What is an SMTP Server?

Making sure your emails end up in customer inboxes is a crucial key to email marketing. Email deliverability is the extent to which your emails are properly delivered to subscriber inboxes. You might face many obstacles in your attempts to deliver emails, including being marked as spam, high bounce rates and negative sender reputations. As an email deliverability company, Inboxroad prioritizes the successful delivery of your emails to your subscribers. We have several posts outlining top tips to achieve great deliverability rates, as well as improve all facets of your email marketing campaigns.

Central to all of this is SMTP, or rather SMTP servers. This is where Inboxroad comes in. We are an SMTP relay service that specializes in the delivery of large quantities of emails for our clients. With this post, we would like to clarify what an SMTP server is and does.

What does SMTP stand for?

SMTP stands for Simple Mail Transfer Protocol, which translates to the internet-based process of email delivery. Mail servers apply this protocol to receive, send and relay emails between those who send and receive emails.

What is an SMTP server?

A simple mail transfer protocol server is the outgoing server that can be compared to a delivery person. The server carries your email, reads all the data regarding the message’s transmission – such as who the senders, receivers and domains are – and delivers your message to your recipient. This, for sake of clarity, is a simplified version of an SMTP server’s operations. In essence, an SMTP server is similar to most servers in that it communicates processed data to other servers. However, this type of server is particularly dedicated to the sending, receiving and relaying of email-specific data.

Inboxroad & PowerMTA

Inboxroad uses a more advanced SMTP server called powerMTA – or message transfer agent. PowerMTA is also increasing in popularity with many email service providers. The more specialized email delivery software is more suitable for high-volume email delivery, in comparison to normal SMTP servers. PowerMTA allows for greater control over your email sending, IPs and domains.

Additionally, a normal SMTP server makes use of just one sending IP, whereas a powerMTA accommodates the use of several IPs. Inboxroad is thus able to provide our customers with multiple IPs, should they require it. Overall, powerMTA is suitable for both small senders who desire one IP, as well as larger senders who seek more IPs to achieve high volume email deliveries.


At Inboxroad, we offer our customers the greatest amount of respect. Accordingly, we believe in providing customers with individually-tailored powerMTA set-ups to meet their needs. We also present our customers with exceptional customer support. The maintenance of personalized relationships is what we believe leads our clients to the achievement of successful email deliverability. Our powerMTA set-up enables you to create virtual SMTP connectors and send out numerous threads from your Campaign Enterprise. The combination of both powerMTA and Campaign Enterprise thus work together to increase your sending performance and help you achieve email marketing success.