The Ins and Outs of SMTP Relay Service

Thinking about SMTP relay service for your organization? Here’s what you need to know about it before you commit.

Email marketing takes a lot of resources to pull off. Naturally, you want to have an email service that enables you to reach your intended audience.

You may find that emails sent from your current provider are often flagged as spam. To avoid this, you should look into SMTP relay service, which can deliver your emails more reliably.

In this article, we discuss SMTP relay service and related subjects you should know about before you choose a provider.


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Open mail relay

Open mail relay is also known as insecure or third-party relay. This is the service an SMTP server provider offers. This means that emails from both your internal and external networks are sent on your behalf by this third party.

The opposite is closed mail relay. This is where only internal messages are sent. By nature, this is more secure, since it’s restricted to a closed pool of users; whereas with open mail relay, technically anyone can access it.


SMTP relay service: Google

Google is a big name in the tech industry, so it should come as no surprise that they have their own outbound SMTP relay service. Below are a few ways you can use their SMTP server for your organization’s benefit.

SMTP relay service: G Suite

Google offers a free SMTP relay service that’s perfect if you don’t need to send a large volume of emails per day. With 100 free daily emails, your business can utilize this free service while you search for a better provider.

SMTP relay: Office 365

You can use Google as an SMTP host to send emails through your multifunction devices or apps. This can be useful when you want to send scanned documents to yourself, your colleagues, or clients.

You can also use the SMTP relay: Office 365 for line-of-business (LOB) apps to streamline how you use your client database. For example, you can tap into your data and send out reminders to your clients whenever they have appointments.


Use the right SMTP port

When using any type of SMTP service, you always have to make sure you use the right SMTP port. If you fail to do so, it can result in undeliverable emails, which can create obstacles in your email campaign.


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Gmail outgoing mail server

With an SMTP server, you’ll have to keep in mind that the provider will only take care of outgoing mail. This means that when you’re using a Gmail outgoing mail server, or any other provider, the only related server involved is SMTP.

POP3 port

On the other side of things, when you receive email, this is handled by either the IMAP or POP3 server. While SMTP servers typically use port 25 or 587, the POP3 port you’d use is 110. Make sure these numbers aren’t mixed up, as it would cause deliverability issues as discussed above.


SMTP relay software

Because it sounds so simple, you may want to relay your emails yourself. However, this can be difficult to do without a third party helping you.

Firstly, you won’t have a powerful enough server to send your desired number of emails. Secondly, even if you had the capacity to do so, there’s a high probability that your emails will be marked as spam. When this happens, your sending reputation will fall, resulting in even more emails landing in spam folders.

If you want to get SMTP relay software, look into a managed SMTP server provider. Your emails won’t be filtered or marked as spam, plus you can maintain your sending reputation while sending bulk emails.


Free SMTP server list

If you want to try a free SMTP provider before you put down money for smtp relay service, there are quite a few choices out there. As mentioned before, Gmail is a well-known free SMTP gateway that gives you 100 emails per day.

If you’re not a fan of Gmail’s free SMTP server, there are other options available, such as:

  •       MailGet
  •       SendinBlue
  •       Moosend
  •       Amazon SES

However, we don’t recommend going down the free route, at least not for long. These free SMTP servers can still get you blacklisted, which can cause major deliverability problems in your campaigns.

By enlisting the services of a reputable third-party SMTP server provider, not only can you get outbound mail delivered reliably, but you can also protect against malware.

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