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Keeping Out of the Spam Folder

Nobody likes spam. Consumers don't want to receive spam, Internet Service Providers (ISPs) and email marketing platform don't want spam, and no business wants their emails to fit the definition of spam, putting them in the junk folder.

So, on behalf of Ideal Media, I’ve pulled together a few tips to help businesses who are sending legitimate commercial emails from mistakenly being routed by spam filters to the spam folder.

Internet Service Providers (ISPs) are waging war on spam- and their number one priority is to protect consumers against all spammers who may enter their mailboxes. Their greatest weapon includes spam filters that detect unsolicited, unwanted, and virus-infected emails and stop it from getting into email inboxes.

Spam is considered a such a real problem that organisations like the Spamhaus, who is responsible for blocking the vast majority of spam and malware sent out on the internet, works closely with Law Enforcement Cyber Crimes teams to assist investigations into spam gangs and spam operations.

But while working harder than ever to reduce inbox irrelevance, spam filters and ISPs give many "false positives", or legitimate commercial emails that are mistakenly being stopped by spam filters from reaching the consumer's inbox.

If you send enough email campaigns chances are you will run into spam filter issues. According to ReturnPath, about 21% of permission-based emails sent by legitimate email marketers went missing or went to spam.

That creates a significant challenge for any business that is trying to balance between growing their brand emailing list while protecting their reputation as a sender. So we've pulled together a list of tips to help you to be kosher and stay out of that pesky spam box!

Stay clear of sketchy purchased lists

Whether it be through a forum, a social media network or at an exhibition, we're all familiar with the kind of companies that tote purchasable lists for "bulk e-mail." But no matter the temptation, avoid these companies, as there are very few things that will make you suffer longer and more acutely than compromising on the quality of your mailing list.

One-time lists from these types of suppliers are little more than thinly-veiled time bombs, filled with dead emails and spam traps. Once the cheque clears, it is a high possibility that the list you purchased will severely damage your reputation as a sender by informing mailbox providers that you break the rules by sending unsolicited emails.

Instead of purchasing sketchy one-time lists, Ideal Media provides our consumer database, with over 100 variables, in its entirety to agencies that have the ability to securely hold and manage the data. Enabling you to offer your client a uniquely tailored approach where you can organically curate your mailing list over time while simultaneously improving customer experience. The Ideal Media database even helps you get more out of your current data, who doesn't like that?

Avoid spam trap emails

A build off my previous point- Spam Traps are email addresses that are flagged by ISPs as being no longer used by a human. They could be an old email address or something else. That means that if you are sending emails to these addresses, the ISP knows that there was no opt-in for the email received.

If you go with an email list provider who provides emails without opt-in, it is very likely that their lists are full of Spam Traps. And because many of the Spam Trap emails tend to look like active emails, there isn't any real way to distinguish them, which is why it is really important that you trust your partner and email provider at the risk of having to throw away all of the emails you've bought!

Avoid spam trigger words and phishing phrases

Yes, it is tempting to stand on the rooftop and shout to everyone how awesome and excited you are about your new product or sale, but many of the things that you might want to do to show your excitement could trigger the wrath of the spam filter.

Avoid overdoing things by including multiple exclamation marks for instance (eg. "New!!!"). Even naming prices could be a filter trigger.

Of course, there is no definitive list of "banned words" that you shouldn't use, but you should limit the use of potentially risky words dictated by common sense— such as “free,” “buy,” “promo,” etc.—reduces the likelihood of your emails landing in the spam folder. That also means that you should avoid things like hash busting or deceptive subject lines, such as starting the subject line with "Re:" or "Fwd:" which may suggest an ongoing conversation to the sender.

You should keep your subject lines and body clear, concise and easy to read. Emojis are also a great way to capture attention without triggering the filter. It also helps to use spam checkers like before sending your email out.

Include a plain text version of your email

One less commonly known truth is that HTML only emails are a cause for ending up in the spam filter.

So, although most email programs support HTML formatted emails, that doesn’t mean you should ignore the plain text version. A plain text email is what it sounds like: A simple email message that only includes text. No images, no graphics and no formatting. Even the links are written out. Simple enough right?

By including a text version of your email, you also cover yourself in case a recipient cannot view HTML emails. Considering the number of emails now being opened on mobile devices, including a text-only version is sure to remain a best practice for a long time.

Avoid large attachments and maintain a good text to image ratio

Don't go crazy with the email size (30 kb emails are fine).

If you are creating large emails or attaching large images or documents to your emails that are an issue. Sure, small .jpg, .gif, .png and .pdf attachments are fine to send if you are in good standing and include content in the email as well. But some attachments such as .exe, .zip, .swf, etc. should be avoided entirely and never sent to someone who isn't expected to receive them.

If you need to email a large attachment or an attachment type that is likely to be flagged as spam or trigger virus scanners, I recommend a service such as If the attachment contains sensitive data, you may consider using your company’s secure FTP server.

Stick to a limited number of verified, From emails

Where you are sending your email "From" matters almost as much as your content and subject lines. Mailbox providers pay close attention to your From field addresses.

  • Use clear From field names, like “newsletter@”, “support@”, "feedback@”, "hello@”

  • Avoid suspicious or obscure names, like “SuperSt4r@”, “noreply@”

  • Use as few field names as possible and avoid changing names

Get off the blocklists

Blocklists, (sometimes called blacklists) are lists of addresses and domains that have been identified as spammers and are blocked (by organisations like Spamhaus) from sending. If your email server ends up on a blocklist, it will become extremely difficult to reliably deliver email, especially to new people on your list.

There are a handful of free tools that will let you know where you stand, you can check to see if the IP Address you currently listed in the live Spamhaus IP blocklist email server is on a blocklist using free services including Spamhaus Blocklist Removal Center. If you find that you are on a blocklist, you will need to follow up with the site that has added you. It can be tedious and time-consuming, but removing yourself is crucial to ensuring your emails are received.

Finally, check your campaign formatting by using a spam checker before sending your emails

Conclusion! It's lots of steps, but worth it.

Yes, this seems like a lot of hard work and effort, but failing to do all of these activities could seriously undermine all of your efforts, get you on a blocklist and potentially turn off email subscribers. These steps can't be missed!


Would you like to work with us?

We have an audience of nearly 30 Million UK Households! We make use of everything from email address to home address, from favourite sports and hobbies to house size and car type. That means you can rest assured you’ll get exactly the list you need.

Michael Rennison has been in the Direct Marketing Industry for over 30 years and has specialised in the use of data for targeting campaigns and adding value to clients marketing services.

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