Deliverability: What It Affects

Deliverability is a bit of a black hole for most email marketers. It sounds messy and it's hard to understand.

This isn't without reason: it can be tricky to comprehend as it's a technical challenge. Deliverability refers to the rate at which your emails are actually reaching customers' inboxes. Assuming you are double opting-in customers and that you are at least asking their persmission to email them you should not have a hard time ensuring your emails don't bounce.

However, that doesn't mean they will actually head to the inbox rather than SPAM. There are three main things that affect deliverability:

  1. Email content. No matter what anyone tells you the actual content of your emails is extremely important in determining whether major email providers will flag you as spam.
  2. Complaint rates. If customers continually mark your emails as 'spam' with their mail provider, you will ultimately suffer heavily in your email reputation and future emails are less likely to reach the inbox.
  3. Email volume. This is a relative measure. If you sent 0 emails yesterdy and all, all of a sudden, send 10 million today this will reflect poorly on your domain and sending IP addresses. Smoothing your volumes and scaling slowly will be best for your long-term success.
  4. Domain configuration. Ensuring you have the correct DNS records setup will give you the best chance of having your emails reach the inbox.

The place to start when it comes to deliverability is to look at some data.

Sender Score is an online service maintained by Return Path that helps you track (with an individual number) the current reputation of your domain and IP address. Simply visit senderscore.org, enter your sending IP and see the results.

Mail Tester is a great (free) little tool that helps you to see whether your email content is likely to be marked as spam. Using a series of filters employed by SpamAssassin (a common spam filter) it will breakdown which components of your email setup are contributing to the success (or otherwise) of an inidivdual email campaign. This is a must-check for any new campaign you setup if you are trying to troubleshoot delvierability.