SMTP mail relay routes emails through a trusted third party to help deliver high volumes of email. It most often specializes in sending large batches of emails, such as newsletters, or automatic transactional emails, such as delivery confirmations and password resets.

Do I need an SMTP relay?

You need an easy way to send email from hardware like a printer, scanner, fax machine, or IoT device. Your ISP (Gmail) has put a cap on how many SMTP relays it can conduct per day, so you need an SMTP relay provider to help you deliver a higher volume of email without being mislabeled as spam.

When would you use a SMTP?

SMTP is used to send emails, so it only works for outgoing emails. To be able to send emails, you need to provide the correct SMTP server when you set up your email client. Unlike POP3 and IMAP, SMTP can't be used to retrieve and store emails. SMTP is also responsible for setting up communication between servers.