Gmail remains the world’s largest email provider in 2026, ahead of iCloud Mail, Outlook and Yahoo Mail.
Below, we break down the latest user figures, market-share data and email usage trends across the world’s biggest email platforms.
Key Findings
- Gmail remains the world’s largest free email provider with around 1.8 billion users globally.
- iCloud Mail is estimated to have around 950 million users, although this is based more broadly on Apple’s iCloud ecosystem.
- Outlook has an estimated 400 million users worldwide.
- Yahoo Mail still maintains a sizeable user base with around 225 million users.
- Proton Mail has grown to an estimated 100 million users globally.
- Global email users are forecast to reach almost 5 billion by 2028.
Contents
- Global Email User Growth
- Most Popular Email Providers
- Gmail Users
- iCloud Mail Users
- Outlook Users
- Yahoo Mail Users
- Proton Mail Users
- AOL Users
- GMX Users
- Zoho Mail Users
- Email Client Market Share
Global Email User Population: How Many Email Users are There Worldwide?
| NUMBER OF EMAIL USERS WORLDWIDE 2017 – 2028 | |
|---|---|
| Number of users in millions | |
| 2017 | 3718 |
| 2018 | 3823 |
| 2019 | 3930 |
| 2020 | 4037 |
| 2021 | 4147 |
| 2022 | 4258 |
| 2023 | 4371 |
| *2024 | 4481 |
| *2025 | 4594 |
| *2026 | 4730 |
| *2027 | 4849 |
| *2028 | 4970 |
| *2024 – 2028 are forecasted volumes | |
Key Trends
- Global email users increased from 3.7 billion in 2017 to 4.37 billion in 2023.
- Forecasts from Radicati and Statista suggest the figure will approach 5 billion users by 2028.
- Worldwide email usage is projected to grow by more than 1.2 billion users between 2017 and 2028.
What Is the Most Popular Free Email Provider?
| MOST POPULAR FREE EMAIL PROVIDERS | ||
|---|---|---|
| Provider | Launch Year | Users in Millions |
| Gmail | 2004 | 1800 |
| iCloud Mail | 2000 (iTools), 2002 (MobileMe), 2011 (iCloud) | 950 |
| Outlook | 1996 (Hotmail), 2012 (Outlook) | 400 |
| Yahoo Mail | 1997 | 225 |
| Proton Mail | 2014 | 100 |
| AOL | 1993 | 25 |
| GMX | 1997 | 20 |
| Zoho Mail | 2008 | 15 |
| MOST POPULAR FREE EMAIL PROVIDERS | |
|---|---|
| Provider | Percentage share |
| Gmail | 50.9% |
| iCloud Mail | 26.9% |
| Outlook | 11.3% |
| Yahoo Mail | 6.4% |
| Proton Mail | 2.8% |
| AOL | 0.7% |
| GMX | 0.6% |
| Zoho Mail | 0.4% |
Key Takeaways
- Gmail accounts for just over half of all users across the major free email providers analysed.
- Apple’s iCloud Mail remains the second-largest provider, although its figures are tied more broadly to Apple’s wider ecosystem.
- Outlook and Yahoo Mail continue to maintain sizeable global user bases despite increased competition from newer providers.
- Proton Mail has become one of the largest privacy-focused email providers, reaching an estimated 100 million users.
- Smaller providers such as GMX and Zoho Mail continue to operate with comparatively niche user bases.
How Many Gmail Users Are There?
1.8 billion
Gmail is Google’s email service and, according to statistics, has around 1.8 billion active subscribers in 2026. Google launched Gmail in 2004, and it has since become the world’s most widely used free email platform.
How Many iCloud Mail Users Are There?
950 million
Data is based on the number of iCloud users out there. However, not all iCloud users will necessarily use iCloud Mail. Apple’s email service started in 2000 as iTools, before a rename to MobileMe in 2002, and then Apple finally settled on iCloud in 2011. The service has an estimated 950 million users in 2026.
How Many Outlook Users Are There?
400 million
Microsoft launched its first email service—Hotmail—back in 1996 before later transitioning the platform into Outlook. Microsoft replaced Hotmail with Outlook in 2012, while allowing existing Hotmail users to keep their email addresses. Outlook currently has in the region of 400 million users worldwide.
How Many Yahoo Mail Users Are There?
225 million
Yahoo Mail remains one of the world’s largest free email services. It was launched by Yahoo! in 1997, with Verizon acquiring both AOL and Yahoo! in 2015 and 2017, respectively. The free Yahoo Mail service, as we know it today, has a total estimated user-base of around 225 million.
How Many Proton Mail Users Are There?
100 million
Proton Mail launched in 2014 (and so is the youngest of the email providers SellCell analysed). Proton Mail has continued to grow by focusing on privacy and encrypted email services, reaching an estimated 100 million users globally.
How Many AOL Subscribers Are There?
25 million
AOL was one of the earliest pioneers of consumer internet, and its free web-based email service—AOL Mail—is still going to this day (albeit with significantly less popularity). AOL launched the service in 1993 and it still has around 25 million active users today.
How Many GMX Mail Users Are There?
20 million
GMX is another multi-faceted provider, with just one of its services being free email accounts. It was launched in 1997. Estimates suggest GMX has around 20 million active users in 2026.
How Many Zoho Mail Users Are There?
15 million
Zoho provides a wide range of internet-related services, and Zoho Mail is just one of the tools users can gain access to. While anyone can access Zoho Mail, developers have designed it with business use in mind. This being the case, Zoho Mail has an estimated 15 million active users, which it has amassed since its 2008 launch.
Email Client Market Share
| TOP 10 EMAIL CLIENT MARKET SHARE (FEBRUARY 2026) | |
|---|---|
| Percentage share | |
| Apple | 45.51% |
| Gmail | 23.54% |
| Outlook | 5.67% |
| Yahoo Mail | 2.06% |
| Google Android | 1.34% |
| Outlook.com | 0.40% |
| Thunderbird | 0.17% |
| Orange.fr | 0.08% |
| Bell Email | 0.02% |
| Samsung Mail | 0.02% |
Apple Mail accounts for almost half of tracked email-client market share at 45.5%, while Gmail remains the second-largest email client globally with a 23.5% share.
Outlook’s overall market share remains comparatively smaller despite its strong position within business and enterprise environments.
Email Provider Trends
Gmail continues to dominate the global email market, while Apple and Microsoft maintain enormous user bases through iCloud Mail and Outlook.
At the same time, privacy-focused services such as Proton Mail continue to grow as encrypted and security-focused communication becomes increasingly important to users.
Methodology
User figures are based on a combination of publicly reported platform data, industry estimates and wider ecosystem figures where direct email-user numbers are not publicly disclosed.
Sources
- Radicati
https://www.radicati.com/wp/wp-content/uploads/2024/10/Email-Statistics-Report-2024-2028-Executive-Summary.pdf - Statista
https://www.statista.com/statistics/255080/number-of-e-mail-users-worldwide/ - Clean Email – Gmail, Outlook, Yahoo, Proton, AOL and GMX
https://clean.email/blog/email-providers/most-popular-email-providers - Capterra – Zoho
https://www.capterra.com/p/174694/Zoho-Mail/ - Litmus – Email Client Market Share
https://www.litmus.com/email-client-market-share