalized and relevant messages are sent to the subscriber; which should reduce the chance of Blacklisting, ISP blocking, or extreme bounce rates.

Keep that undeliverable number down with consistent list hygiene such as:
  • Integrity checking. Are email addresses in the right @ format, do they end with a .com, .net, .org or other domain. Do you have role address, such as president, info or sales instead of a destination person like
  • Upfront vetting and common sense. Was there typos when the email address was entered, so that email address for that recipient just doesn’t exist, perhaps the user did enter the right email address then switched accounts or left the company. Maybe their email box was full and not accepting email.
  • Automatic bounce handling, which should be part of your ESP offering. Without it you must, on a regular basis, remove bad addresses from your list. (Dundee’s email platform handles all error mail, including bounces (transient and permanent failures)

There are so many factors that affect deliverability rates, I could write a book! Just remember the best defense against delivery problems, like always, starts with you. Maintain an excellent email reputation and stay focused on all the other factors (like sender score) that influence your mailing reputation.