Last week infobox, the DMA Email Council’s newsletter featured the UK launch of a free white paper on subject line length published by my company Alchemy Worx.

For those of you who haven’t had a chance to read it yet the main findings of the research were pretty startling and run counter to conventional wisdom.

The research suggests that although subject lines with 60 characters or less make more people open your message (the traditional view) these people are less likely to then go on and click on content or offers within the message than people who open an email with a longer subject line. More opens = less clicks! There seems to be an inverse relationship between opens and both click and CTO rates.

As you might expect, we monitor a large number of UK email campaigns, from a cross-section of sectors and companies including British Airways, figleaves, Apple, Amazon JD Sports and Reuters; so I thought it might be interesting find out what subject line lengths email marketers are using and was astonished to find out just how are following conventional wisdom!

Out of 700 subject lines we monitored in the last 90 days, the vast majority—87% of them — were under 60 characters in length. A further 7% fell into the ‘dead zone’ between 60 and 70 character where neither opens nor the CTO rate is optimized, and only 6% of the subject lines were over 70 characters long and therefore likely to optimize click and CTO rates.

Does his mean that everybody out there is only interested in opens and doesn’t care about clicks?  Perhaps we could conclude that email marketers, having extensively and regularly tested longer subject lines, know for a fact that they don’t work?

Somehow I think not.

What’s more likely to be the case is that as an industry we’ve done such a fantastic job of believing the hype that we have stopped testing outside of the accepted norms.

Our whitepaper also found subject lines with a higher word count also optimize clicks and CTO rates. So how do the numbers break down when it came to word count?

The numbers are equally amazing. Only 13% of subject lines monitored contained above 10 words—where clicks and CTO are optimized. 60% fell into the ‘dead zone’ of between 6 and 10 words, where neither clicks nor opens are optimized; and 26% of the subject lines contained fewer than 6 words, and therefore optimized open rates.

What I have learned from this exercise and would like to share with you all is that email marketers need to completely overhaul their subject line test strategy:

● Subject line tests should be more granular—long and short just isn’t good enough. Subject lines need to be broken down into more character groupings (1-10, 11-20, …91-100).

● Introduce word count testing. Words are a much better way of conveying meaning than characters.

● Assess the impact of the number of propositions contained in the subject line on your campaign performance.

● Finally, open rates are just a small part of the story. Your tests should assess the impact of subject lines on clicks, CTO rate and conversions, as well as sales.

My greatest fear is that the people reading the whitepaper will be looking for a simple answer such as “when it comes to email subject lines, short is best”, when in fact the central message is keep searching, keep optimising and keep on challenging assumptions.

Dela Quist
CEO
Alchemy Worx