Improve Your Deliverability

Make sure to optimize your email content for deliverability

Deliverability is a growing concern among email marketers, and one of the main barriers to an effective marketing strategy. Along with sender reputation, contact list, and sending frequency, email content is one of the main factors that impacts deliverability.

Before trying to create email content that converts, marketers should first focus on optimizing it for deliverability. Simply put, if the email content never lands in the inbox, there’s definitely no chance that your subscribers will open and click on the CTA buttons of your email campaigns. 

How to optimize your email content to improve deliverability

Some content habits generate higher complaint rates and poor interaction. This has a negative impact on sender reputation, and ultimately on the deliverability of future messages. To be recognized as a legitimate sender, here are some recommendations to follow when creating the content of your email campaigns:

  • Keep your subject line between 35 and 50 characters long. The longer your subject line, the more likely it will be flagged as spam by Internet Service Providers (ISPs) like Hotmail or Gmail. Having strong and impactful subject lines will also help grab your readers’ attention and generate better open rates. 

  • Do not use all-capitalized words in your subject line or body. It's a spammer's behavior that may make you look suspicious to ISPs. Also minimize the use of bold text, red font, exclamation points, question marks, and symbols like $ € £ @ in your email copy. 

  • To protect you from being mistaken for a spammer (or worse, a phisher), you need to avoid the words most frequently identified by spam filters as being suspicious, especially when used in the subject line of your marketing campaign. 

  • Avoid sending messages that have only a single large image or are only made of images, like spammers usually do. Make sure to have a good balance of approximatively 70% text and 30% images. 

  • Send content your email subscribers have signed up for. If you send non-relevant content to your email list, your subscribers may unsubscribe from your communications or mark you as a spammer. Also, the more people that open and click your newsletters, the better your sender reputation becomes. So, it's in your best interest to send them the content they want.


With one in every six messages sent worldwide failing to land in the inbox, crafting content should, first and foremost, be about maximizing it for deliverability.



Pro Tip

In addition to optimizing your content for deliverability, do not send attachments. Internet Service Providers (ISPs) become suspicious when they see bulk emails sent regularly with attachments, and they may mark you as a spammer.

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Want to know more about how you can apply these email growth tactics to your business? 

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