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[Infographic] The 2019 Email Client Market Share


Edit: Take a look at our latest 2020 Email Client Market Share infographic.

Over the course of the past year, we’ve analyzed over 10 billion—yes, that’s billion with a “B”—email opens tracked with Litmus Email Analytics to see where subscribers read emails. And while a few things stayed the same, we saw plenty of movement this year in terms of email client popularity. In our 2019 Email Market Share infographic, we take a look at mobile, webmail, and desktop opens over the course of the year, providing insights into why these changes occurred and how they may affect your email campaigns.

To get a full, in-depth picture of where, how, and when people engage with email download our 2019 State of Email Engagement Report.

Check out the infographic here, or read the transcription below it.

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2019 email client market share


2020 State of Email Engagement

What else did we learn from analyzing billions of email opens?

For the latest research on email client market share and an in-depth look at when, where, and how people engage with email, download Litmus’ 2020 State of Email Engagement report. Use these insights to benchmark your email performance against your peers and learn how to turn engagement insights into strategies and tactics that improve your email program.

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Transcript: The 2019 Email Client Market Share

We tracked more than 10 billion email opens in the past year to determine where subscribers are reading emails. Here’s what we found…

If we looked at each email we tracked for just one second, that would keep us busy for about 330 years.


The top 10 most popular email clients as of April 2019

Ranking compared to April 2018

  1. Gmail, 27.8%
  2. Apple iPhone, 27.6%
  3. Outlook, 9.1%
  4. Apple iPad, 8.5%
  5. Apple Mail, 7.5%
  6. Yahoo! Mail, 6.3%
  7. Google Android, 2.5%
  8., 2.3%
  9. Samsung Mail, 1.6%
  10. Thunderbird, 0.5%

For the first time ever, Gmail is leading the global email client market share.

Outlook grew to be the #3 most popular email client, up from #5 a year ago.

Yahoo! Mail has climbed up three spots, now ranking #6 in the email client market share.

Optimize your emails for Gmail, the world’s most popular email client

With a number of big updates to Gmail—including the revamped Promotions Tab and the launch of AMP for Email—Gmail is offering marketers new opportunities to stand out in the inbox. That and the increasing popularity of Gmail among consumers makes this email client the #1 inbox provider for email marketers to look out for.


Even though mobile opens fluctuated a bit throughout the year, mobile remains the most popular reading environment with 42% of all emails being opened on smartphones or tablets.

  • Mobile clients accounted for 41.9% of email opens in Q1 2019 (up from 41.4% in Q2 2018)
  • Webmail clients accounted for 39.9% of email opens in Q1 2019 (down from 44.3% in Q2 2018)
  • Desktop clients accounted for 18.2% of email opens in Q1 2019 (up from 14.3% in Q2 2018)


Apple’s iPhone continues to be the undisputed leader in mobile email. About 28% of all email opens happen on iPhones, and an additional 9% come from Apple’s iPad, the #2 most popular mobile email client.

  • Apple’s iPhone accounted for 28.4% of email opens in Q1 2019 (up from 26.6% in Q2 2018)
  • Apple’s iPad accounted for 9.3% of email opens in Q1 2019 (up from 8.6% in Q2 2018)
  • Google Android accounted for 2.3% of email opens in Q1 2019 (down from 2.4% in Q2 2018)


About 40% of all emails are opened in webmail clients. Gmail holds the undisputed leadership position in webmail opens, outperforming other webmail clients by a long shot.

  • Gmail accounted for 26.2% of email opens in Q1 2019 (up from 24.4% in Q2 2018)
  • Yahoo! Mail accounted for 6.6% of email opens in Q1 2019 (up from 1.4% in Q2 2018)
  • accounted for 2.4% of email opens in Q1 2019 (down from 3.0% in Q2 2018)

Why that jump in Yahoo! Mail opens?

Verizon Media started merging the infrastructure of their email services—Yahoo! Mail, AOL, and Verizon—in 2018. Now, opens in any of the three email clients are being reported as Yahoo! Mail opens, making it the second most popular webmail environment.


Desktop opens have grown in the past year. In Q1 2019, 18.2% of all emails were opened on desktop email clients, up from 14.3% in Q2 2018. And it’s one email client in particular that drives the growth of desktop opens: Outlook!

  • Outlook accounted for 9.2% of email opens in Q1 2019 (up from 6.6% in Q2 2018)
  • Apple Mail accounted for 7.8% of email opens in Q1 2019 (up from 6.9% in Q2 2018)
  • Thunderbird accounted for 0.5% of email opens in Q1 2019 (up from 0.01% in Q2 2018)
  • Windows Live Mail accounted for 0.5% of email opens in Q1 2019 (down from 0.6% in Q2 2018)

Outlook on the Rise

Outlook opens have shown steady growth since 2017 and now account for more than 9% of all email opens. This makes Outlook the most popular desktop email client—now ahead of Apple Mail—and the #3 most popular email client overall.

Get an in-depth look at the 2019 State of Email Engagement

For the full research on 2019 email client market share and an in-depth look at when, where, and how people engage with email, download Litmus’ first-ever State of Email Engagement report.

Get your free copy →

Your Subscriber Base Isn’t The Average

Email client usage differs from industry to industry and from brand to brand. Wondering how your subscribers open their email? Find out with a free trial of Litmus Email Analytics.

Learn more  → 

Where did we get all this data? Our 2019 market share data is derived from over 10 billion opens collected worldwide with Litmus Email Analytics between April 1, 2018 and April 1, 2019. It highlights worldwide trends across all industries and verticals. Some email clients may be over- or under-represented due to image blocking.

Litmus accelerates your business with advanced email tools that empower your team to deliver the best brand experience and get the best results.