Introduction
Newsletters, outreach campaigns, and transactional emails can all be vital parts of any business. However, these use cases usually do not fall under "real, human correspondence" for most email providers which can be a violation of policy if you engage in them. This is where SMTP relays come into play and allow you to send out these types of messages without affecting your email hosting.
What's SMTP?
Simple Mail Transfer Protocol (SMTP) is a protocol that allows the transmission of email messages between machines. Essentially, this is the way different computers and servers are able to send and receive mail from each other. Note that "receive" in this context is simply referring to the actual receipt of mail and not it's storage or access. When it all boils down, SMTP is how you are able to send mail to recipients.
How is an SMTP relay different from email hosting?
An SMTP relay only supports sending mail through the SMTP protocol. These services focus on delivering your messages to a large number of recipients but have nothing to do with receiving, storing, or accessing messages. If you want your recipients to be able to send you messages and reply to your outreach, there will need to be a real mailbox behind your address that can receive mail and store it for you to access. This is what an email host like Mango Mail does. Your email host is where your true mailbox and data lies. The email host also provides you with many protocols to read, access, manage, and send your mail (including SMTP). However, email hosts must be especially weary of spam and abuse. As such, email hosts do not allow for mass messaging on their servers since it's usually indicative of abuse. So if you have legitimate use case for sending large amounts of outbound mail, your best bet is to combine your email host with an SMTP relay service.
How to connect an SMTP relay to your email host
Getting your SMTP relay to work with your email host is usually a straightforward process since these two services go hand-in-hand. Typically, you'll first want to set up your email host. Then, you'll need to add or modify a few DNS records to enable the SMTP relay:
- DKIM Keys: DomainKeys Identified Mail (DKIM) is a security measure that ensures email content was created by the claimed sender. Mango Mail implements this by default, but in order to enable it for your SMTP relay, you may need to add more keys to your DNS provided by the SMTP relay.
- SPF: Sender Policy Framework (SPF) indicates which servers are allowed to send your mail. Your SMTP relay will require you to add their servers to your existing SPF record to allow them as valid sending servers. Make sure your SPF record includes both your email host and SMTP relay to allow them both to send.
- DMARC: Domain-based Message Authentication, Reporting, and Conformance (DMARC) enforces the previously mentioned SPF and DKIM security polices. This tells recipients how to respond to mail that fails these security measures. Mango Mail enables this by default when you set up your domain, so you should already be good to go.
Benefits of using an SMTP relay
- Isolates Reputation: Since an SMTP relay sends mail from servers that are separate from your email host, your email reputation for messages you send from your email host will not be affected by the campaigns you run on the relay.
- Better Mass Delivery: SMTP relays are fine tuned for delivering mass messages. This makes them better for delivering automated messages to your recipients.
- Recipient List Organization: Relays and newsletter services typically allow for organizing multiple large lists of recipients for different campaigns and target audiences.
Conclusion
Now that you've learned how to combine your email host with an SMTP relay, you can properly deliver your email campaigns, transactional messages, and outreach programs without eating up your email host rate limits.