It’s frustrating when your marketing emails land in the junk folder, or worse, do not reach the intended recipients at all. Here are some basics to email deliverability that will help you avoid such an undesirable outcome.

Email Authentication

Email authentication (SPF and DKIM) is a way to ensure that an Internet Service Provider (ISP), such as Google, Microsoft, AOL or Comcast, will be able to recognize you as a legitimate sender. It also prevents spam, phishing, and abuse. If you have this set up correctly, you’ll improve your likelihood of getting emails through to your intended recipients. Emails that fail to pass authentication checks may be blocked or flagged as junk, potentially preventing them from reaching an inbox.

DMARC is a policy that allows a sender to indicate that their emails are protected by SPF and/or DKIM. It tells an ISP what to do if neither of those authentication methods passes, such as send to the bulk folder or reject the message. DMARC removes much of the guesswork to help minimize email recipients’ exposure to potentially fraudulent and harmful messages.

Pro Tip: ISPs don’t all use the same authentication methods. Typically, one or more of the methods are used to determine the legitimacy of your email. Make sure you set up both SPF and DKIM to ensure email authentication.


There are two types of email bounces: hard and soft. A hard bounce occurs when an email is sent to an unknown user, invalid account, closed email account or nonexistent email address. A soft bounce occurs from a temporary failure, such as the recipient’s mailbox is full, a server is down, or a message is blocked due to the recipient’s settings or because you’ve been blacklisted.

High bounces in any email campaign can be indicative of a larger issue. Hard bounces can be attributed to data hygiene issues, such as poor list collection practices or insufficient list maintenance. Soft bounces may indicate you’ve been blocked. It’s important to identify if a block or network issue has occurred so you can work to resolve it quickly.

Pro Tip: Always ensure you are adequately managing your lists and are using best practices for data collection. Also keep in mind that if you send to too many unknown users, it will have a negative effect on your sending reputation and could drive soft bounces.


Blacklists can be both global – across all ISPs – or local to a specific ISP. A blacklist occurs when your IP addresses and/or domains become known sources of spam. Many ISPs use companies like Spamhaus to manage this effort. ISPs also maintain their own internal blacklists of bad IPs and domains. They’ll check incoming mail against the sending domain and IP address to determine if the address is on their blacklist.

Pro Tip: Getting blacklisted will have a significant impact on your email marketing efforts. You can get blacklisted for a variety of reasons, including sending to people without permission, sending to purchased lists, or receiving a high number of complaints. Getting off a blacklist can be a daunting task. Marketers must be diligent in following list collection and sending best practices to prevent getting blacklisted. Not only will it save you from a terrible hassle, it will ensure your messages continue to reach your target audience.


Spamtraps are emails created by ISPs to catch spammers. They are classified in two categories: honey pots and recycled traps. Honey pots, also known as pristine traps, are email addresses that never signed up to receive email, are not a real person and were created to solely to act as a trap to catch spam. Recycled traps are addresses that once belonged to a person but were abandoned and recycled by ISPs to act as spam traps.

Pro Tip: Ensure you are organically growing your contact list to avoid honey pot traps. Ask for permission to email someone and know they’re a real user before you engage with them. Do not purchase email lists. They are full of spamtrap addresses that will propel you into blacklisting status in no time. Also, be sure to mail frequently to your list and purge old data. If you don’t send frequently, you run the risk of emailing a recycled email address and getting flagged as spam. Be sure to practice good data hygiene.

Feedback Loop

Feedback loops are offered by several ISPs and provide abuse complaints back to a sender. When a recipient clicks, “This is Spam” in their email client, this feedback is sent back to the sender and, for Salesfusion’s, becoming Sugar Market’s, clients, the user is automatically unsubscribed from future mailings.

Pro Tip: Keep complaints low from your users. Send relevant and targeted email to minimize complaints and maximize engagement. Set message expectations at the point of email collection and follow up with a welcome message. Remain transparent about your intentions. Establish trust and provide what your contacts want to receive to keep complaints low.

Keep doing great things with your email marketing programs, but don’t forget the foundation for success is ensuring your emails are delivered and received by your intended recipients.

Click here to learn more about how Salesfusion can help you with email deliverability, or download our Email Deliverability Guide.