March 28, 2012
How To

B2B Email Deliverability: 11% of B2B email is classified as spam, these 6 tactics will help

SUMMARY: Deliverability is a complex topic that challenges every marketer using email. However, it is an even greater challenge for B2B marketers.

B2B marketers must meet unique deliverability rule sets for each individual domain in databases filled with hundreds or more. Whereas B2C marketers likely have a database full of freemail accounts, and can resolve an issue with that provider and settle a huge portion of the list with a single effort.

Read on for six tactics from two email deliverability experts. They cover tactics on reputation, testing, domain distribution reports, mediation and more.
by David Kirkpatrick, Reporter

Email deliverability poses some unique challenges for B2B marketers that their consumer marketing peers don’t typically have to deal with.

To address this issue, MarketingSherpa reached out to two deliverability experts: Tom Sather, Senior Director of Email Research, Return Path, and Stephanie Miller, VP of Email and Digital Services, Aprimo.

Sather said the main issue with B2B email deliverability is there are more points of failure. Miller explained that a consumer marketer might be sending a very high volume of email, but maybe 40% of that total is going to a freemail provider, such as Gmail.

Both stated that while the B2B marketer might send a lower volume of email, the number of different domain and email systems involved in a B2B campaign is typically much, much higher than what the B2C marketer has to deal with. This is because each email is likely going to a corporate account.

Deliverability isn’t a major impediment for most B2B marketers -- Return Path’s "The Global Email Deliverability Benchmark Report, 2H 2011," found 11% of B2B email is classified as spam. But it’s good practice to understand how to fight the problem when it does arrive, or even better, to avoid the problem to begin with.

How to uncover an email deliverability problem

"What is the first thing we do when a campaign doesn’t perform well?" asked Miller. "We blame the creative."

Instead of wondering if the offer wasn’t strong enough, or if prospects don’t like the color blue, Miller said to look at response rates. If there is a sudden dip, or even a decline, that might be an indicator that the email send is having an inbox placement problem.

She said to run a domain report (see Tactic #3) and find out if you have no opens or clicks from a particular domain. If that is the case, you are possibly being blocked.

Sather added two tips for email deliverability issues:
  • Regularly check bounce files

  • Invest in deliverability monitoring tools with insight into B2B filters -- your ESP should be the first stop for these tools

Tactic #1. Understand the path your email takes

As Sather put it, "When you look at the enterprise and mailing to corporations, (the email) goes through probably three major ‘buckets.’"
  • First is the initial gateway filter that checks to see if the IP address is blocked and if the system should even be accepting the mail into the enterprise.

  • Second are hosted filters that evaluate the message for its content and reputation.

  • Third are top filters, such as those built into Outlook.

If possible, understand the rules built into this path, Miller added. This is where B2C marketers have a leg up on B2B marketers. When almost your entire database is made up of three freemail domains, learning and adhering to deliverability rules is much easier than when dealing with many, many different domains and systems.

She said, "When you have hundreds, or thousands, of different corporate domains that you’re sending to, and each one of them has their own set of rules, that magnifies the challenge of getting to know exactly how each individual domain is going to accept mail."


Another concern Miller pointed out is throttling. This is the number of emails sent over a period of time, such as rate-per-second.

B2B marketers have to get an infrastructure in place that will manage different throttling rates for different corporate domains.

She said the throttling rate might be set very high for freemail like Yahoo!, while it might need to be much lower for a corporate email server. The tradeoff is a high throttling rate gets the message out more quickly to more addresses, but deliverability suffers if that send exceeds corporate servers’ thresholds.

Personal filters

What might could be considered a fourth "bucket" to add to Sather’s list of filters are the personal filters and email rules that individual users apply within the email application they use to read the messages.

"Individual employees might have certain filters on their desktop," explained Miller. Those employees could have their own rule set in place for email delivery to their own inbox -- for example, a rule that blocks certain words or phrases in subject lines.

When looking at the path taken by the sent email, it becomes obvious there are many places for delivery failure.

Tactic #2. Measure your reputation

"Everybody faces inbox placement and acceptance on sender reputation," Miller said. "And sender reputation, in all cases, is made up of the same kind of factors."

These factors include:
  • Complaints

  • Cleanliness of data

  • Number of bounces or unknown users

  • Content

  • Frequency

  • Relevancy

  • Infrastructure the mail is sent from

  • Authentication scheme

Sather added that many enterprise system filters rely on content, but the trend is moving toward utilizing reputation-based systems to determine if mail is spam or not spam.

