Linux Shared Hosting
With Linux Shared Hosting, we allow sending emails without SMTP authentication (Local Exim Relay) through phpmail() function. Alternatively, you can send emails with SMTP authentication by configuring the email client or via email script.
Windows Shared Hosting
With Windows Shared Hosting, you can send emails non-authenticated emails via IIS SMTP. If you wish to send SMTP authenticated emails, you can configure the email client on your local computer, or you can use any email sending script.
VPS Hosting
With VPS Hosting, you will have administrative access to your VPS. Hence, you are allowed to send both SMTP authenticated and non-authenticated emails. Be sure you don't keep your VPS as the open relay and don't send spam emails. It may cause your VPS IP address to get blacklisted in spam databases like SpamCop, SORBS, Spamhaus, URIBL etc.
Note: It is recommended to clean your email list before starting an email campaign to reduce bounceback. check out the best email validation service.
