Ultimate Guide to Email Deliverability


Email marketing is the most cost-effective way to reach your supporters in a digital world. Acquiring email subscribers and maintaining a good reputation with email service providers can be tricky. The last thing you want as an email marketer is to run into email deliverability issues which can impact – or even shut down – your email program.

It may appear that nonprofits and charities don’t do ‘marketing,’ but every bit of outreach from web to social media to email to advertising is indeed marketing. Email marketing is one of your strongest channels. Supporters have opt-ed into direct communication with you by email, and you can customize messages that resonate with them. It’s also incredibly affordable, can provide deep integration with other tools you use for fundraising, and typically has a good return on investment (ROI).

Email marketing builds relationships with your supporters. You can’t just hit send to everyone on your list anymore, though. There are rules.

Email deliverability is a significant problem that marketers face. In this guide, we’ll go over the basics of email deliverability, issues to watch and how to rectify the situation if needed.

What is email deliverability?

Email deliverability isn’t a new term – it’s something marketers considered for many years. Recently, however, you might have noticed that the term is mentioned more often. That’s because it’s affecting more and more organizations as the rules change and become more strict.

Email deliverability essentially describes the success rate of your emails reaching the inbox of a subscriber. Higher email deliverability means more people will be able to see the emails you send them. Good email deliverability means more supporters see your messages and take action or donate.

Many use email deliverability as a marker. Some factors tell you how likely your emails are to reach the inbox of a subscriber. When it reaches their primary inbox, the chance that the email will be opened, read and acted upon becomes significantly greater. Most people don’t even bother to look in subfolders, let alone spam or junk.

Many factors affect your email deliverability that can have long-term impacts on your email marketing strategies too.

Marketers have found that certain email service providers (ESP, but not the telepathic kind) are tightening restrictions on the number of bulk emails allowed to reach subscribers on their network. The primary idea behind these rules is to ensure there is a limitation placed on spam and unwanted emails reaching the user’s inbox.

Google and Yahoo (owned by Microsoft) are among the top email service providers of interest when looking at email deliverability. When reviewing your email list, you’ll likely notice that Gmail has a strong (if not majority) presence. They have stringent rules about deliverability and also provide many tools to help marketers manage it.

Why does email deliverability matter?

By the end of 2019, around 3.9 billion people worldwide had an active email address.

In the same year, an estimated 293.6 billion emails were distributed (sent or received) every day.

By 2023, the number of active email addresses is estimated to grow to at least 4.3 billion. This means within the next three years, roughly half of the global population will have one or more email addresses. By this time, more than 347 billion emails will be delivered daily.

Things get interesting when looking at the return on investment related to email marketing. The average marketer can make up to $42 in profit for every $1 they spend on an email marketing campaign. That’s an impressive ROI.

The problem is, if the emails you send aren’t delivered to supporter inboxes, these figures hold little value for your organization or marketing efforts.

Email deliverability tells you how many of your emails are likely to land in your subscribers’ inboxes. If your email isn’t being received, there’s a problem – low (or poor) email deliverability.

High email deliverability means you are able to uphold trust among ESPs that host email accounts for your subscribers. It also means your campaigns will reach more inboxes.

Email deliverability and nonprofit organizations

Nonprofits operate differently from businesses in the private sector in some ways, but ultimately, they run marketing programs just like corporations (perhaps just on different budgets). Nonprofit marketing campaigns are designed to bring in supporters who will take action and donate. In 2019, Americans donated over $449 billion. Being seen by your email subscribers is essential to your bottom line.

There are many strategies that nonprofit organizations use to drive higher donations to their cause – and most depend on email in some way. The rules for email deliverability are the same regardless of the sender. The ESPs don’t care if your a multi-national corporation or a small nonprofit running state-wide advocacy.

When there is poor email deliverability in a nonprofit organization, you may encounter:

  • Your emails are not reaching subscribers, which essentially means you’re wasting staff time building and sending email
  • Inbound revenue and subscriber retention will decrease, as people don’t see your email
  • The reputation of your email marketing campaign’s IP address may at risk
  • Who are you? When you’re not reaching out to supporters… they might forget you – and later unsubscribe or report you as spam
  • In most cases, your charity doesn’t run a store, and one of your primary revenue streams is impacted

What affects email deliverability?

