B2B Email Marketing: how not to end up in spam folder

The spam folder is a marketer’s biggest obstacle on his way to a successful campaign because this simple directory manages to make all efforts — market research, contact list building, copywriting — vanish into the wind. Considering that since the beginning of the pandemic the role of email as a marketing channel has considerably fortified, being classified as spam can really hurt B2B companies. Therefore, I’d like to elaborate on pithy pieces of advice to aid the cause.

SPF, DKIM and DMARC — do it fast and do it now

Briefly explained, all three relate to email authentication. SPF stands for ‘sender policy framework’ and refers to the records of servers and IPs associated with a particular domain from which emails can be sent, and can be theoretically compared to the return address written on a letter.

DKIM means ‘domain keys identified mail’ and symbolizes a trust signature, being created with the help of encryption algorithms and proving that you as the sender have the private keys authorizing you to send emails from that particular domain (you either own the domain or have permission to send emails on the owner’s behalf).

DMARC stands for ‘domain-based message authentication, reporting and conformance’ and is essentially a protocol based on both SPF and DKIM ensuring sent emails are protected by the two.

Email authentication can be tricky but the benefits it provides far outweigh the time spent for a few searches on how to set it up.

Use “curated” email list

Many go to great lengths to say that you should NEVER purchase email lists, and cold emailing is akin to spamming. Sending emails to prospects, retrieved from untrustworthy sources, might net you a few conversions. However, your email box will no longer be usable after the first batch.

When you do trust your data vendor, you should check with your email marketing software providers whether they allow addressing contacts from third party email lists.

Be solicitous about your contact data hygiene. According to a variety of sources, a normal data decay rate is about 20%-25% per year. Hence, in only one year of holding contact info, a quarter of them becomes no longer valid. The more invalid emails you’ll try to reach out to, the lower your deliverability rate and as a consequence the worse your sender reputation. If you decide to apply to a data provider, make sure you understand the quality of email addresses and the guarantees offered. For example, Global Database pledges for high accuracy rates, priding themselves in over 95% deliverability rates achieved by their clients.

Check whether you are blacklisted

IP-addresses that engage in spam-like behaviour and/or repeated offensive practices are flagged in a ‘blacklist’ database. Cybersecurity companies, mailbox providers and filters use the available information to issue actions on the offenders.

In case that your IP was flagged, you are in for a rough ride. To try to recover from such a low you will have to go through several steps, mainly providing proof of changing spam behaviour, to redeem your inbox’s reputation. You can see where this is going if you have been recorded by multiple blacklists.

Marketing platforms are not exempt from these unassailable guard dogs since sending spam from a shared pool of addresses will ruin both their reputation and yours.

When troubleshooting spam email, consider starting from the contents of the message then move to filters and work your way up to changing IP address or contacting customer support of the platform you use.

Court your subject line

The first thing a user sees while browsing through emails is the subject line. Therefore, it comes as no surprise that you must stand out and at the same time must not deceive your targets. If your subject line is embroidered in “sales” words, it will either reach the spam folder or be marked by users as such.

Do not, and I repeat, do not think of using “Re:” and “Fwd:” to trick your recipients into believing that you have been previously exchanging mails. The same rule applies to typing in all caps and stacking a row of emojis thinking that you are quirky and witty.

Unscrupulous usage of words

Have you recently received an email claiming “Double your income”, “You’re a winner”, “Free stuff”. Most likely you did not, because they are all sitting in the spam or have been deleted automatically.

All email content, from head to toe, is scanned for both security and pleasurable experience reasons. Combinations of words might get flagged and trigger the overall credibility score to go down.

Make sure you stray away from blacklisted words in your email body. There are quite a few lists and services that can check the quality of your drafts beforehand.

Provide, at all times, an unsubscribe link and your physical address

This one is more along the lines of mandatory practice than consideration. It is required by law and transgressors can be fined a hefty sum. B2B emails are not exempt, so it would be in your best interest to comply.

It is good when people unsubscribe. Why? They went through the trouble of doing so rather than marking your email as spam and ruining your reputation. Yes, some of your indicators may suffer, but it is worth it in the long run.


Formatting is to emails as cursive is to handwriting. Randomly spacing your lines of text, or just using a bizarre font might appear as a defective automation system.

Email providers have different proprietary guidelines, but have come to agree on these points:

  • Don’t use limited fonts and include a “back-up” in case the first one fails to load
  • Adopt a mobile version
  • Keep image-to-text ratio low. Do not embed text into images. Do not use a large image as the body of an email. Make sure to upload a lower resolution and use suitable compression, especially if you are adamant about branding. Alt text may prove appropriate.
  • Build a clean HTML template or use one from a reputable service
  • Do not add any attachments — it’s straight purgatory
  • Use a maximum of 1 in rare cases 2 links per mail and do not shorten them (e.g. bit.ly or any services like that). Using anchor text is fine.
  • Make sure to use both text-only and HTML versions.

All in all, you should remember to always stay up-to-date on changes in email policies, ISP behaviour and spam filter technology and keep your email lists accurate.

Entrepreneur. Founder CEO at Global Database. Hi — nice to meet you here. I’m passionate to write about B2B sales and marketing, providing useful insights.

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