Email deliverability is a broad topic. Trends change; but there are a few things to always consider which will help you with your campaigns. Whether you are just starting with email marketing or you are here to improve your current projects, this guide should help you achieve success.

Send emails to people who have requested to receive emails from you. This is the most important thing in email marketing. You may send emails to people who have directly requested to receive your messages and have consented to receive these messages from you.

If people want to receive emails from you, they will open them, they will click links in them or they will reply to them. If they are expecting communication from you, when the emails are sent to the spam folder, they will check this folder and move your message to the primary folder. All of these actions are very good in terms of engagement and will assist with establishing a good reputation between you and recipient servers. Better reputation = better delivery rates. It is as simple as that.

You may be tempted to send “cold emails”  to recipients that you have found on Linkedin, on various contact web pages or from purchased or borrowed databases. You may think “What is wrong or what could happen if I add these addresses to my list? If I send more emails, then more people will hear about my product!”. This is the wrong approach. You may be able to gather some opens, even a reply or two; but in most cases, people will open these emails only to click “Mark as spam”. A lot of people will ignore your emails or they will not see them because they will be placed in the junk folder. Recipient server filters will see little or no engagement, and future emails could be placed in spam folders because recipients didn’t engage with the email received from you. Large numbers of addresses gathered in this way may be invalid or turned into spam traps.

All of the things listed above will hurt your sender reputation and your delivery capabilities.

If you are using a third party Email Service Provider, you should validate your sender domain. This acts as a digital signature and permission from your side - basically you are saying “I trust Elastic Email and I am allowing them to send emails with my domain name”. To translate this for recipient servers, we use SPF and DKIM records. When we send an email with your domain name (eg. sample.com), the recipient server will look up your domain, see SPF and DKIM and say:  “sample.com says that Elastic Email can send emails with their name - all good!”.

If you do not have SPF (or badly configured SPF), the recipient server would say “Elastic Email sends with the sample.com domain name - but they didn’t allow that. This looks like spoofing. Let’s put that email in the spam folder, just in case”.

You can read more about this mechanisms here:

How to Verify Your Domain

Common SPF Errors

If a domain name ends up on a blacklist, generally, this means that something has gone wrong. Most likely the domain hosted a virus, it was a scam site or it was sending spam messages. It is a bad idea to use blacklisted domains as sender domains or to add links to that site - your emails could land in the bulk folder or they could be rejected.

Blacklist providers are not equal - in fact, there are a  few major players that are taken into consideration. Please see our guide.

Many small email providers use specific blacklist providers to filter out the email. Large players usually stick to their own filters and a small number of major blacklists like Spamhaus. If URIBl Black is able to spot a bad domain, then for sure Google and Microsoft filters are able to do the same.

Misleading your recipients can happen on many levels and this is another very important thing to keep in mind. Your content is very important - if your subject says one thing and your email content is about something completely different, then your recipients may be left unhappy. Upset recipients will more often click unsubscribe or report as spam button.

Make sure that your sender domain is a valid domain that the user can click and enter via an internet browser. If you send messages from a domain that shows a 404 error, then your email will look unprofessional at best - most likely your reader will treat it as untrustworthy.

The same thing applies to links - do not use link shorteners that obfuscate your URLs. Mailbox providers treat them suspiciously and some of the link shorteners may be blacklisted.

Do not use too many redirections in your links. While using Tracking URLs is a good and accepted method, redirecting the user from site to site several times is bad practice.

One thing that recipient servers like is stability. When you start sending emails, start with small volumes or try to segment your campaigns into smaller chunks - this will help to establish the reputation on the sender domain and correlation between your domain and the IP(s). Ramping up your volume step by step will cause recipient servers to better accept your sending. Regular sending can be helpful with increasing reputation - sending emails that cause spikes in volume can lead to throttling.

Pictures can say a thousand words, but if you have too many images in your emails, they may say nothing because email filters will put them into the bulk folder.

Always design your emails so they will look good even if the recipient does not allow images to display by default. Do not hesitate to add more text when necessary and always try to add the ALT= parameter which describes what is what in case of images are blocked.

Keeping a good email to text ratio also helps - mail filters will treat these kinds of messages better than others.

You should strive to create personalized content whenever you can. At the minimum, you could use your recipient’s first name in greetings or in the subject of your emails. This can easily be accomplished by using our merge fields functionality.

It does not have to end here - when you prepare newsletters or special offers, you are able to do a customized version for each subgroup of your recipients. Recipients are more willing to interact with emails that are created specifically for them. Use this solution to improve your delivery rates.