Now that we’ve reviewed what email deliverability is and why the term is important, we need to look at what can affect it. There are several factors to consider when estimating email deliverability.

Email content

Let’s start with an obvious one – the actual content of your email. It’s tempting to focus on creating an attractive email design and content that will help to improve the click-through rates. Unfortunately, that’s not the only thing that you need to take into consideration.

Subscribers expect personalized content – know their name and provide something relevant to their interests. And the ESPs are watching.

Make sure you address the subscriber directly in the email – make it personal. This is an important way to help improve open rates and increase the chances of getting the email into subscriber inboxes.

Need some tips on good personalization? We’ve got you covered. Read our post, “10 Tips to Help You Get Personal with Donors”.

Avoid impersonal email content that comes across as advertising. Too many images combined with little text may interfere with your email deliverability.

Focus on the subject line of the email – this is another area that ESPs look at when filtering emails for spam and junk content. Make the subject personal without sounding like promotional content. If it gets picked up as spam, you may be blocked. Or worse, your own supporters may flag you as spam.

Reputation of the sender IP

When it comes to email deliverability, sender reputation is another vital factor that affects the chances of getting your email into the subscriber’s inbox. This may or may not be related to you specifically, but rather the server you use to send your email.

There is an IP address associated with the server used to submit emails to your subscribers. This is what you need to look at when considering sender reputation. If that IP address gets blacklisted that could mean trouble. In this scenario, having a good relationship with your eCRM company is invaluable. They are likely already tracking back-end performance like this and can help troubleshoot and resolve issues.

There are a few online tools that you can use to help with this particular step. MX Toolbox lets you look up IP addresses and their related information. You can also check if the IP used to send and deliver your email campaigns has been blacklisted on any servers. Simply visit the MX Toolbox Blacklists page – enter the domain you send from or the server IP.

You will be presented with a full list of ISPs and blacklist databases that are used by email providers like Google and Microsoft to check if an IP is associated with a negative reputation. Make sure all of the “status” results are marked as “OK.”

The gold standard – and its free to use – is Google’s Postmaster Tools. You can track spam complaints, IP reputation and your own domain reputation. Watch this video by 250ok to learn more about Google Postmaster and how it can help you track these tricky issues.

Subscriber behavior

Another thing that can have an effect on your email deliverability is subscriber behavior. ESPs have implemented technologies that monitor how people behave and react to emails you send. Do supporters open your emails, trash them or do they actually read the content and click links? This tells the ESP how reputable you are and if your subscribers engage with your email.

Email list quality

The “health” of your email subscriber list affects email deliverability. ESPs tend to look at bounce rates, spam traps, and other related issues. If you have a lot of dead subscribers on your list, it means there will be a higher bounce rate.

Spam traps are fake emails that are used by ISPs to identify spam. These end up on your list through bulk acquisition campaigns or sometimes by subscribers sharing an old unused email. If there are spam trap emails on your list, it could get your IP address blacklisted quickly.

Fixing poor email deliverability

Even if you’re following best practices (although the chances are much smaller) you could encounter an email deliverability problem. The good news is that you can implement steps to turn things around.

Diagnosis of the problem

The first step is to diagnose the problem. You need to know why your deliverability is low in order to take any appropriate actions.

The issue could be relatively simple or very complex. If you don’t know where to start, you could invest considerable resources fixing what may have been a simple change. Start with your Google Postmaster Tools and see if you can track down information there. Reach out to your eCRM provider to see if they can offer insight. Evaluate your deliveries and see who’s missing – Gmail, Yahoo, Hotmail?

Be your own detective and track down the source of the problem as best you can. Then you can create a plan to solve it.

Why? Having an idea of the source of the problem gives you a place to start when building a plan to fix it.

Clean up your current email list

Start with a strategy that helps you clean the current email list you have. This will give you an opportunity to remove bad and toxic email addresses from your list. These are essentially the email addresses that cause your server IP to be blacklisted.

There are a few useful tools that can be utilized to clean up your list. Neverbounce is considered an effective option and offers a nonprofit discount but there are others out there. It will filter through your email list and remove any email addresses that are duplicated, as well as those that are bouncing or considered a “bad email address.”

Why? This will prevent you continuing to send email to spam traps or bad emails as you’re trying to fix things. That would only perpetuate your problems.

