Mobile Subject Lines

Writing Subject Lines for Mobile Devices: What You Need to Know

Consumer shopping habits are no longer linear. Some people browse on their mobile phones and buy in-store. Others add items to their carts on their work computers but buy at home on their tablets. Some people research products online and then visit a store to see the merchandise in person before buying while others research in stores but buy online. There is no one direct sales path. But, there is also no denying that mobile shopping is on the rise. Just look at the effect it had this past holiday. Overall sales increased 4% over 2013, totaling $616.1 billion, but in-store sales decreased 8%. Online sales, however, increased a whopping 15% but mobile was the big star, increasing 27.2% and accounting for 22.6% of all online sales. It's also worth noting that 45% of all online traffic to retail websites came from smartphones and tablets between November 1 and December 31, a 25.5% increase over 2013.

The scales have also tipped in mobile's favor as Litmus recently reported that 51% of all emails are now opened on a mobile device.

What does this mean for your email messages? It's time to optimize your campaigns for use on mobile devices. Even if your website isn't responsive yet, your emails should be.

Subject Line Character Count

Subject lines are the first things the recipient sees and it determines whether or not the email gets opened so the importance of the subject line can't be over-stated! Different mobile devices show a different amount of characters, and the character count on each device will also differ depending on how the user holds it. The iPhone will only show about 35-38 characters in portrait mode but 80 in landscape mode. The Galaxy S4 shows slightly fewer characters – about 33 in portrait mode and 72 in landscape. An iPad will show 39 characters regardless of the orientation while the iPhone 6+ shows up to 63. Here's how the same Gmail inbox looks in both portrait and landscape, along with the desktop view for comparison:

Subject Lines

Keeping subject lines to 35 characters is tough but you should definitely try to do just that; or, at least keep your main message to 5 or 6 words and put it at the very beginning so it shows up on a mobile device.

Try to avoid subject lines that are too long – or at least put the most enticing part of the message first. In the examples below, the first 35 characters are viewable; however, the characters in red are not visible on most mobile devices:

How to leverage pre-header text

It is also important to note that the email pre-header text shows up under the subject line, so you want to be sure that pre-headers reinforce the subject and main message.

Pre-Header Text

You want to be sure to put the right message into the pre-header and avoid using messages such as:

While it is important to include this information, it should be included later in the pre-header so it doesn't take away from the limited space available on mobile devices.

Getting It Right

Here are some examples that really get the subject lines and pre-header text right:

Subject line: Have Sexy Shoes, Will Travel
Pre-header: Complimentary Shipping!

Subject line: The Spring Preview
Pre-header: Free Standard Shipping – No Minimum

Subject line: Shop Our Super Sunday Sale
Pre-header: Score Big Bargains this Weekend!

Subject line: Member's Only Pricing! 28% Off Sitewide.
Pre-header: 28% off sitewide

Subject line: Reversible Swim We <3
Pre-header: Free Shipping + Returns | Turn One Suit Into Two

Subject line: Something just for you!
Pre-header: New Spring Belts!

Subject line: The Magic is in the Makeup
Pre-header: Right before your very own eyes

Subject line: We <3 these gifts!
Pre-header: Shop our mobile site

What if your website isn't responsive?

More than half of all emails are opened on mobile devices and $1 out of every $10 spent in eCommerce comes from a mobile device. Even if your website isn't responsive yet, your emails should be.

In our recent research guide, we found that 16.5% of the Top 500 retailers and 16.5% of the Second 500 retailers currently have responsive sites, but only 6.4% and 3.8% have responsive emails, respectively. We also know that responsive emails work – even if the site isn't optimized for mobile devices.

Responsive emails have a 113% higher click-through rate on mobile devices than non-responsive messages. More importantly, we've seen mobile sales jump an incredible 2700% after implementing responsive designed emails even though the site wasn't responsive yet. This proves that you don't have to wait until your site is responsive before you implement mobile-optimized email messages.

If you're just getting started with responsive emails, here are some best practices to consider:

For more information and best practices, watch our webinar on demand "Always On: Connecting with Mobile Shoppers"