Ultimate Guide to Gmail Email Marketing in 2022

Gmail email marketing is one of the most powerful marketing tools for any business. With over 1.5 billion customers, Gmail holds the title as the most dominant email service provider.

To achieve such a prestigious title within email marketing, Gmail had to focus on maximizing its customer experience and develop an advanced filtering system to separate legitimate and malicious emails.

The Gmail Spam Folder does a good job – it keeps junk mail out of our inboxes. Unfortunately, it may sometimes do too good of a job. 1 in every 5 legitimate emails fails to reach the intended Gmail account because of Gmail filters.

Knowing how to reach Gmail contacts in the world’s largest free mailbox provider is crucial for every successful email marketer.

Unlike Outlook and Yahoo, Gmail is a closed-door provider. Therefore, it does not disclose its filtering rules or provide a lot of guidelines and support for email senders.

As such, we’ll try to lead your email marketing program in the right direction when it comes to what Gmail examines and considers in order to make filtering judgments.

In this article, we’ll show you what email marketers should know when sending their marketing campaigns to any Gmail account.

How Gmail Inbox Tabs Affect Email Marketing

Gmail organization

In order for users to manage, sort, and quickly find their messages when using Gmail, Google introduced the following categories in the Inbox: Primary, Social, Promotions, Updates, and Forums.

To sort incoming messages by these categories, Gmail uses an algorithm that analyzes everything from the email content to the recipient’s engagement feedback.

Gmail users can influence which category the email messages are sent in different ways:

1 Use the “Move to” drop-down menu or right-click on the message and select “Move to”. You will immediately have the option to move that specific email to one of the categories mentioned above, the spam folder, the trash, or you can even create a new label for it.

2 Drag and drop an email message into a different tab. Gmail will ask the user if they want all future messages from that sender to go to the selected tab. If the user clicks Yes, all messages from that sender will automatically be placed in the new tab. If no, the messages from that sender will continue landing under the original tab.

3 Star a message. Starred messages will show in the Primary tab and can also be filtered through the ‘Starred’ Folder.

The Gmail Inbox categories add an extra layer of complexity for email senders attempting to send marketing emails to their email list.

Organizing one’s Gmail interface will prevent your messages from being lost in a sea of mass emails being delivered daily. Like with an email placed in the spam folder, a message that isn’t seen where your subscribers were previously able to see it will go unnoticed.

To ensure your emails are placed in the correct category, follow these tips:

1 Send emails with different types of messages (e.g., newsletters, promotions, transaction emails) from different sender email addresses and try to keep those sender addresses consistent over time.

2 Do not mix different types of content in one message. Avoid having multiple goals for your email campaigns. For example, adding a promotion to an account confirmation email may cause the message to be placed in Promotions.

Gmail Spam Filtering versus Email Marketing

To differentiate between good emails and “spammy” messages, Gmail looks at the following things:

– User Engagement
– Email Content
– Sender Reputation
– Email Infrastructure

How does Engagement Affect Marketing Emails?

User engagement has a huge influence on Gmail’s filtering decisions.

The following positive and negative Gmail user activities are critical for assessing engagement:

 read messages
 replied to messages
 starred messages
 moved to a folder messages
 not spam reports
 spam reports
 deleted without reading messages

Gmail looks at two types of engagement:

  1. A user’s engagement with emails from a particular sender (sender domain)
  2. The general user’s engagement with their mailbox.

Users who interact with emails from a domain for multiple days are more likely to get messages from that domain placed in their Inbox. And users who frequently interact with their mailbox, in general, receive more messages in their inboxes than other users.

It’s important to understand the correlation between these two measures of engagement. Users who are less engaged with your emails than with the rest of their mailbox may have fewer of your messages delivered to their Inbox, even if you consider them an engaged recipient.

Send more personalized emails to your email list. No one likes to receive random, generic emails that may not apply to them. Email marketing efforts that don’t include dynamic variables won’t perform as well as personalized emails.

Email Content Influences Where Your Emails Land

Your email content is correlated with where your emails land in Gmail. They can land in either Primary, Social, Promotions, Updates, Forums, or Spam.

Google filters will label your messages based on their content. They check everything including headers, body, attachments, HTML code, images, URLs, spam keywords, malware, viruses, spam HTML tags, etc.

With the GlockApps spam test, you can check your content with Google Spam Filter, Barracuda, and SpamAssassin to avoid the Gmail spam folder. While Barracuda and SpamAssassin give a detailed report about how the spam score is calculated, the Google Spam Filter returns “Spam/Not Spam” and “Phishy/Not Phishy” without any specific details.

Email Marketer's Guide: What You Need to Know about Gmail

While an email that has been labeled as spam by the Google Spam Filter does not necessarily end up in spam, when other problems like missing email authentication or bad sender reputation are detected, it can make a difference in where it is placed.

Spam filters frequently check email content, but how much attention it is given usually relies on the sender’s reputation.

Importance of Sender Reputation in Email Marketing

Another major consideration that Gmail makes when filtering emails is the sender’s IP and domain reputation. Your sender reputation is directly connected with user engagement.