He added there are a number of online places to look up your reputation based on your IP address. (See "useful links" at the end of the article for some suggestions.)

If you are having deliverability problems, Sather recommends you begin investigating why by looking at your IP address and learning what your reputation is.

Tactic #3. Create a domain distribution report

A domain distribution report uncovers the top 50 to 100 domains in the email database. The criteria for the top domains could be size -- the number of people within each individual domain -- or value, because as Miller put it, "some customer accounts are more important than others."

The main point is to choose criteria that make the most sense for your business when creating the report.

Once the report is in hand, find out the delivery rate and the bounce rate to make certain email to those top domains are being accepted.

From there, dig in even further, because the mail might be accepted by the server but still not make it to the inbox. The metrics to track here are open rate and clickthroughs.

Miller said to compare the open rate and CTR for your entire list of top domains to find an average figure for your email sends.

For any that are much lower than normal, there might be deliverability issues.

When that is the case, she offered a few ideas:
  • Lower the throttling rate

  • Try to learn the individual reputation rules for those domains

  • Actually reach out to the system administrators to uncover and hopefully resolve the issue (see more on this in Tactic #6)

Tactic #4. Test the content of the email

If deliverability is already an issue, Sather said to begin testing the content of the mail, including subject lines, keywords in the body and URLs within the content to determine if any of those elements are getting the email flagged, blocked or filtered.

He suggested beginning with URLs because this element often has a reputation attached to it. A third-party link inside an email might get flagged, or use of a URL shortener (like bitly) could get the mail automatically blocked as spam because these tools are often used by phishers and spammers.

To do this, Sather said just send an email with nothing but the URL to your testing platform.
Once the URL testing is complete, he stated to move on to keywords, subject lines and then the actual text of the email copy.

To test email copy, Sather said to break the mail into individual paragraphs and test each individually.

He also mentioned using third-party tools where the email is sent to an address that runs all the content through a battery of email filters to flag any offending keywords. (See "useful links" at the end of the article for some suggestions.)

One final area of content deliverability issue is for the marketer who is sending email in one large image file to bypass content filters, some of those filters also look for overly large images and automatically block those email as well.

Tactic #5. Shared versus dedicated IP

A dedicated IP is one company sending email from one IP address. A shared IP is just as it sounds -- multiple companies using the IP, of most likely a service or vendor, to send email.
Why does this matter?

By using a dedicated IP pool, if there is one bad apple in the bunch, the reputation of every company sharing that IP suffers. To combat this, Miller said to stay in close contact with your service provider and find out who else is sharing the pool, and also keep track of your reputation.

"I think (using a shared IP) requires a level of vigilance on the part of the marketer," she said. "And, you should expect that your provider is also being vigilant on your behalf."

With a dedicated IP, the good news is you are in command of your reputation. If it suffers, it won’t be because another company using the address suddenly became a spammer.

The problem is, to maintain a high reputation, there has to be certain volume of mail coming from the IP address at a regular cadence. Miller said if your list is small, or if you only mail once a month, it will be difficult to keep up a high reputation. The result will be essentially having no reputation at all, which is just as hard on deliverability as a bad reputation.

Tactic #6. When all else fails, try a 'hands on' approach

There are times when reputation, content or other usual suspects don’t seem to be the cause of a deliverability problem. When this happens, Sather stated, "It is time to try and mediate with those filters."

He said companies specializing in email spam and Web filters, like Brightmail and Barracuda, have places where you can try to mediate or resolve an issue with an IP address.

To accomplish this, he said to begin on the website and enter your IP address with a request for removal from being blocked. He said from there the service will probably be in contact by email to begin the mediation process.

Useful links related to this article

CREATIVE SAMPLE: B2B email deliverability from the Return Path benchmark report


Return Path

Marketing Research Chart: Email deliverability metrics improving ... slightly

Webinar Replay: Top Email Tactics to Improve Relevancy & Deliverability

Webinar Replay -- Improve Email Deliverability: Tactics for Handling Complaints and Boosting Reputation

Email Deliverability: 6 tactics achieve near-perfect delivery rate for local deals site

Check Your Email Reputation to Improve Deliverability with Easy, No-Cost Tools

Email Deliverability: Global stats show North America leads — but we have work to do

Reader Mail: Understanding differences in clickthrough rates and open rates

Online and third-party tools:






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