Email Security 101: How to Add Email to Safe Sender List

Are you repeatedly failing email deliverability tests?
Mailbox providers incorporate advanced techniques like content analysis, machine learning, and sender reputation scoring inside spam filters to reduce spam mail hitting their customers’ inboxes.
Sometimes, these measures are a bit too effective; they occasionally stop legitimate emails from reaching the inbox. However, using a safe sender list lets users create a rule to allow certain senders to email them, regardless of the content of the message.
But how does a safe sender list work? Why was this feature introduced? And how to add email to trusted senders list?
And if you’re an email marketer, what can you do to improve email deliverability? It can’t be fun to repeatedly ask recipients to add you to their safe senders list. Depending on safelist email marketing would take you decades to build an audience!
Before you drop a bag of money on expensive email deliverability services, read our comprehensive piece on how to become a safe sender.
What is a Safe Sender List?
Whitelisting and blacklisting are email filtering techniques. They are used to control which emails are allowed to be delivered to a recipient’s inbox and which ones are blocked or sent to a spam folder. These techniques protect against spam, phishing, and other unwanted or malicious content.
Whitelisting
Whitelisting explicitly allows certain email addresses, email domains, or IP addresses to bypass spam filters and reach the recipient’s inbox.
Typically, users or email administrators create a whitelist by specifying specific email addresses, domains, or email IP addresses that should always be accepted.
Email users can use whitelisting for important contacts, friends and family, or for specific email marketing newsletters, to ensure such emails aren’t marked as spam. You can simply add an email address to safe sender list to ensure consistent inbox placement.
Blacklisting
Blacklisting is the process of blocking or filtering out emails from specific senders, domains, or IP addresses.
Blacklists are commonly used to block known spammers, email addresses associated with phishing attempts, or domains known to distribute malware. Mail providers such as Gmail, Yahoo, and Outlook often maintain and update blacklists regularly.
These techniques are not mutually exclusive, as both can be used in combination to create a powerful email filtering system. For example, email administrators in companies use a combination of whitelisting and blacklisting — the former to ensure important business emails get through and the latter to block known sources of spam and malware.
What is a Safe Senders List?
Adding someone to your email safe sender list, also known as a trusted sender list, is a method of whitelisting.
Spam filters typically block emails from IPs/domains with poor email sender reputation. Adding an email address or domain to your safe sender list signals your email provider you consider such emails to be trustworthy.
Let’s look at how safe sender lists are useful:
- Prevents false positives: Having a safe sender list is useful in preventing false positives, as email security systems are not perfect and sometimes mark legitimate emails as spam.
- Prevents communication issues: It also helps manage important emails — if you regularly receive important communication from specific individuals, organizations, or services, adding their email addresses or domains to your safe sender list ensures you don’t miss critical information.
- Control your email experience: You can choose which senders or domains you trust and want to receive emails from, even if they would otherwise be flagged as spam.
While a safe sender list can help ensure important emails reach your inbox, it’s essential only to add email addresses or domains you genuinely trust. Adding malicious or spammy addresses could expose you to harmful content.
Let’s now learn more on how to add email to safe sender list.
How to Add Emails to Safe List
Beyond adding a sender to your contacts, some email providers offer advanced filtering options. You can create rules to automatically move trusted emails to your inbox or customize spam settings to allow specific addresses.
These options help ensure you never miss important messages. Let’s learn more about the process of adding an email address to a safe sender list.
Note that you don’t have to turn on safe list, it starts working the moment you add an email address to it.
How to Add an Email Address to Your Safe Senders List
When you add email to safe list, you ensure important messages don’t end up in your spam or junk folder. This process tells your email provider to trust emails by creating a safe senders and safe recipients list.
In most email clients, you can do this by:
- Adding the sender to your contacts: Most email providers prioritize messages from saved contacts, reducing the chances of them being marked as spam.
- Marking an email as “Not Spam”: If a trusted email has landed in your spam folder, marking it as “Not Spam” or “Not Junk” helps train your email provider to recognize it as safe.
- Adjusting safe sender settings: Some email clients allow you to manually add an address to a designated safe senders list to ensure their emails always reach your inbox.
The exact steps vary by email provider. Up next, we’ll walk you through how to do this in Gmail, Outlook, and Hotmail. Let’s begin with how to mark an email safe in Gmail and how to add a domain to Gmail safe list.
How to Add to Safe Senders List in Gmail
So what is safe sender list in Gmail?
You’d be surprised to know Gmail doesn’t really offer users a safe senders list.
Instead of offering a traditional “safe sender” list like other email clients, Gmail lets users achieve similar functionality using a different method: They must create filters to guarantee emails from specific senders or with specific criteria always reach Gmail’s Primary inbox.
To know how to mark as safe sender in Gmail, you must first understand filters.
How to Add Emails to Safe Sender List Gmail Using Filters
These steps don’t apply just to senders; they also show you how to add a domain to safe senders list in Gmail.
Here’s how to set up filters in Gmail:
- In the upper-right corner of your Gmail inbox, you’ll see a gear icon. Click on it to access the “Settings” menu.
- From the dropdown menu that appears when you click the gear icon, select “See all settings.”
- In the Settings menu, click on the “Filters and Blocked Addresses” tab.
- Scroll down to the bottom of the page under the “Filters and Blocked Addresses” section and click on the “Create a new filter” link.
- In the “From” field, you can enter the email address of the sender you want to ensure always reaches your inbox. You can also add additional criteria, such as specific keywords in the email subject/body.
- After specifying your filter criteria, click the “Create filter” button in the bottom right corner.
- In the next screen, you’ll see various actions you can apply to matching emails. To ensure emails from the specified sender always reach your inbox, check the box next to “Never send it to Spam.” You can also modify other rules for your filter, like applying a label or forwarding emails.
- Once you’ve configured your filter criteria and chosen the desired actions, click the “Create filter”
- button.
- Gmail will now confirm your filter has been created. Click the “Create filter” button again to finalize the filter.