In order to run a successful email marketing program, you need to have a strong sending reputation. The more positive actions your subscribers take on your messages, the higher your domain reputation will increase, and the more your emails will be placed in your customer’s inboxes.

How can I check my domain and sender reputation?

If your emails consistently land in the Gmail spam folder, create a Google Postmaster account and check your sender domain and sender IP reputation.

Although spam filtering decisions are made based on a lot of factors, the domain and IP reputation allow you to have a sense of whether or not your emails could be considered “spammy”.

Gmail assigns your sending reputation to your domain and IP address based on the number of spam emails you send from that same domain and IP. “Spam” in this context includes emails detected with spam-like content by Gmail’s Spam filter, and how many people report your emails as spam and send them to the spam folder.

How Sender Reputation Impacts Inbox Placement | by GlockApps (G-Lock  Software) | Medium

How does sender reputation affect Gmail Deliverability?

According to the Google Postmaster Tools, the classification for your reputation can be:

Bad — A history of sending an enormously high volume of spam emails. Mail coming from this entity will almost always be rejected at SMTP or sent to Gmail’s spam folder.

Low – Known to send a considerable volume of spam messages to their email list regularly, and mail from this sender will likely be sent to the spam folder in Gmail.

Medium/Fair — Known to send good mail, but is prone to sending a low volume of suspicious emails or spam intermittently. Most of the emails from this email account will have a fair deliverability rate, except when there is a notable increase in spam levels.

High — Has a good track record of legitimate emails, a very low spam rate, and complies with Gmail’s sender guidelines. Mail will rarely be marked by the spam filter.

Gmail is careful about emails sent from IPs without a reputation. It will prevent emails from being sent from new IP addresses for the first 2-24 hours, then it delivers them in small amounts to both the Inbox and the spam folders to see the subscriber’s reactions.

If a lot of complaints happen, future emails from that IP will be delivered mostly to the Gmail spam folder. If more email recipients click “this is not spam” and unmark emails during this period, it means that the email is safe to be delivered to your customers.

To start a reputation for your IP address, start a warm-up process by sending legitimate emails to your verified and most active subscribers. This segment could include people who have opted-in most recently and who are consistently engaging with your emails by opening and clicking your messages.

The more consistently you send and the lower your complaint and bounce rates during the warm-up period, the faster you will establish a positive sending reputation. If you send infrequently, it will take longer to build a positive reputation.

How to Warm up an IP Address

Read this 11-page whitepaper to learn why and how to warm up your new IP
and make sure you’re doing it right.

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Email Infrastructure: Pivotal to Gmail Marketing

Senders with the proper email infrastructure have more chances of delivering their marketing messages to Gmail’s Inbox than senders with a poor email setup.

Your email infrastructure includes the configuration of your sender IP address, domain, and authentication.

To make sure that your important emails are not filtered as spam because of a technical issue, it is recommended that you:

1 Send from the same IP address(es).

2 Send each type of mail from a consistent domain.

3 Set up valid rDNS for sending IP addresses pointing to your domain.

4 Set up DKIM, SPF, and DMARC email authentication.

You can test your DKIM and SPF authentication by running a spam test with our Inbox Insight tool.

Email Marketer's Guide: What You Need to Know about Gmail

Whitelists and Blacklists

Gmail does not maintain their own whitelist, nor do they rely on any third party whitelists.

Gmail does not advertise the use of any public blacklist but it may use signals from Spamhaus.

Here you can read more about why Google can block you and how to get unblocked.

Useful Links

The free resources below can help you follow best Gmail’s email marketing practices and troubleshoot deliverability issues with Gmail:

Bulk Senders Guidelines. Read through the guidelines to learn more about spam classification, email authentication, subscription and unsubscription, and email delivery to Gmail users.

Google Postmaster Tools. In order you can access the information about your sender domain, you need to add and verify your authenticated domain. Once it’s verified, you will be able to access several dashboards: Spam Rate Dashboard, Domain and IP Reputation Dashboard, Feedback Loop Dashboard, Authentication Dashboard, Delivery Errors Dashboard.

Gmail Feedback Loop. Gmail does not offer a traditional FBL service when a complaint report is sent in the ARF format to the sender. Gmail requires a sender to embed the Feedback-ID header, consisting of unique parameters that identify their individual campaigns. The information about spam rate will be then available in the Google Postmaster Tools.

How to Improve Delivery to Gmail Inbox. Here you can find real tips for getting your emails into Gmail’s Primary tab.

Gmail Sends Emails to Spam. How Can I Fix It? From this post, you can learn how to find out why Gmail sends your emails to “Spam” and fix the spam folder placement issue.

Also read: Staying Out of Gmail Spam After the Latest Security Update to learn 10 Tips to improve your Gmail Deliverabilty

Gmail has reached a whole new level of influence in the digital commerce space. With nearly 1.2 billion people using this email inbox, it’s crucial that marketers understand what measures to take when creating a new email marketing campaign and how it affects the way people engage with their emails on both mobile and desktop.

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Julia Gulevich is an email marketing expert and customer support professional at GlockSoft LLC with more than 15 years of experience. Author of numerous blog posts, publications, and articles about email marketing and deliverability.