The 5 Mistakes That Will Land Your Email in the Spam Folder Email providers and readers are raising the standards for what content makes it into the inbox and what lands in the junk pile.

By Aleksandr Peterson

Opinions expressed by Entrepreneur contributors are their own.

As marketing automation gains popularity many companies are expanding their use of email campaigns. Spammers, unfortunately, are also expanding their use of spam. In 2013, spam comprised an estimated 84 percent of all email traffic.

As a result, email providers and readers have raised the standards for what content makes it into the inbox and stays there. Even if you aren't trying to send spam (which we'll assume you aren't), many of your targeted messages could be filtered out of inboxes before prospects get a first impression. In addition to choosing the best marketing automation software for managing campaigns and tracking engagement, businesses need to identify the points of liability that cause well-intended messages to be flagged.

Related: 6 Email Personalization Techniques That Go Beyond a Name

How it happens

There are two main entities in charge of identifying "spammy" emails. The first is the internet service provider (ISP) that hosts a recipient's mail server. Google, Yahoo, and AOL are common examples of email ISPs. An ISP filter can flag an email if the origin domain or IP address is deemed untrustworthy, or if the email itself has a high probability of being spam. This is measured according to hundreds of different parameters. Much like Google's infamous search algorithm, no one factor is necessarily a showstopper, but everyone wants the secret formula.

The second entity in control is the reader. Readers often mark messages as spam if they find them irrelevant, unsolicited, or annoying. Email readers are bombarded daily by so much content—most of it unhelpful—that they learn to tune it out. And if they've seen it one too many times, they'll do what they can to be left alone.

If you're smart, you're using a marketing automation tool that notifies you of these incidents so you can give them immediate attention. Most email providers take spam seriously—as abuse, even. If they receive multiple abuse reports about a specific sender, they often block the entire domain until the sender proves its credentials. Without a way to track message delivery, you could be sending hundreds, thousands of emails straight into a compost heap.

Common Mistakes

In the interest of preempting this disaster, it's important to know the common problems that get marketing emails in trouble. You can then build screenings into your workflow that catch liabilities before they damage your reputation. Here are five of the most common mistakes that cause emails to be marked as spam:

Related: 6 Email-Marketing Techniques That Boost Click-Through Rates

1. Inadequate permissions

In order to have email permission, the recipient must have specifically agreed to receive periodic messages or offers. Without this permission, you're sending unsolicited mail, which is a surefire way to get caught in a spam filter. ISPs have gotten better in recent years at detecting permissions. For example, if you send a batch email to a list of purchased contacts, almost any ISP will be suspicious. Purchased lists are one of the easiest ways to be identified as a spammer. Inadequate permission can also happen if you email contacts who did give you their email, but didn't specifically opt-in to receive promotions or newsletters (e.g. online customers).

Many email marketing services now establish permission through a "double opt-in" process," which means the recipients sign up to receive emails, then receive a first email with a confirmation link, and do not receive future emails unless they click the link or reply directly.

Related: 6 Reasons Customers Aren't Opening Your Emails (Infographic)

2. Sending emails with spammy content

The actual content of your emails, including the message body, links, images, and headers, can all be factors that rank for spam, if you aren't careful. Here are a few things to to avoid:

  • Hashbusting: using special characters designed to break up words or phrases (e.g. "Fr3e W!nn@r").
  • Bad links: Avoid linking to unreputable sites or content, or using url shorteners.
  • Misleading subject lines: using "Re:" or "Fwd:" when you've never communicated with a recipient before.
  • Sloppy html code: Using Microsoft Word to design in html can add extra formatting to the code, which raises your spam score (and also makes your emails look terrible).
  • Too much image, not enough text: embedding text inside of images or sending emails that are all-image, no text.
  • Using all-caps WHEN it's not NECESSARY: makes your message seem salesy and possibly suspicious.

3. Legal violations

The CAN-SPAM Act of 2003 imposes legal requirements on commercial email, and ISPs will usually weed out sales/promotional content that violates any of these restrictions—not to mention, your business could be fined thousands of dollars for a violation. Here are a few of the most important points to check:

  1. An "unsubscribe" option must be visible in all emails (and must work for 30 days after sending)
  2. You must honor unsubscribe requests within 10 days
  3. From-addresses (e.g. must be accurate
  4. Subject line must be relevant to content
  5. You must include a physical mailing address

4. Unauthenticated sender ID

This can happen when an agency is trying to send out emails using its own server. ISPs usually authenticate sender identities to make sure messages are coming from a legitimate source. The two current standards for this are DKIM (domain keys identified mail) and SPF (sender policy framework), both of which are difficult to set up manually. When an agency sends marketing emails using an email marketing service middleman (such as Salesforce Marketing Cloud or Pardot), the service establishes authentication for you. It's also important to use clear, straightforward "From" field names, such as "updates@," or "newsletter@." You know, something a human would create.

5. Not appealing to the recipient

According to Experian, 60 percent of marketers don't let customers choose the kind of email they want to receive, and only 30 percent let them choose how often they want to receive correspondence. As we mentioned earlier, ISP filters aren't your only threat for being marked as spam. The other half is the customer (or prospect, contact, etc.). To avoid rejection, marketers need to make sure every message proves its own relevance and value, and that the customer understands why they're receiving it.

  • Don't send a promo to a contact you haven't reached out to in eight months (generally, permission goes stale in about six).
  • Don't continue to send newsletters to contacts who are repeatedly deleting them without opening.
  • Don't send messages four times a week if your opt-in form said "occasional" updates.
  • Do use engaging, accurate, personal subject lines.

There are a lot of places where a perfectly harmless email can go wrong. That's why most businesses with email campaigns rely on some kind of marketing automation software, which can analyze your emails, permissions, and authentication, and help you avoid these mistakes.

The good news is, if you're sending solicited, meaningful content, you'll probably steer clear of the spam folder by default. So instead of wringing your hands about landing in the inbox, focus on delivering high-quality emails that delight and engage your readers.

Related: How to Write Better Emails (Infographic)

Aleksandr Peterson

Technology Analyst at TechnologyAdvice

Aleksandr Peterson is a technology analyst at TechnologyAdvice. He covers CRM, marketing automation, project management, and other emerging business technology.

Editor's Pick

Related Topics

Business News

He Won the $2 Billion Powerball Jackpot. Now He's Snatching Up Swanky Homes Across Los Angeles.

Thirty-one-year-old Edwin Castro took his winnings as a lump sum.

Operations & Logistics

3 Ways Logistics Leaders Can Edge the Competition by Embracing Industry Problems

Success often comes to those who stay focused on the problems they're trying to solve, rather than getting fixated on their solution.


Don't Be a Boring Brand – How to Create Brand Distinction That Has Everyone Turning Their Heads

In the minds of most consumers, you're selling commodities — unless you've created a brand distinction. This article will show you how to craft a brand that's not just known but unforgettable.

Business News

Dads Who Do This Simple Activity With Their Kids for 10 Minutes a Day Are More Likely to Raise High Achievers

The straightforward approach can give children an advantage over their peers.

Business News

Taylor Swift Reportedly Pays All Restaurant-Goers' Checks to Clear Out Restaurant For Her and NFL Star Travis Kelce

The star was spotted at Arrowhead Stadium for the Kansas City Chiefs game Sunday night alongside Kelce's mother.

Business News

Costco Is Now Offering an Additional Exclusive Perk to Members in All 50 States

Members can now access discounted outpatient medical care through a partnership with healthcare startup Sesame.