Top Five Tips for Maintaining Email Deliverability

  • Posted: 18th December 2017
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Maintain and improve your Email Deliverability

I’ve been working in technical marketing for over 20 years and have focused specifically on email deliverability for the past five. I joined Celerity from Adobe and have worked on improving email deliverability for many global brands including Ford, GSK, Sky and Heathrow Airport.

1.     Creating and maintaining your recipients list

The first key tip for maintaining and improving deliverability lies within your list. There are many things you can do to improve the quality of your list for deliverability, but I have pulled out the following key steps you should be following:

Collect your own subscribers, don’t buy third-party lists.

Purchased email address lists often contain unverified email addresses. Obviously, sending emails to unverified addresses can lead to spam complaints or spam trap hits, both of which have a negative impact on deliverability. You should avoid purchasing data wherever possible and instead invest in building your list organically.

Use opt-in/double opt-in

When collecting email subscribers, you should request explicit opt-in and preferably ask for double opt-in. A double opt-in doesn’t just affirm intent of the subscriber, it also reduces the probability of adding bogus email addresses /spam trap email addresses to your list.

Send welcome emails

Sending a welcome email soon after a new recipient has subscribed shows that he or she is valued and can increase engagement rates for further email campaigns. Think of it like a great start to the new relationship between your brand and subscriber.

Segment your recipients list

Seems like an old one but I am constantly surprised how many people still do not segment their recipient list. You shouldn’t be sending the same email to all recipients. If you’re not sure where to start, try dividing your list into segments by activity, purchase history, or simply demographic.

Re-engage or remove inactive recipients from your mailing list

Sending regular emails to recipients who have been inactive for a long period of time will do little to re-engage them. Its different for each company, but if you have had no engagement for 10 emails, I say take them off.

You could try a re-engagement campaign with an offer or even just a note warning them you plan to remove them and ask if they are still interested in hearing from you; if there is still no reaction, take the recipients off the list. Sending emails to long term inactive recipients increases the risk of hitting spam traps or generating spam complaints.

Have a clear and simple unsubscription process

Using a clear and simple unsubscribe process prevents recipients from hitting the ‘Spam’ button when they don’t want to receive further emails. The number of unsubscribes in a campaign can be a really useful metric, whereas spam complaints are useless and negatively impact deliverability.

2.     Focus on Content

The content of an email message has a big impact on how deliverable it is deemed. Spam filters analyse content elements including the subject line, email text, URLs, and email header.

Good email practice comprises:

– Make sure the email content is relevant for the recipients
– Keep the subject line simple and short and avoid the use of spam words such as ‘100% FREE’ or ‘Save £££’
– Try to convey the content of the email and the most important call to action within the subject line
– Keep the email content consistent with the subject line
– Use clean HTML and ensure that the email renders well on different devices
– Avoid URL shorteners
– Check the content with a spam checker tool, e.g. Spam Assassin
– Try to fix any highlighted issues before hitting the send button
– Make use of A/B testing

3.     Sending volumes, times and number of emails

Large, sudden spikes in sending volumes can lead to deliverability issues, such as temporary rejections or rate limiting. Try to maintain a regular sending pattern without large deviations. If you have a particularly large campaign, try distributing the send over a couple of days. If you’re sending to a global audience, make sure you take into account the different time zones.

Don’t send too many emails to the same recipients. Sending a similar email several times a week can be annoying for some recipients and increases the risk of spam complaints. You should try and find the ‘sweet spot’ where the emails are not too often nor too few.

The most important thing? Test. Test. Test.
Create groups of recipients and test a variety in the numbers of emails, times, volumes etc. and see what works best.

4.     Analyse your metrics

A high ‘delivery rate’ only means that emails did not bounce, but does not guarantee that they were delivered to their designated inboxes. They could well have ended up in the junk folders.

The basic metrics marketers measure are open rate, click-through rate, bounce rate, and complaint rate. However, there are other metrics, such as spam trap hit rate and unsubscribe rate which I believe provide an even greater visibility on a campaign’s success. All these metrics can be used to optimise subsequent campaigns.

5.     Keep an eye on your reputation

Whilst email content certainly has an impact on whether an email is delivered to the inbox or to the junk folder, email service providers put far more weight on a sender’s reputation when deciding whether an email should be delivered to the inbox or to junk. The sender reputation has a direct impact on the inbox placement of the emails. There are many factors which impact an email sender’s reputation, such as open and click rates, hard bounces, spam complaints, spam trap hits, etc. and despite it taking weeks or months to build up a good sender reputation, it takes only a few ‘bad’ email campaigns to damage it. As it can fluctuate so easily, it is important you keep a close eye on it with regular checks.

We have a selection of products to help you audit, maintain and improve your deliverability rates – contact us today or email