Learn From The Experts Articles
Email Campaign Success
By Tommi Pryor
The subject line of your email plays a crucial role as to whether your email is opened or even if it makes it into the “inbox” in the first place. Because if its importance, this article will focus entirely on this all-important topic, the email subject line. More consideration needs to be given to the subject line, than the rest of the email.
Subject Lines Impact Delivery
ISPs and web-based email hosts such as AOL, MSN, GMAIL, and Yahoo are known to utilize spam filtering technology that score incoming emails for spam characteristics. The higher the score, the more likely the incoming email is spam. Each ISP and email host sets the score threshold for blocking the email or diverting it to the junk folder based on a preferred tolerance level. If your email message scores above the tolerance level, it will never make it into the recipients’ inbox on their ISP’s email server.
One of the elements heavily weighted in the scoring process is the email subject line. Some of the variables that factor into the subject line score are subject line content, use of punctuation, and use of uppercase characters. These factors are key to subject line evaluation because they may typify how spammers utilize subject lines.
For instance, spammers like to use words that they believe will bait consumers to open their email messages such as “Free”, “Discount”, “Sale”, “Guarantee”, “Act Now!,” and “% off”. However, if you do a quick check of your own junk folder, you’ll see that your spam filter has captured numerous emails using keywords similar to these expressions. Political marketers may feel their email messages are not at risk because they aren’t selling anything. However, this is certainly not the case.
Other keywords known to red flag an email message as spam include such seemingly innocuous ones as “Reminder”, “Act Now”, “Help” or even “Your family.” This means that a political marketer’s email subject line like “Reminder to cast your vote on Friday” or “Reminder to mark your calendar for our event” can red flag your email. So can “Don’t let the opposition outspend us. Act now!”, “Senator Doe needs your help!” or “Support the candidate who will lower taxes for your family.”
So how can you make certain that you aren’t unintentionally inserting keywords into your subject lines that will trigger the spam filters? One good gauge is the list of trigger words listed on SpamAssassin’s web site at: http://spamassassin.apache.org/tests_3_2_x.html. (SpamAssassin is an open source spam filter program in wide use on commercial email servers).
If you peruse this list, you’ll also note other subject line red flags are created from mis-spelling of words such as “Fharmacy” instead of “Pharmacy” or spaced spellings such as “F R E E” instead of “FREE.” In addition, you’ll note that the substitution of symbols for letters in a word acts as a score trigger (“L@@k” instead of “Look” or “L00K” instead of “LOOK”). And, you’ll note that the use of uppercase words and punctuation in subject lines, especially question marks or exclamation points, also add to a negative spam score.
Subject line length also comes into play with respect to deliverability. The conventional wisdom is that you should keep your subject line to no more than 50 characters or risk triggering the spam filters.
Impacting Open, Click-Through, Conversion Rates
Until recently, there was really only one school of thought regarding subject line length. For a variety of reasons, industry experts agreed that a shorter subject line was a better subject line.
In addition to impacting deliverability, email subject lines over 50 characters are often subject to word-wrapping (places the subject line on two or more lines) or truncation (the line ending is cut off by the recipients’ email client). This can have disastrous results. For instance, take a subject line that is supposed to read “Senator Doe comes out in favor of XYZ policy”. Now let’s say Senator Doe is a conservative candidate running on a family values platform. Look what happens when the subject line gets truncated at 21 characters: “Senator Doe comes out”. The intent of the subject line is completely altered and, in this case, likely to the detriment of the candidate. (In reality, it is unlikely that any email client would truncate a subject line at just 21 characters but this example serves to illustrate the possible impact of subject line truncation).
IE browser users can test their subject line appearance with a free online tool available online at: http://www.emaillabs.com/tools/from_subject_line_tool_popup.html. Many will utilize multiple email accounts with the major ISPs and free web mail accounts in order to test how their subject lines affect the delivery of their message throughout the major ISP’s. Taking the time to “test” your message, can clearly determine if your email will be delivered to that ISP’s inbox.
Interestingly, some recent industry studies have turned the conventional wisdom on subject line length on its ear. One study reports that shorter subject lines increase the open rate while longer subject lines increase the click-through rate (while decreasing the open rate). Another reports that short subject lines under 50 characters increase the open rate as do long subject lines over 70 characters, but that those falling in between at 51-69 characters decrease the open rate. It is clear that it is difficult to figure.
So now what do you do? The answer is qimple. To increase your rate of success, you must test, test, test. What works may be counter-intuitive. And, what works with one list may not be what works with another, so you should keep testing. Here’s how to conduct a simple A/B Split-Test to determine the impact of subject line on the open rate:
Create your email content remembering to minimize the ratio of graphics to text as we advised in our previous articles. Incorporate several links back to a dedicated landing page containing a quick and easy sign-up form requiring minimal fields that need to be completed (you can gather more information from the subscriber during the welcome process). Now create a minimum of two subject lines. Make them similar so that you are testing only one thing: subject line length. Subject Line “A” should be fewer than 50 characters (we actually usually recommend fewer than 39 characters), while Subject Line “B” should be greater than 70 characters. Now take 10% of your list and send your email with the “A” subject line, while taking another 10% of your list and sending your email with the “B” subject line. After 6-8 hours, look at your open rate and identify the method with the higher success rate. Deploy the email to the remaining 80% of your list using the more successful subject line.
If you are testing the click-to-open (CTO) rate, you will want to track whether subject line “A” or “B” produced the higher number of click-throughs to your web site as a percentage of those who opened the email. Or, if testing the click-to-delivered-rate (CTD) rate, you will track your winning subject line against the number of emails transmitted with each subject line less bounces. Similarly, If you want to track which subject line produced the higher response to your call-to-action (sign-ups, donations, etc.), then you will want to evaluate which subject line produced the higher number of call-to-action responders as a percentage of click-throughs (Conversion Rate).
One thing that the industry seems to agree on is that straightforward, no-nonsense subject lines outperform sensational subject lines and teaser subject lines. This being said, you should still test this premise. In the heat of a political battle, it could well be the more sensational subject line that peaks interest despite the conventional wisdom. You’ll only know for certain if you test the straightforward subject line against the sensational subject line (but in this test, you should keep their lengths similar so you are again testing against one aspect).
While we always encourage testing of major variables such as email content, images, message length, etc., we understand that political marketers do not always have the luxury of time or resources necessary for sophisticated testing. However, testing one subject line against another is simple to undertake and simple to evaluate. Considering that it impacts whether or not an email is opened, or delivered at all, this is advice worth heeding!
is CEO of American Information Marketing, LLC (“AIM”)
a database marketing company and new media agency providing
opt-in email addresses with turnkey deployment and tracking,
Tommi previously owner-managed a full-service political
marketing and fundraising agency in the nation’s capital.
Tommi can currently be contacted at Click here to contact this Author