⚡ Webmail in the United States

Webmail software lets users access and manage email directly through a web browser.

The United States of America (USA) is a North American country with a population of over 341 million people.

According to our statistics, webmail software is used on 0.01% of websites from the United States.

⭐ Most Popular in 2026

The following chart shows the top webmail software in the United States in 2026, based on market share.

The most popular is Outlook on the web with an impressive share of 49.2%, followed by Roundcube with 35.6% and Mailcow with 6.8%.

🚀 Highlights

Here is a list of the top software that is more popular in the United States than worldwide.
Differences between global and country rankings are shown in parentheses.

✨ Best Webmail Software

Below is a more detailed list of 7 webmail software solutions used on sites from the United States, ranked by their market share.

RankNameMarket share
1
Outlook on the web
Redmond, Washington, United States

A web-based app included in Microsoft 365 that allows users to access their email, calendar, and contacts.
2
Roundcube

A browser-based multilingual IMAP client.

FreeOpen source$$$
3
Mailcow
Willich, Germany

An open-source groupware/email suite based on Docker.

FreeOpen source
4
Horde
Atlanta, Georgia, United States

An open-source web-based groupware.

FreeOpen source
5
SquirrelMail

A webmail client written in PHP that includes support for IMAP, SMTP, and a flexible plugin system.

FreeOpen source
6
RainLoop

An open-source, web-based email client that is no longer being maintained.

FreeOpen sourceLegacy
7
SnappyMail
Bilthoven, Netherlands

An open-source web-based email client forked from RainLoop.

FreeOpen source

👉 See Also

Data is based on the analysis of 545,779 websites from the United States.
Statistics were last calculated on .
For details, see our methodology and disclaimer.