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Avoiding the Spam Folder: Email Marketing Best Practices

Having trouble sending out your eNewsletter, or donations requests via email? Do you keep getting bounce-backs that say your email looks like spam? Sending bulk email can be challenging and can require several rounds of painstaking trial and error before you get it just right. Well, we want to save you some of that pain! Here are five things you can do to avoid being flagged as spam and ensure as many of your emails as possible are making it to the intended recipients:

Have a recognizable “From” or “Sender Address”

Make sure the “from” line contains your organization’s name, so recipients can identify who the email is coming from. If the recipient doesn’t recognize you, they will likely flag you as spam and you don’t want that. Also, make sure the “from” line is consistent to build your sender reputation.

Avoid using spammy words and phrases

Certain types of words/phrases in the subject line or body of your email will set off spam detectors. Words like “FREE” or “BUY NOW” in all-caps, for example, are a bad idea. Spam filters maintain a list of spam word and phrases, along with suspicious formatting. They use this list to analyze your email, assigning points each time they occur. Here’s a sample of some spammy phrases targeted by Spam Assassin (one of the most popular spam filters out there) and the associated points:

  • Contains urgent matter (.288 points)
  • Describes some sort of breakthrough (.232 points)
  • Talks about lots of money (.193 points)
  • Asks you to click below in capital letters (.135)
  • Talks about ‘acting now’ with capitals (.222)

This is just a small sample. For Spam Assassin’s complete list of targeted words, phrases, and formatting, click here. Of course this list changes constantly as spam detectors learn more and more about what junk mail looks like. To test your email to make sure it will pass spam detection, try out this great tool from Lyris.

Test and test again.

Before you send out your email to your entire list, it’s a good idea to do a “dry run.” You can create a couple of dummy accounts using different email services (e.g. hotmail, gmail) and send your message to them first. If your email ends up in the junk folder, or doesn’t get delivered at all, you know you’ve got some work to do.

Include an option to unsubscribe

Make sure each of your emails includes an option to unsubscribe, and respond to all unsubscribes promptly. Failure to do this will most certainly result in reports against you.

Clean bad emails regularly.

When you send bulk email, some will bounce back: you will get a response indicating why the email was not delivered. Look through your bounces, and read the replies. Spam filters usually indicate why they blocked your message. The challenge is determining which are hard and which are soft bounces.

A hard bounce is an email message that has been returned to the sender and is permanently undeliverable. Causes include invalid addresses (domain name doesn’t exist, typos, changed address, etc.) or the email recipient’s mail server has blocked your server.

soft bounce is an email message that gets as far as the recipient’s mail server (it recognizes the address) but is bounced back undelivered before it gets to the intended recipient. A soft bounce might occur because the recipient’s mailbox is full, the server is down or swamped with messages, or the message is too large.

Here is a list of SMTP error messages that will help you interpret bounce-backs. Hard bounces, especially ones that indicate the address is wrong or invalid (e.g. “550 Account is not active”) should be dealt with right away. If you’re using Sumac, you can create a Communication Preference like “Bad Email Address” so that hard bounces can be quickly marked to ensure no more email will be sent to that address. This is very important. Continuing to send emails to bad addresses is guaranteed to set off spam detectors and will increase your chances of being blacklisted.

Avoid getting blacklisted at all costs. Getting yourself off that list can be very difficult! If you are being issued a new IP address, be sure to check its reputation before sending email. In some cases Internet Service Providers or email hosting services will assign you an IP address that already has a bad reputation for sending spam, and has already been blacklisted. To check you IP’s reputation, you can use a service like MXToolbox’s DNS Blacklist Check.


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