Email Subject Lines: What Affects Your Open rate?

What are the best strategies when it comes to email subjects? What is the ideal subject length? Should it be personalized? These are some of the mysteries of the modern marketers.
Sophie Lamarche
1 May 2015
Omni-Channel Marketing Campaign
1 min 40
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What are the best strategies when it comes to email subjects? What is the ideal subject length? Should it be personalized? These are some of the mysteries of the modern marketers. If you did some research on the web, you have probably read different opinions and statistics. The reason is quite simple – Every company is different and its interaction with its target public is as unique. This is why we usually give the same answer when we are asked these questions: there is no miracle recipe. The best way to learn what works for you is to test it!

However, to satisfy those who enjoy numbers, here are some statistics from emails sent from our clients via the Openfield application in 2015.

Subject length

Email subject length

Open Rate by lengthClickthrough Rate by length

We can see from these statistics that the subject length has hardly any impact on email open rates. The highest open rate of 28.31% belongs to subjects between 50 to 74 characters while the lowest, close behind with 27.11%, relates to subjects containing less than 24 characters.

However, the click-through rate, calculated on delivered messages, shows a highest trend for either very short or very long subjects.

Subject personalization

Personalization Open Rate and Click-through Rate

The subject personalization slightly raises the email average open rate. Adding the first name or a personalized element in the subject line is a good way of getting your contacts’ attention, so hard to get these days. As you can see in this chart, the click-through rate also increases when the subject line is personalized.

Even if adding personalization to the subject line is a good way of improving your open rate, the most challenging remains to find the best subject matter. Enticing curiosity, creating urgency and announcing important information are some of many tricks to create efficient subject lines.

Happy testing!

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