Authenticate your domain

This step is a bit more complicated but basically, you need to tell the ISPs that you’re legit. While you can do just a few of these – all will get you to a resolution faster and certainly won’t hurt for a good future sender reputation.

  • Authenticate your domain with Google and follow their best practices for email deliverability (which they are very transparent about)
  • Ensure your email messages are signed with DKIM and need to use a key size of 1024 bits or longer
  • Publish an SPF record for your domain
  • Publish a DMARC record for your domain
  • Google also recommends you send your emails from a single IP address and do not frequently change the server IP used for sending email

Again, Google’s best practices for email deliverability covers this and much more and you can find it here.

Why? If the ISP’s know you’re a real organization sending real email and following the rules and best practices it puts you on the right path to a good sender reputation.

Develop a segmentation plan

Setting up a segmentation plan is another useful strategy that you can rely on. To dig you out of the hole of poor email deliverability, consider sending to your most engaged supporters first as they’ll click and respond to your messages. Then, send to less engaged… and less engaged. You can target supporters based on various levels of engagement in Engaging Networks using our Engagement Scoring tools. That’s a mouthful.

It’s good to exclude unengaged supporters altogether, especially as you’re fixing email deliverability. The last thing you want at this time is to be flagged as spam or have a boost in unsubscribes.

Why? Thoughtfully approaching who you email at this time is crucial and can make or break your recovery. Focus on quality and engagement.

Consider a new IP

If you find that the IP used to send your email campaigns is blacklisted, getting it removed from the blacklist can take some time and effort from your side.

For some marketers, obtaining a new IP address may be the ideal solution. You’ll need to contact your eCRM provider to discuss options. They can advise on the procedure for obtaining a new IP address on your account if it’s an option.

Why? If your IP has been blacklisted, weigh whether you have resources and time to recover that. It may be easier to get a new one even if there is a cost involved.

Maintaining good email deliverability

If you already have an email campaign with a satisfactory email deliverability rate, you will want to maintain this achievement. With this in mind, you need to take appropriate steps to keep that list healthy and ensure your emails are effectively delivered to subscriber inboxes. Here’s a simple checklist for monitoring:

  • List hygiene: Develop a list hygiene checklist for your organization that includes
    • Annual (or more frequent) list scrubbing using a service that will remove bad emails
    • A plan for targeting only engaged supporters which will reduce bounces
    • Periodically purge your email file of unengaged suporter emails
    • Consider using a service to validate emails in realtime (there are several out there but many of our clients use Neverbounce) – this keeps your list clean from the moment of sign-up
  • Sender validation: If you haven’t already, take the time to add DKIM, SPF and DMARC to your email
  • Monitor sender reputation: Set a plan to check Google Postmaster regularly and keep an eye on your reputation
  • Focus on best practices: Give thought to email quality and follow the rules
    • Avoid spammy subject lines
    • Relevant content with a good balance between images and copy
    • Personalize copy
    • Never send to unsubscribe
    • Never send to anyone who has not opted into your list
    • Welcome new subscribers and keep in touch so they don’t forget they signed up with you in the first place
    • Make it easy to unsubscribe – you can also offer subscribers options to set the rules in an email preference center

Wondering how to target supporters based on engagement? Engaging Networks offers built-in engagement scoring that can be used to segment email subscribers based on level of activity.

That’s a lot of information. We have the benefit of having an email deliverability expert, Gwynne Dixon, on staff at Engaging Networks. Take a breather to watch a short video from Gwynne Dixon on best practices or from our partner CCAH.

Wrapping it up

You’ve taken the time to educate yourself on email deliverability, bravo. Now, evaluate your email program and determine if you’re following best practices. If not, take the steps now to set up monitoring and make adjustments to your strategy as needed to avoid poor email deliverability.

If you find yourself in the scary situation of a bad sender reputation and poor email deliverability – take a deep breath and know you can recover from this. Follow the steps outlined in this guide and create a plan to move things in the right direction. If you feel overwhelmed, many of our accredited partners have experience helping clients repair reputation and return to inboxes. You can find a list of partners here who can help you.

If you have a bit of time, watch this presentation from our 2018 Engaging Networks Community Conference on how our accredited partners at Beaconfire RED turned Ocean Conservancy’s email deliverability issues around in time for year-end fundraising.

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