sun with shades and an email envelope mouth

Summer Email Subject Lines: A Sizzling Strategy for 2021

The calendar has flipped to June. Marketers from coast to coast are staring out their windows trying to dream up summer email subject lines.

What’s the perfect combination of words to entice your subscribers to learn more? What’s going to increase your email open rates? How can you avoid the same old summertime puns and cliches everyone else is using?

While DJ Jazzy Jeff and the Fresh Prince would say:

"Summer, summer, summertime,

Time to sit back and unwind."

(Slightly ironic considering this song has been overused in summer subject lines for years. Still, a jam!)

The truth is, before you get to sit back and unwind, there’s work to be done. So, let’s take a strategic approach and dive into the summertime psyches of B2C email subscribers.

Why summer email subject lines matter

For many businesses, things slow down during the summer months. People are going on vacations and spending more time outdoors, which could mean they’re checking email a little less often.

Research shows eCommerce revenue takes a dip in the summertime (and not in the pool). Studies found sales can fall as much as 30% from their holiday highs in December, and average order values drop 5% below their annual average.

Many B2C brands will turn to the email team to help drive website traffic and give business a boost. That means you’re going to have even more competition in the inbox.

So, how are you going to make sure your summer email subject lines stand out?

We could give you another huge list of random summer subject lines to pick through for ideas. But instead, we’re going to give you the tools you need to write your own.

The power of “You” and “Your”

“You” is one of the most powerful words in copywriting. Whether you’re personalizing subject lines or not, using words such as you and your immediately makes it all about the subscriber and not just your brand, which is what you want.

Compare these summer subject line examples:
  • Jane, Our summer super sale starts today
  • Jane, Your chance to save starts today
  • See what’s in store for the summer season
  • You’ve got to see what’s in store for summer
  • A better summer begins with our new products
  • Your summer begins with these new products

Have you ever noticed how we think of the summer as “ours”? This time of year is so valued we feel as if it’s something that belongs to us. That idea could be some powerful subject line psychology. It’s your summer vacation, your barbecue, your sunburn … you get the point.

Don’t forget to put your subscribers at the center of summer email subject lines. It’s their summer. Reminding them of that idea is going to make them more likely to open your emails.

Summer FOMO

I grew up in Minnesota where the summer season was extra precious because we spent about half the year covered in snow, freezing our butts off. But no matter where you live, we all want to make the most out of summer, and we don’t want to miss out on any of the fun.

The “fear of missing out” (FOMO) is another useful tool for writing summer email subject lines.

There’s a lot going on between Memorial Day and Labor Day. People try to enjoy it as much as possible and choose the best events and activities. Likewise, subscribers will choose to open emails that promise to maximize summertime opportunities.

Consider these summer subject line examples:
  • Jane, Your summer savings will disappear soon
  • Don’t miss the sweetest summer deals of the season
  • Join the party and get the most out of summer
  • You’re invited to our summer event
  • What everyone is ____ this summer

FOMO works well in all sorts of email campaigns. But consumers may have a heightened sense of that feeling this time of year.

Summer email subject lines and emojis

Smiley Face - Emojis and summer Email subject lines

Using emojis in email subject lines could help campaigns stand out in the inbox. However, the email marketer from Search Engine Journal makes a good point. Emojis may catch a subscriber’s eye, but that doesn’t necessarily mean people will open the email. F-bombs in subject lines are eye-catching too, and you probably don’t want that.

Summer = fun, and emojis are fun. So don’t be afraid to sprinkle a few into some of your more lighthearted summertime email campaigns. From the shining sun and a smiley face with shades to tropical drinks and fireworks -– there are plenty to choose from. Check out the summer selection on

Just don’t overdo it. If every other email you send has an emoji in the subject line, the novelty will wear off, and it could get annoying. That’s why, as always, it’s smart to split test. How does your list react to emojis in subject lines?

Summertime holiday subject lines

Holidays and special events could present an opportunity to dress up summer email subject lines with an emoji or two. You can use our other subject line strategies with summer holidays as well.

Choose phrases that include “your dad” in Father’s Day email campaigns or “your kids/students” in school-related emails. Create a sense of FOMO around summer’s biggest days.

Here are some major summer events that you could connect to an email campaign:

  • Memorial Day (Last Monday of May)
  • End of the school year
  • Flag Day (June 14)
  • Father’s Day (third Sunday of June)
  • Juneteenth (June 19)
  • Summer Solstice (June 21)
  • Canada Day (July 1)
  • Independence Day/4th of July
  • Back to School
  • Labor Day (First Monday of September)

Be sensitive and respectful of the fact that some of these holidays are connected to serious history. Don’t exploit or trivialize things that are important to people.

