How the MailPoet Sending Service Helps You Avoid the Spam Box

Illustration by Mary Delaney illustration of an origami bird amongst flowers

If you aren’t familiar with the infrastructure underlying email technology, you might wonder – how exactly does it all work? Specifically, you might wonder – what is the MailPoet Sending Service? And why should you use it? But, above all – why is a sending service necessary in the first place?

The short answer is: the MailPoet Sending Service (and other sending services like it) helps your emails arrive in the inbox and not the spam box. In this post, we’ll walk through the basic concept of a sending service, explain how they work, and give you a behind-the-scenes look into the MailPoet Sending Service.

The problem: Your emails go into spam

For many years, the standard way of sending emails was via your web host. Indeed, even today, this is the “default” way of sending emails via WordPress. Many users, upon installing MailPoet, will simply opt for the default option of sending with their web host.

Unfortunately, spammers abused this situation (as they abuse everything!) and these days, sending with your own host is not a particularly great idea. Why? In short, your emails will be more likely to end up in spam (or never arrive at all). In fact, email service providers tend to stop emails before they even make it to the spam box.

Because spammers have used (and continue to use) web servers to spam, those sending with shared web servers have a bad sending reputation. As the servers are shared, it’s very likely you will eventually have sending problems.

For example, another person on your server might be a spammer, or at the very least, have a bad sending reputation. Spammers often hack legitimate accounts in order to send their emails, so even if you’re A-OK now, you still run the risk of having future problems. Ultimately, web hosts are in the business of hosting – not emailing. As such, they generally aren’t overly concerned with their sending reputation.


You can see the results of this yourself if you run a test at, a tool we built ourselves. If you’re using a shared web host, you run the risk of getting a very low score, even with popular hosts like GoDaddy, HostGator, DreamHost, or Bluehost. Alternatively, using a sending service (like the MailPoet Sending Service), you’ll get a higher score. Note that Mail-Tester only checks public blacklists – Gmail and other email service providers have their own private blacklists. As such, don’t rely on it entirely to gauge your sending reputation.

If you have a dedicated host (with a dedicated IP address), you will have less issues with reaching the inbox than someone on a shared host. However, properly managing a dedicated host for sending emails requires fairly technical knowledge and a not-insignificant time investment.

The solution: The Managed Sending Service

What’s the solution to this spam problem? The “Managed Sending Service.” To put it simply, managed sending services help your emails go into your subscribers’ inboxes.

We also recommend using a managed sending service in our definitive guide to newsletters in WordPress.

There are many companies in this space, including MailChimp, Constant Contact, AWeber, Campaign Monitor, and of course, MailPoet. Each service has particular features, benefits, strengths, and weaknesses, but in general, the underlying sending infrastructure is roughly equivalent.

The MailPoet Sending Service (MSS)

Enter MailPoet. For most of our plugin’s history, we didn’t have our own sending service. Typically, we recommended using a third-party service (like SendGrid) rather than the standard PHPMail web host option.

In 2017, we built and launched our own in-house sending service. In non-technical terms, the MailPoet Sending Service will deliver your emails your subscribers’ inboxes quickly, reliably, and efficiently. So far, we’ve got some pretty impressive stats:

  • We send nearly 1,000,000 emails per day
  • Our largest sender has a list of over 175,000 subscribers
  • Our delivery rate for last month (March 2018) was over 97.5% (0.5% were hard bounces and 0.40% we marked as spam)

From the source: A developer answers questions about the MailPoet Sending Service


To help us answer some more technical questions about the MSS, we talked to Tautvidas Sipavičius, a developer here at MailPoet:

Kiefer: Why did we decide to build our own sending service?
Tautvidas: We wanted to be in control over the service we provide, and to be able to seamlessly integrate it with the MailPoet 3 plugin, making it easy for our customers to use the service. With a third-party sender, you (the user) still have to manage some things (e.g. bounces). We take care of that automatically.

We wanted to be in control over the service we provide, and to be able to seamlessly integrate it with MailPoet 3 plugin.

Deliverability and list cleaning

One of the biggest problems facing senders is deliverability and list management. Over time, lists become “less clean” – domains expire, email accounts are changed, and so on.

If you send an email and it isn’t delivered, it is known as a “bounce.” When you repeatedly send to bounced addresses, your sender reputation is negatively affected. As such, if you don’t manage your list properly, your deliverability will slowly get worse and worse, until you may be tagged a spammer. Luckily, MailPoet (and many other sending services) automatically clean lists for you.

Kiefer: How does the MSS keep lists clean automatically?
Tautvidas: Email lists become “less clean“ as time goes on – some domains expire, email accounts get deleted, the owner may no longer want to get emails from you and mark your email as spam, and so on.

The MSS helps keep lists clean by periodically synchronizing bounce information with the MailPoet 3 WordPress plugin. If we notice that an email address cannot be delivered to (e.g. the inbox does not exist), MailPoet 3 will mark that email address as bounced. And the next time you send a newsletter with MailPoet 3 – the bounced email addresses will be ignored, and emails will be sent only to good addresses.

Sending emails at super-lightning speed

If you’re already a user of the MailPoet Sending Service, you might have noticed how ridiculously fast it is. Sending to a list of over 20,000 subscribers only takes about 15 minutes. How does it send so quickly?

Kiefer: How is the MSS so fast? What’s the “secret sauce”?
Tautvidas: The secret sauce is: batched emails. Normally, if you send emails with MailPoet 2 or MailPoet 3 via your host, emails will be sent one email address at a time. If you send to thousands of email addresses, or have a limit on how many emails you can send in an hour, it will naturally take some time.

The secret sauce is: batched emails.

Sending with the MSS is faster for two main reasons: firstly, because we do not enforce any limits to how many emails you can send in an hour. Secondly, MailPoet 3 can send emails with the MSS by sending batches of 20 emails at a time. Doing so allows for faster processing and eliminates the extra delays of having to connect to a remote server multiple times. We wouldn’t be able to send this quickly if we relied on a third-party sender’s infrastructure.

Feel like a Sending Service expert? We hope so! If you have any questions or concerns about the MailPoet Sending Service (or about email infrastructure itself), let us know in the comments!