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Cloud-based email services: Everything you need to know

Here's a compilation of what you need to know about selecting and using a cloud-based email service -- and, yes, you may not know everything.
Written by Chris Preimesberger, Contributor

Next to social networks and texting, email -- at about 293 billion sent per day -- is the most utilized cloud service in the world. Don't believe anybody who tells you that email is dead or dying. It's not, and it won't fade away for a long while -- it's too valuable a service, especially for business. Starting back in the mid-'90s with AOL, Yahoo, and Microsoft's Hotmail and continuing through the present time with Google's Gmail, Microsoft's Outlook, and a long list of others, free-of-charge cloud-based email has been a mainstay of daily work for more than a generation.

Email used to be a simple system to send messages over the internet instead of through the mail. Since its creation in 1971, email has been quietly moving into many aspects of our daily lives, such as automated notifications for medical and automotive check-ups, home security monitoring, and company collaboration. It's become a way of automating our lives.

Hosted commercial email services also use cloud connections and offer add-on services as needed by users mostly employed in enterprises. Here's a compilation of what you need to know about selecting and using a cloud-based email service -- and, yes, you may not know everything.

Data Point No. 1: Email using any kind of cloud exchange is separated from an enterprise's private communication infrastructure. 

InfoSec specialists prefer to distrust any outside service that carries a business's private information. This is why an increasing number of government, military, scientific, and highly-regulated enterprises are moving to private interconnect systems that operate outside the public internet. This isn't so much the case, however, with enterprises of all sizes. Using a publicly available cloud-based email service means that your ability to email and connect with your colleagues continues through the internet in the event an internal server fails. In contrast, a private exchange is built into the internal infrastructure, making workplace collaboration completely dependent on the internal connection. If the internal server goes down, so does email.

A benefit of hosting your own email is that messages are sent within the office, making the transfer a little quicker than with the cloud. With a cloud exchange, emails are sent outside the office for storage and are then brought back inside to the recipient's inbox, slowing down exchange speed. In addition to swift email transfer, private exchange offers settings to enhance workplace collaboration, such as setting custom email sending size and security restrictions. These settings are unique to private exchange and represent a glaring contrast to the one size fits all approach of cloud-based exchange.

Whether your business decides to use a private or cloud exchange, it's important to understand the upside and downside of each exchange system. Your business and day-to-day operations will determine which exchange is best for you. With the rapid development of this and edge computing, how will your business use email for optimal performance? That's the important question.

Data Point No. 2: Top five most-deployed free cloud-based email services

Chances are high that you use one of the following email accounts:

  • Google Gmail: It's reliable, quick-reacting, has plenty of options, and Is intuitive to learn. According to Androidpolice, Gmail is the most used service worldwide. As of early 2021, Gmail had about 1 billion registrants and 750,000 active users. Disclosure: Strings of email conversations can be hard to follow; it can take a bit of search to find the latest comments. Like anything else, the more one uses it, the more automatic the navigation becomes.

  • Microsoft Outlook: It's in second place with 400 million active users. It can be used independently from the Office 365 platform and has big advantage in that it is pre-installed in Windows PCs. It's very responsive and intuitive to use.

  • Yahoo Mail: No. 3 with nearly 230 million active users. Many of these are old-schoolers who started using Yahoo Mail back in the 1990s, when it and AOL owned the market before Google and Microsoft forged ahead in the early 2000s. Not known as the fastest-reacting email service in the past, it has made improvements recently.

  • Yandex Mail:Yandex is a popular search engine for news reading, claiming about 85 million monthly users.

  • Mozilla Thunderbird:  Thunderbird's team has been working to improve the service's user interface and UX, with better Gmail support and native notifications for Windows, Mac and Linux -- the three operating systems Thunderbird supports for its 25 million users.

Additional cloud email items: 

  • NetEase Mail: The Chinese internet company, born in 1997, mainly competes in the online gaming business but also provided email for a reported 300 million users in 2017. However, those numbers were difficult to verify. The company does see continuous strong growth in Asia in 2021, and the market estimates are that it now serves about 500 million users for games and email.

  • AOL: The iconic market leader in the early days of the internet is being phased out as Verizon sells its media assets to Apollo Global Management. But the iconic America Online brand, the gateway to the web in the 1990s, is officially no more. 

Data Point No. 3: Top commercial cloud email services

iCloud Mail

iCloud Mail is easy to use, reasonably priced with good storage limits, and has a useful web interface, which means it can be used on any device. It also has decent spam filtering and tight integration with Apple products.The cloud storage and cloud computing service from Apple Inc. launched on October 12, 2011. As of 2020, the service had an estimated 900 million users, up from 782 million users in 2016. A 5GB mail storage account is free of charge, 50GB is 99 cents per month, 200GB is $2.99 per month, and 2TB costs $9.99 per month.


