A few weeks ago, I exposed a snippet of my spam folder at Cloudera.


SDRs and marketers were blown away. “Wow Sara. That will make me look into my mailbox’s Spam folder.”

I, on the other hand, was shocked by the response the post received. Many folks were agreeing with the message, but many also seemed shocked at what I was exposing. Shocked that emails that looked like theirs were ending up in my spam folder, never to be seen by me.

But, as marketing and sales professionals, we face a lot of challenges when it comes to getting our message to a place where our recipients can even be aware that it was sent. A lot of us just don’t realize it.

We see the “delivery rate” stats in our marketing and sales platforms, and assume that our emails landed safely in inboxes, right in front of our prospects and customers.

But a lot of the time, they didn’t. It’s okay if this is news to you — I’m about to arm you with information that will help you land in the right spot. 

Email Service Providers

This is the crux of the struggle of email marketing. Email service providers (ESPs) scan email headers and content to decide if your email deserves to hit my visible inbox, or if it deserves to be sent to my spam folder or quarantined. They have custom algorithms set up to move what they consider to be global “junk mail” out of your inbox.

But they do this in secret. ESPs are notorious for not making any information about their filters public; after all, this would help likely spammers infiltrate your inbox. It would be like a building security officer coming up to you and saying “I know I’m protecting this building, but if you go around the corner, you can walk right in.”

So how do we combat this unknown entity? Well, based on tests and recommendations from the ESPs, here’s what we’ve been able to glean (and these are the rules that I personally swear by):

• Don’t use red text.

• Don’t use a lot of underlines, !s, or ALL-CAPS WORDS.

• Avoid using monetary values or scammy phrases like “FREE!” or “ACT NOW!” (many ESPs do have classifications of types of inboxes — if you’re in financial services, you’re less likely to be flagged for monetary/financial terms. However, you must still be careful.). Here is a great resource of spammy terms to avoid using, as well as corroboration of other rules mentioned here.

• Don’t say “Dear,” — this is a common spam trap.

• Don’t use all-image emails, or image-heavy emails. ESPs prefer text emails.

• Be sure that your html is written well (pro tip: hire a developer to create a few malleable templates for you).

• If you’re looking to use a new IP address, warm up your email sending reputation following a plan like this. Do NOT send your first email to 10,000+ contacts.

• Make sure your SPF and DKIM are set up correctly. Don’t know what those terms are? Here’s a guide. Here is a great email header tester, as well.

• Do not send emails to too many recipients within the same hour. This depends upon your database — I’ll get into that shortly.

• Analyze and re-engage or purge your database of inactive records periodically. This one is a tough one for folks to really grasp, as they cannot grab a direct statistic to show the damage inactive records do to their email deliverability. Instead of going on a rant about this, I’m going to let CampaignMonitor sum up the crux of the issue:

“In email deliverability terms, low open rates are a clear signal to ISPs that your recipients are not engaged with you, your brand or your content. That lack of engagement is a factor in the delivery of future emails and can even lead to your campaigns being blocked. Think of it as a snowball threatening to become an avalanche – your low open rates mean that ISPs block your future emails, which leads to even lower open rates which in turn leads to a further lack of engagement.

Considering taking action with a list that you’ve nurtured and grown over a long period of time may be difficult, but what’s worse is this – you could be damaging your sending reputation by continuing to send to people who have never opened your emails and you are paying for the privilege.” 

My addition to this statement is that many folks switch jobs more frequently, and their former companies seem to typically take up to 1 year to actually make their old email address undeliverable. However, not *all* inactive subscribers are trash: Litmus has a great article outlining some strategy ideas for different types of inactive groups.

But that isn’t all, folks. Let’s dive into other fragile areas for email deliverability.

Email Servers

Many companies share server services, so if your email is not well-received by recipients at one company, you could be shooting your foot re: deliverability to another similar company, in the same industry. Your email bouncing at Boeing could mean you have little chance to make it into the inboxes at Lockheed Martin.

This varies by audience. I once had a financial services audience max out at 30,000 emails per send, per hour, whereas in SaaS I’ve seen much larger volumes successfully be delivered. Make sure you watch your email statistics and learn how your audience is configured. 

Financial Services

Many of us market to financial services companies. If you are trying to send emails to a company like JP Morgan, you’ll likely need to reach out and have them whitelist you first. More on whitelisting here. Why?

Because these companies get so much spam email and phishing attempts that their email filters are flipped — instead of allowing the majority of emails to hit their inbox and sending a specific few to quarantine, you must be on a list of approved senders to deliver emails to these companies.


The word of true terror in the email marketing world — blacklist.

A blacklist is a list of spammers that you’re thrown on when you haven’t been following the best practices outlined above. Being on one of these lists often means that you will have a huge hard bounce rate moving forward, so it’s important that you use this tool to identify if you are on any major blacklists and work to get off any blacklists that your organization is on.

However, the mainstream blacklists aren’t the only ones out there — each IT group and/or server can create their own blacklists, so be sure to monitor the hard bounce messages you get in your marketing automation/email marketing platform for anything that needs attention.

If this sounds like a bunch of hoopla to you, SendGrid has a fantastic blacklist 101 article here.

At the end of the day, the best we all can do is practice email marketing best practices, offer our subscribers compelling and relevant content, make sure the tech is set up correctly, and hope for the best. The cards are stacked against us as marketers, which is why we have to get as precise with our messaging as possible. No more spray n’ pray! Now, it’s more like “be purposeful and measure success.” 😄

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Sara McNamara is a Senior Marketing Operations Manager and top-tier Salesforce/Pardot senior consultant that has been recognized as a “Top B2B Marketer to Watch” by Salesforce Pardot, a “Unicorn” by Marketo, a “Trailblazer in B2B Marketing” by Salesforce Trailhead, an “Ops Pro Shaping The Future of B2B Marketing” by Drift.com, and a “B2B Marketing Automation All-Star” by ChiefMarketer.com. Sara has a special place in her heart for marketing operations, reality TV, Kanye West, huskies, and people who don’t call her about something that could have been a text/don’t request a meeting about something that could have been an email.

Sara is honored to be the very first B2B marketing Trailblazer to be recognized and featured by Salesforce Trailhead, as well as featured in the first Trailblazers in B2B Marketing | Powered by Pardot magazine and featured at Salesforce Tour events around the world. She is also a Marketo Certified Expert and cosigned by Jill Rowley, the greatest sales professional of all time. 🐐 She has a hell of a lot to say and you can catch her thoughts on Twitter at @ifeellikemacmac, on LinkedIn, and at various marketing events in the United States. You can also catch peeks of Sara featured at Salesforce Tour events worldwide. 🌎

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