Security is our major concern and giving our phone number on every signup and account creation really raises our concern about security. So everybody looks for an email that doesn't require a phone number. Many websites like Gmail fulfill this requirement of yours. The process for signing up for Gmail is very easy and it is a free email sign-up without a phone number.
There are many other websites that serve the same purpose of free email creation without phone numbers like Tutanota, Portonmail, Mail.com, GMX mail, etc. Many of these websites provide subscriptions monthly or yearly for fully enjoying their services. However, you can also choose their free plan where users can enjoy free e-mailing services other services also but to a limited extent.
There are other mail services like “Email On Deck”, that let you make a temporary free email sign-up without a phone number. You can use this temporary email only once and after the use, it will automatically be discarded and cannot be reused.
There is also one more category of email service that is the public email, like Mailinator, Mailnesia, Tempinbox, etc. As these are public emails, you can make your own account or take over others’. Although despite providing free email service there is a huge drawback of these, that they do not let users send an email, you can only receive email through them.
See also - https://bit.ly/2NSH0Xq
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