Maximize your email deliverability

Get the most out of your email marketing efforts

Chapter  1 :


Growing your email list can be a slog with endless marketing tasks like content creation, social media, and networking.

And whether it's a spam folder, unsubscribes, or people simply ignoring your offers, it's frustrating when your emails to that painstakingly cultivated list go unread.

Which leaves you asking, "Why?" Why is your engagement rate going down? Why are your emails going to spam? Why are more people unsubscribing?There isn't one straightforward answer, but there are a lot of factors at play and a lot of things you can do to increase the deliverability of your emails.

In this guide, you'll learn:

  • What a sender reputation is and how it impacts your deliverability

  • How spam complaints affect your emails even if you're not sending spam

  • The why and how to keep a clean list

  • Tools you can use to get better inbox placement

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Chapter  2 :

Your sender reputation

Hand with finger pointing at an envelope

Remember that guy from high school-the bully who made your life miserable? Chances are that if you see him pop up in your Facebook feed or you run into him at your reunion, those negative memories will be the first ones that pop into your mind, even 20 years later.

Email sender reputation works like your real life reputation: It stays with you.

Think of your email sender time-consuming your credit score--it's difficult and time-consuming to build, and very, very easy to destroy. A 2015 study by Return Path, a global data solutions provider, found that about 56 percent of email deliverability problems are attributed to a poor sender reputation. At its most basic, your sender reputation is the reputation that Internet Service Providers (ISPs) associate with your email domain, but in reality, it's far more than that.

3 factors that impact your sender reputation:

1. Your content

What you put in the body of your email impacts your reputation and your deliverability. This includes:

  • Spam-like content, headlines, or images

  • Your image-to-text ratio (industry standard is 80:20)

  • Your links. If you link to other domains that have low reputations, their reputation will reflect poorly on you think of it as guilt by association

2. Your server/email service provider (ESP)

Think of an email service provider (ESP) as the engine behind the marketing emails you send. An ESP is not Gmail, Yahoo, or Outlook; Gmail and Yahoo are web mail providers (which means emails are sent, received, and stored through an online browser) and Outlook is an email client (which is computer software that stores your emails on your computer, not online).

ESPs like Keap, Emma, or MailChimp also have reputations, and their reputation directly impacts your email deliverability. That's why knowing things like an ESP's deliverability rate (Keap has a rate of 99.5-plus percent) is important.

There are a lot of things ESPs do to keep their deliverability rates up. Just some of the ways we do this at Keap (and many ESPs will implement some similar steps) include by monitoring and vetting their customers' lists, authenticating emails, handling bounces, monitoring IP reputation, and having a human compliance and review team. You don't have to know what all of these things are, but it is important to know that ESPs have a lot of measures in place to maintain their deliverability, including ensuring their users follow list hygiene best practices. Otherwise their reputation-and your deliverability-go down.

3. Your sender domain

This is your domain-the part of your email address that starts with "@" and ends with ".com" (or .org, .edu, or .anything nowadays). The reputation of your sender domain follows you everywhere-no matter which ESP you use or whether you switch ESPs.

If you're falling down in any of these three areas, you're in danger of not making it to the inbox. We know, we know. You're not sending spam-at least not intentionally. But getting into the nitty-gritty on email deliverability means diving into the world of spam, and learning how you might be sending it without knowing it.

Remember, your domain's sender reputation includes everything that's ever been sent from that domain. What if one of your employees, operating under your domain, got a virus on his computer and the virus sent out tons of emails from your domain? Stuff like that can get you blacklisted. That's a nightmare scenario, but it illustrates that having a bad sender domain reputation doesn't mean you're a bad person, it just means there are improvements you can make.

Chapter  4 :

Maximize deliverability through list hygiene

Admittedly, on the list of exciting things about running your business, "list hygiene" is probably not up there. But it should be! Practicing good list hygiene can have an enormous positive impact on your email list-and by extension, you're bottom line.

Illustration of envelope and letter with a heart on it

Quality over quantity

First, we need to get in the mindset of valuing the quality of an email list-and not the quantity of emails. You've spent a lot of time and energy growing your list, and you've done a great job.

But in order for that list to be effective, it has to be made up of recipients who want your quality emails and who engage with them.

Remember, sending emails to those who don't want them is about as effective as trying to sell Kanye West on the idea of a vow of poverty.

Here are some ways to keep a clean list to increase the deliverability of your emails as you grow your list.

Remove emails from your list

It's tough to remove email addresses off the list you fought to grow, but cleaning up your list will increase your deliverability because you'll end up with fewer unsubscribes or unopens, which translates to higher engagement and better inbox placement and deliverability.

