Before we go into the VPS hosting list that provides open port 25, let’s see why we need open port 25 & why this port is blocked by many hosting providers.
Why do we need open port 25?
Port 25 is an SMTP (Simple Mail Transfer Protocol) port, or in other words, port 25 is used to send emails out and to receive emails as well. Just like you need port 80 to be open in order to access any website, you need port 25 to communicate with another mail server.
Now, here I would like to clarify one important thing. Port checker tool like yougetsignal tells whether the port is open for incoming traffic or not. In other words, if it tells the port is open, this means emails can reach your server. Therefore you can receive emails.
But this doesn’t mean you can send emails too. And this is not blocked by any service provider as per my knowledge. What is blocked is outgoing traffic. This means you can’t send emails out of the server. I hope now you are very clear about the concept.
- Port 25 open for
- Emails can be sent
- Emails can be received
- Outgoing Traffic
- Incoming Traffic
Why VPS providers block port 25?
Nowadays, spamming is a very big issue. Every month around 300 billion emails are exchanged and out of that around 250 billion emails are spam. Therefore, in order to protect users from unwanted emails, ISP started blacklisting servers involved in spamming. There is also 3rd party spam monitoring agency that notifies ISP of spamming from the server and subsequently gets blacklisted.
Apart from that, blacklisted IP lowers the reputation of VPS providers and therefore affects sales. Also, sometimes the whole subnet gets blacklisted i.e. all 256 IPs.
Not only that, the law enforcement agency of the country can accuse/arrest the hosting provider for assisting in the spread of spam.
Therefore, the VPS provider in order to save their infrastructure from being abused simply blocks port 25. This means no emailing.
We know email marketing is very powerful in today’s interconnected digital world. The outright ban by VPS providers is hurting email marketers. Bulk email marketing service providers like Aweber, MailChimp, Sendgrid, etc., though efficient and powerful can be quite expensive. Therefore, self-hosted emailing infrastructure is the only solution.
Here, I have listed VPS hosting which provides open port 25.
Note: This is the list as of writing is up to date, but from time to time VPS provider can change their policies. Therefore, I request all readers of this article to email me (firstname.lastname@example.org), if you find any hosting listed below is no longer selling VPS with open port 25.