Email Marketing Best Practices

The rules of email marketing have changed, and what used to work may not work any longer. Internet Service Providers are becoming increasingly sophisticated, and are getting better at stopping spam and bulk email campaigns. Because of this, we’ve put together a list of best practices to help you achieve the best possible results with your email campaigns.

Step 1: Only send email to people who want to receive it

Email marketing campaigns should only be sent to people who knowingly signed up to receive email. Otherwise, people may consider your messages spam.

Why it’s important

People have opted in only if they requested regular emails, for example by checking a box on a form that says “I would like to receive email messages.”

Even if your list is made up of people who purchased a product from your site or signed up for a membership account, if they did not explicitly indicate that they would like to receive regular email correspondence, it’s possible that they will consider your email campaigns spam. If enough people click on the “This message is spam” button in their email accounts, you could get blacklisted by one or several internet service providers. At that point, none of the users of that ISP will receive your emails, including those who have opted in.

What you can do

  1. Only send to people who have opted in. If people fill out your “enews” form, they’re requesting to receive email correspondence, so it’s safe to include these people in your distribution lists. But for other forms, for example a “Contact Us” form, you should include a checkbox saying “I would like to receive email messages.” Then, when selecting your distribution list for an email campaign, select the “Contact Us” group in the Forms section, and click on the “Edit Conditions” button below. You can edit the conditions so the campaign is only sent to those people who checked the opt-in checkbox.

  2. Include an unsubscribe link. You should also include an unsubscribe link at the bottom of every email you send. If people are given this option, they are much less likely to mark your emails as spam. You can easily add an unsubscribe link to your campaigns by embedding it into your email marketing templates. This can be done on the Email Marketing module’s Templates tab: Edit a template, then locate the HTML Body section. Place your cursor into that section where you want to insert the link, then from the “Insert Field” drop-down menu, select unsubscribe_url.

  3. Do not use purchased, borrowed or "inherited" lists. If your list was acquired from someone else, it's clearly not a list of people who opted in to receive your email. Moreover, some purchased lists can contain "spam trap" addresses, which are invalid addresses retained by ISPs to find people who send to non-opt-in lists and identify them as spammers. Sending to a single one of these "poison" email addresses can pollute the reputation of your entire campaign.

  4. Consider the age of your lists. If your list is months or years old, people may no longer be interested in receiving your emails. Many ISPs recommend sending periodic reconfirmation requests to aging email addresses to ensure that these recipients still want to receive email from you. It's better to remove non-respondents than risk them marking your email as spam.

  5. Gauge the interest in your campaigns. Using Freedom's campaign tools, you can determine which users aren't viewing your campaigns and how your campaigns are performing overall. You can do this on the Campaigns tab by selecting the History subtab. Consider reaching out to users who never view your mail and attempting to reconfirm their interest. Also, check to see if many people are unsubscribing from your campaigns. If many people are doing so, it's a good sign that your campaigns are unwanted and likely to be considered spam.

Step 2: Perform maintenance on your subscriber lists

Sometimes an email address is entered into Freedom incorrectly, or a person on your list changes his or her email address, meaning that the one you’re sending to no longer exists. These emails will not be successfully delivered.

Why it’s important

If your campaigns have too many undeliverable emails, this can slow down the sending of campaigns, or even crash your website.

If an email can’t be delivered, it’s put back in the queue, and the system tries again later. If you’re sending to valid lists, this works well. However, if you’re sending to hundreds or thousands of invalid email addresses, or to domains that have blocked you because they consider you a spammer, your queue can quickly fill up with these emails that will never be delivered. As a result, campaigns may take a very long time to complete, and this can overwhelm your server’s resources.

What you can do

  1. Check your bounced emails. The Email Marketing module has a Bounced tab where you can view all of the email addresses that the system tried unsuccessfully to deliver email to. This tab shows you how many unsuccessful attempts there have been for each address, and sometimes provides an error code to indicate why the email was not delivered. 

    When you send out a campaign, undeliverable emails first go into a bounced email account. To view those emails on the Bounced tab, click on the blue “Get Bounced Emails” button. We recommend clicking this button before each email campaign you send.

  2. Invalidate bad emails. To stop undeliverable emails from wasting your server’s resources and to avoid risking harm to your reputation, you should invalidate bad emails, either one at a time by clicking the Invalidate links, or all at once with the red “Invalidate All” button.

    1. Invalidate permanent error codes. Most undeliverable email addresses will return an error code, which can give a clue as to why the email was not delivered. 400-level error codes are temporary errors; for example if an email box was full it will return one of these. 500-level errors, on the other hand, are permanent, and in most cases these email addresses should be corrected or invalidated.

      You can filter the list using the “(Code)” drop-down menu to view all of the email addresses that have returned any single error code. We suggest you filter for the error code SMTP; 550 and invalidate all of these addresses. Do the same for SMTP; 554. For other 500-level codes, we suggest that you look at the “Count” column; if an email address has more than five bounces, it should probably be invalidated.

    2. Fix misspellings. In addition, when looking through your bounced email list, if you see misspellings, such as addresses ending with or, these are things that should be fixed or removed. Edit those records and correct the misspellings, then delete them from the bounced list.

Step 3: Make sure you're on the right server

If you send large email campaigns, your website should be running on a powerful server tuned for optimal email marketing performance.

Why it's important

Not all websites have the same hosting needs, and email marketing in particular tends to use a lot of server resources: Sending email to a large list creates sustained, intensive server activity, which consumes processing power and database access and cuts into the network bandwidth available to process web server requests. An upgraded server from Accrisoft is designed to handle large volume email campaigns by providing an increase in RAM, operating system resources and bandwidth.

What you can do

Accrisoft provides three levels of email marketing servers. The more powerful servers not only run campaigns more smoothly and at faster throughput, but also provide more processing power, RAM and storage space. Tell your Solution Provider to contact Accrisoft and match your server to your email marketing needs.

Step 4: Educate your marketing staff

General guidelines:

ISP-specific guidelines:
Ultimately, email recipient servers belong to private entities that can accept or defer/reject your email at their discretion, per their own arbitrary policies and conditions. Below are links to the policy statements of various large email recipients to help you understand what these conditions may be.


If you follow these guidelines, you will greatly reduce the chances of your IP address being blacklisted. Furthermore, your campaigns will be much more likely to be delivered successfully, and your website will be much less likely to run slowly or crash.

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