Here are the types of recipients you should remove from your list:

  • Unsubscribers
  • Those who mark as spam
  • Hard bounces (invalid email addresses that return your email)
  • Stale subscribers (recipients you haven't emailed or who haven't engaged with or opened your emails in four months or more)

Keap will automatically removes these addresses from your marketable list when these actions happen in our ecosystem.

A note on stale subscribers

Stale subscribers are perhaps the most difficult to conceive of removing from your list. After all, they opted-in at one point, and they didn't unsubscribe, right?

It's important to understand that an opt-in is not an eternal agreement. You have to get ongoing permission to send emails.

This comes in the form of useful, frequent communications. Stale subscribers can be high risk because they're the most likely to forget why you interacted in the first place and thus are the most likely to mark your emails as spam. Making a practice of sending emails to stale subscribers can really cause your sender reputation and deliverability to take a hit.

You don't have to give up your stale subscribers right away- instead, put them on their own list and send them another email asking them to opt-in again. In the worst-case scenario they won't reply or will unsubscribe. This is actually a good thing as it helps you make sure you keep a list of subscribers who want to engage with you and your emails. Remember, a big but stale list does you no good. It's all about engagement; play the percentages.

In the best-case scenario they re-opt-in to your list and become engaged subscribers, which means you've just added to your subscriber list in a valuable way.

Illustration of email and laptop in the clouds

What to do if you switch ESPs

When people switch ESPs, they tend to expect that more people will get their emails, especially since they hear a lot about an ESP's great deliverability rates and good sending reputation. People expect that opt-in rates will go up while spam complaints and opt-outs will go down.

Having read all that goes into sender reputation and list hygiene, at this point you shouldn't be surprised to learn that this is not the case. In fact, the opposite often happens. But don't panic! There's a good reason, and it's very avoidable.

Remember, your domain's sender reputation remains with you. But when you go through a new ESP, unengaged recipients might suddenly see an email from you in their inbox when your emails had previously been going to spam. After months of thinking they haven't heard from you, they'll see this email from a new ESP and think, "Why am I back on this list?" Then they get frustrated and either opt-out or report you as spam.

If you have a squeaky clean list, you probably won't have this problem. But if your list needs a bit of cleaning, the spike in spam reports and opt-outs can seem shocking. So before you switch to a new ESP, clean up your list and segment it into engaged users and unengaged users.

Before you switch ESPs, send an email to your unengaged (but not opted-out) users and offer them an incentive to reengage or re-opt-in. Then, if they opt-in, move them to your engaged list (which should be your primary list). If they don't, consider them dormant and don't send them regular emails.

Email servers in the clouds

You should also send an email to your engaged users, again, before you switch ESPs, that let's them know you're switching email providers and that offers an incentive to send them something for free once the switch happens. Then send the offer from your new ESP. You might also want to ask them to make sure to move you from the promotions folder to the primary inbox, or to add your address to their contacts.

By giving engaged recipients the heads up and an incentive, you create anticipation so that when they receive your first email from your new ESP, they'll open it and your engagement rate will increase.

This way, when you import your list to your new ESP, you'll be assured that your regular, engaged recipients are the one receiving emails from you, and you can mitigate initial opt-out or spam spikes.

Chapter  5 :

Maintaining a great email relationship

As in real life, maintaining a positive relationship with your email subscribers requires frequent but not pestering communication. When you're texting with a paramour, both radio silence and continuous messages are not good, you have to hit that sweet spot. It's the same principle when emailing your list.

First, make sure that when you obtain opt-ins, you state what the frequency of your communications will be so that you set expectations from the start. Then, maintain that frequency.

If you lapse in your communications for a while, then they suddenly start receiving more frequent emails, people might feel spammed.That said, don't scale so far back on your communication that your list goes cold. We recommend that you contact your list no less than quarterly.

You also need to ensure that the content in your emails is relevant and consumable, and part of that is not automatically opting people in to newsletters or other emails. Remember, permission is only explicit when it's voluntary.

Email deliverability isn't always simple, but it is pretty straightforward: Make sure that when you send emails, you're sending them to people who want them when they want them and that they contain the content recipients want. Keeping your goals focused on your recipients instead of just your list- growth goals will help you reap repeated long-term rewards.

Chapter  6 :

About the author

Author, Ellis Friedman

Ellis Friedman

Ellis has spent a lot of her adult life chest-deep in small business adventures, especially the year she spent opening the Beijing branch of a Shanghai-based air purifier and lifestyle business. Most of her experience stems from her diverse media background in film, magazine publishing, blogging, and photography, but she's also a published author. Ellis has an idiosyncratic fondness for grammar, style, and sarcasm, and fills most of her time away from the keyboard tasting scotch whisky, traveling abroad, and hiking.

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