Workspace (formerly G Suite) now has 2 billion users as of early 2021. Gmail is a central service. Google Workspace plans start as low as $6 per user per month for Business Starter, $12 per user per month for Business Standard, and $18 per user per month for Business Plus. 

Office 365 Microsoft Outlook:

According to Microsoft, Office 365 now has about 300 million monthly active users. Growth has remained constant at about 3 million users per month since November 2015. Users can share a Microsoft 365 Family subscription with up to five other people. Each person will use their own Microsoft account to install Office on all their devices and be signed in to five at the same time. Office 2019 Home & Business costs $249.99, up 9 percent from the $229 Microsoft asked for Office 2016 Home and Business. Office 2019 Professional now costs $439.99, up 10 percent from the $399 that Office 2016 Professional costed. Both of these can be used in commercial contexts.

Yahoo Small Business

Users can get a business mailbox starting at $3.19 per month in Yahoo Small Business. Five mailboxes cost $1.39 per mailbox, and the price goes down to $1.19 per box each for 10 users.

Zoho Mail

This is a secure and reliable business email solution featuring advanced collaboration features. A free forever plan is available, and the paid plans are competitively priced: 5GB ($1/month), 50GB ($4/month), 100GB ($6/month); all are billed annually. Users set up an email account through the Zoho Mail client, and the email is then sent through Gmail's server. Users get the ease of Zoho Mail and the security and storage space that comes along with Google Workspace.


This is strictly a business operation. Starting at $499 per month per server and capping at $1,249, Rackspace's dedicated servers are priced according to the server space users require. Rackspace account managers will assess the services required based on your business needs and recommend an hourly rate for your plan.

Data Point No. 4:  The most secure free cloud email providers

End-to-end encryption is provided by all of the following. List is by industry analyst PrivacySavvy.

  • ProtonMail:High-security cloud-based email provider. Per-user pricing is $6.25/month when paid annually, and $8/month when paid on a month-to-month basis.

  • Tutanota:Europe-based provider offering both individual and businesses accounts. Flexible pricing plans enable secure mailboxes with custom domain support starting at €1 per month.

  • Mailfence: Mailfence pricing starts at $2.50/month as a flat rate. There is a free version, and the company offers a free trial.

  • Hushmail: Encrypted email. One user costs $9.99/month with a 10GB storage capacity and up to five users cost $19.99/month with a 15GB storage capacity. The price and GB storage increases with the number of users. Companies with 100+ employees must contact Hushmail for a custom quote.

Email facts and statistics

Statistics, extrapolations, and counts by the Radicati Group found the following:

  • More than half of the world's population used email in 2020.
  • The number of worldwide email users is expected to grow to more than 4.3 billion by the end of 2023.
  • The total number of business and consumer emails sent and received per day exceeded 293 billion in 2019 and is forecast to grow to more than 347 billion by the end of 2023.

DMR has curated these other facts about email:

  • The first email system was developed in 1971.
  • Ray Tomlinson is generally credited as having sent the first email across a network, initiating the use of the "@" sign to separate the names of the user and the user's machine in 1971, when he sent a message from one Digital Equipment Corporation DEC-10 computer to another DEC-10.
  • The first email standard was proposed in 1973 at DARPA and finalized within Arpanet in 1977, including common things such as the to and from fields and the ability to forward emails to others who were not initially a recipient.
  • Each day, the average office worker receives 150 emails.
  • The click-through rate for email sent in North America is 3.1%.
  • The average click-through rate on desktop computers is 13.3% and, on mobile devices, it's 12.7%.
  • The average amount of overall emails opened on desktop computers is 16%, on mobile devices is 55.6%, and on webmail is 28%.
  • The open rate increases by 17% when the subject line is personalized.
  • Forty-two percent of Americans admit to checking email in the bathroom, and 50% do so while in bed.
  • The average open rate for retail emails is 20.96%, and for political emails is 22.23%.
  • The top spam content category in 2017 was healthcare, followed by malware.
  • The top reason U.S. internet users unsubscribe from email lists is: "I get too many emails in general."

According to Statista, the most popular email client is Apple iPhone, followed closely by Gmail

99Firms has its own curated list that includes the following facts:

  • Despite the rise of social messaging apps, 78% of teenagers use email.
  • A majority (62.86%) of business professionals prefer email to communicate for business purposes.
  • Ninety percent of workers check their personal email at least every few hours.
  • Email click rates increase by up to 300% if a video is included.
  • The best times to send email are between 10:00 a.m. and 11 a.m.
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