How to improve email deliverability and get in their inbox

by | Tue 18 Aug, 20

Email marketing is an amazing marketing tool that offers unmatched ROI and precise, versatile targeting…

…If, of course, you manage to get in their inbox, in the first place. 

Unfortunately, at least 50% of email content (as of March 2020) is spam, and a whopping 20% of emails end up either getting blocked or sent to the spam folder.

Long gone are the days of ‘firing and forgetting’- marketers need to be proactive with maintaining their email deliverability, so they can reach their full audience, and maximize their ROI.

Today, we will look at the biggest tips and techniques to help you accomplish this.

Monitor your sending reputation

Your sending reputation is the hidden score that determines whether or not your emails get sent to the primary inbox, promotions inbox, or- goodness forbid- spam. If your reputation is poor enough, your emails will not even send- you get blocked.

You should keep track of this score regularly, to identify what actions are causing it to increase, or decrease.

ISPs track this, but do not always report it. Some good resources to monitor your reputation are,, and BarracudaCentral.

Be strategic with sending emails

Never send out any email to your whole list, at once. To get the best results from your email campaign, you want to slow down and be strategic, so that you can test your IP’s performance, catch deliverability errors, find potential display issues, and maybe do A/B testing.

Send first to a small batch of select subscribers- those with the absolute highest engagement. As they interact with your email, they send a message to your ISP that your content is trustworthy, and high-content.

Then, ramp up; every day, send to a gradually increasing number of subscribers, until you reach everyone you want. 

Send emails out at set, scheduled times to avoid creating sending spikes (bonus- experiment to see what time(s) of day give you the best engagement with your list!). 

And, now- here’s a very underappreciated email marketing tip…

Provide a preference centre for your subscribers, so that they may choose what type of email content they receive, and at what time, how frequently, etc. You will empower them to self-filter for content that they will be most likely to engage with- and, thereby, stay subscribed and continue to interact with your emails, further boosting your reputation.

Maintain a supremely clean list

When it comes to building, and maintaining, your email list… Quality always beats quantity. You must be considerate with adding new subscribers, and quick to purge low-quality email subscribers.

You should regularly remove inactive accounts. This includes accounts that have been inactive for 3+ months, or who have not interacted with any of your emails in 6+ months, or are from burner sites. When you send emails to these dead-end, useless recipients who never open, you continually signal to your ISP that you send content to readers who do not engage. This looks bad and hurts your sending reputation.

On the flip side, while building your list, you should take care to only add people who consciously want to join.

To accomplish this, use a dual opt-in, where subscribers must confirm their verification when they sign up- just to make extra sure they really want to be on your list.

Lastly, make it super easy to unsubscribe from your list in each email (yes, it sounds counterintuitive, but there is actually not much (if any) proof that ISP’s punish unsubscriptions at all). 

If someone is dissatisfied with your content for any reason, you seriously want to avoid getting marked as spam. Plus, if they’re planning to unsubscribe so casually, they are not likely to buy, anyway. Your reputation is more important than anyone potential customer.

Some companies give a quick, multiple-choice prompt asking for a reason for their unsubscription; you can gather data, identify patterns that cause unsubscription and fix the issue.

Do not EVER buy email lists

It’s an annoying business practice, and it reflects terribly on your company, and email marketing as a whole.

More importantly, it’s just plain bad for your bottom line. Sending out mass, unsolicited emails to strangers is a surefire way to rack up incredible numbers of spam reports. destroying your sender reputation.

Worse still- you may get ensnared in the dreaded claws of a spam trap, which are often slipped into these for-sale email lists, like a poison pill.

A spam trap is a fake email address used by ISPs to cut down on spammers. Any sender that sends an email to a ‘spam trap’ email address, will get instantly flagged and stuck in a ‘deny list’, where it’s near impossible to send any emails at all. This is the absolute fastest way of destroying your capacity for email marketing.

Deliver engaging, quality content

This sounds obvious enough, but it’s worth discussing in detail.

The more engaging and valuable your emails are to your reader, the better it is for you, and your deliverability. It will increase metrics like open rate, click-through rate, and reduce your bounce rate. Successful performances in these KPI’s are not only important to your bottom line; your ISP plays close attention to those KPI’s, and this has a big effect on your sender reputation- and therefore, your deliverability.

By keeping a highly engaged audience, you send a strong, unmistakable signal to your ISP that you are providing non-spammy content that your audience loves.

The flip side, here, is that you want to be extremely selective about the quality of your content- you want to be sure that you never risk offending or insulting those in your audience with content that’s offensive, glitchy, or irritating.

If you upset or anger a reader, they will likely mark your email as spam- perhaps simply out of spite- and thereby do serious damage to your sending reputation. 

Miscellaneous tips

Verify your email domain: ISPs strongly prefer you to send from an email address from a verified domain. Some savvy marketers take it a step further, and they register a dedicated subdomain for use exclusively in email.

Avoid spammy words: ISP’s automatically scan your copy- especially your subject line- for ‘spam’ words. If your copy gets qualified as ‘spammy’, your reputation and deliverability will take a big hit. Writing with non-spammy copy is not as simple as you may think. Obviously, things like “FREE!!!” or “RISK-FREE” or “CONGRATULATIONS!” are a big no-no, but many innocuous words also pop up red flags- including such common words as “lose”, “opportunity”, “call”, “here”, and “click” (and many, many more). is a great free resource that alerts you to spam triggers in your copy. Take extra care to keep your subject line free of spam words.

Ensure legal compliance: It’s important for you to stay compliant with the regulation on marketing in your country’s applicable marketing and data protection law. The GDPR, for the EU, is one of the most well-known, but virtually every country has their equivalent. ISP’s are quick to crack down on senders who get caught violating compliance laws.


Remember that everyone on your list (if you’ve played fair) is there for a reason; they want to receive your content. That’s why they signed up!

By taking care to maintain your sender reputation and deliverability, you empower yourself to consistently connect your brand with your audience, and make the most of your marketing. 

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