There are also plenty of lesser-known days that fit the summer theme. That includes fun stuff like National Bikini Day (July 5), National Hot Dog Day (July 14), and National Rollercoaster Day (Aug. 16). Check those calendars for days that could relate to what your brand offers!

Summer clichés: Use them or lose them?

There will be an endless supply of cliché summer sayings landing in the inboxes of your subscribers. Is that because they’re lame, or is it because they’re effective?

A cliché becomes a cliché because it is recognizable and relatable. But often, they’re also a bit overused. Sticking one in your subject line may even feel lazy and uncreative. Then again, your list may love it. A/B testing subject lines with and without cliches might tell you more about what your subscribers think.

Here are some common summer phrases:
  • Beat the heat
  • Dog days of summer
  • Fire up the grill
  • Soak up the sun
  • Blazing hot
  • Christmas in July
  • Jump into summer
  • Cool off with …
  • Take a dip
  • Summer in the city
  • Hello, sunshine
  • Midsummer madness
  • Farewell, summer

Use these at your own risk. You might boost open rates, or you might boost eye rolls for using the exact same saying as another brand.

Another option is to use a few summer-themed pop culture references in subject lines. This is one of my favorite ways to make subject lines fun and relatable. Think of summer songs, song lyrics, and movie references or memorable lines.

Consider these pop culture references for summer emails:
  • We know what you did last summer
  • Summertime and the livin’ is easy
  • The Endless Summer
  • Wet Hot American Summer
  • Summer breeze makes me feel fine
  • Watermelon sugar
  • School’s out for the summer
  • We’re having a heatwave

Of course, since these come from popular culture, there’s still the chance someone else will have the same idea. So instead, you could zig whenever one else is zagging. Try flipping the summer subject line on its head and test options like “Not another summer email!”

End of summer urgency

A sense of urgency is a close cousin to FOMO. But rather than missing out, this subject line strategy is about time running out.

It’s a feeling that must’ve been baked into our brains as kids, dreading the end of summer and the return of homework. Now as an adult, at some point in August, you realize your summer days are numbered and you forgot to do all the things.

Use those feelings to your advantage and generate emotional subject lines that encourage subscribers to open emails and take action.

Consider these summer subject line examples:
  • Squeeze the last drops of fun out of summer
  • Don’t let your summer slip away!
  • Summer is almost over, and the heat is on
  • Your last chance for summer savings
  • Summer is short. Get your XXX before it’s over!

Hot tip: adding a countdown timer to these emails would complement this sort of subject line nicely!

Enlisting the help of preheader text

You can only say so much in a subject line. That’s why you’ve got to take advantage of the extra space the email preheader or preview text provides.

Preheader text is additional copy that appears right after the subject line but is only viewable in a subscriber’s inbox – not after they open the email itself. It informs contacts as to what they’ll find inside your email, but it can also work as an enticing tease.

For example, if you write a short and snappy summer subject line, the preheader text gives you the luxury of saying more and convincing subscribers they should see what’s inside the email. You can get really creative with ways to use preheader text to boost open rates.

Essence of Email’s article on subject line and preheader pairings has some great examples of how these two elements work together:

Subject Line: Summer dress code.

Preheader: Take your pick from our bouquet of charming summer styles. Click here to view it online

Subject Line: Do you like it shirty?

Preheader: We bet you do! Here’re 6 summer shirt icons you need to know about

The first example uses a CTA within the preheader text. The second turns the preheader into a continuation of the subject line with a fun question/answer format.

Optimize inbox display for summer email campaigns

Finally, after you spend the time to craft the perfect summer email subject lines, make sure they’re optimized for every inbox before you hit send.

Take a close look at the subject lines and preheader examples from Essence of Email below:

preheader text copy mistakes
Courtesy: Essence of Email

Yikes! That’s embarrassing (and kind of hilarious). But you can catch problems like this before your subscribers see it.

It’s important to remember that different email clients and devices will display your subject lines differently. It’s exactly why Email on Acid’s Inbox Display feature in Campaign Precheck is so helpful. You’ll be able to see how your subject line and preheader text will display on different clients as well as many different mobile devices.

The perfect summer subject line is only perfect if it shows up in the inbox exactly as you planned. Email on Acid is here to simplify that step and many other complexities of email marketing. Give us a try today and start delivering email perfection!

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