And that’s how to add email to Gmail safe list! You can add as many contacts as you like to your safe list in Gmail.
How to Create Safe Sender List in Gmail
To create a Safe Sender list in Gmail, you can’t directly create a list. Instead, mark senders as “Not spam.”
When an email arrives from a trusted sender in your spam folder, open it, click “Report not spam,” and future emails from that address will land in your inbox. As long as you know how to add senders to your contacts, you know how to add sender to safe list in Gmail.
How to Add Safe Addresses in Gmail
To receive emails in your Gmail inbox without problems, you must know how to mark email as safe in Gmail or how to add an email to safe sender list Gmail.
The simplest way to achieve it is to create a filter, as demonstrated in the section above.
Follow these steps to achieve this:
- Go to Settings (gear icon) > See all settings > Filters and Blocked Addresses > Create a new filter.
- Enter the sender’s email address in the “From” field. Click “Create filter” and choose “Never send it to Spam.”
This ensures their emails bypass the spam filter. If you’re curious about how to add an email to the safe senders list in Gmail, the filter method is the best.
We have covered in Gmail how to add email to safe list, so let’s explore Outlook next.
How to Add Email Address to Safe Sender List in Outlook
Outlook is an integrated email, calendar, and personal information management app developed by Microsoft and used by millions of people across the world. Below, you will see how to add an email to your safe sender list in Outlook so you can receive messages without issues.
Outlook App on Mac

Follow these steps to add a safe sender in Outlook on a Mac:
- First, open up your Outlook app.
- Look at the top of the window and click on the “Outlook” tab.
- Then, click on the “Junk” button.
- Here, you have two tabs — Blocked Senders and Safe Senders. Click on the Safe Senders tab.
- This is where you whitelist emails. Click the “+” button at the bottom and type in the email addresses or even entire domains you want to trust. For example, you can add “travis@campaignrefinery.com.” You can also add domain to safe senders list.
- Once you’ve added the safe sender email addresses or domains you trust, close the Outlook safe senders settings window to save your changes.
Outlook on the Web (Outlook.com)

To add a safe sender on the web version of Outlook, follow these steps:
- Start by opening your web browser and going to Outlook.com.
- Log in to your Outlook account.
- Look for the gear icon in the top-right corner of the Outlook.com page and click on it — these are your main Outlook settings.
- Next, head over to the “Junk Email” section.
- In the “Safe senders and domains” section, click the “+ Add” button. For instance, you can add “example@campaignrefinery.com” and hit the Enter key.
- After you’ve added the email addresses or domains you trust, don’t forget to click “Save” to make your changes stick!
Using these methods, your contacts will be able to email you without any issues. Be cautious when whitelisting entire domains though; not all senders from a domain may be as ethical as a known contact.
Where is Safe Senders List in Outlook?
The location of the Safe Senders List in Outlook varies slightly depending on whether you’re using the Outlook desktop application or Outlook on the web.


For example, in the Outlook Mac app, you’ll have to open Settings and find it within the “Junk” folder. Safe senders are listed under the “Safe Senders” tab.


In Outlook on the web, it’s located in the “Junk email” settings, specifically under the “Safe senders and domains” section. Essentially, it’s always within the junk email settings, allowing you to specify trusted senders.
How to Add an Email to Safe Sender List Hotmail

Hotmail has been rebranded as Outlook.com, meaning the process for managing safe senders is now handled within the Outlook interface. Users can still log in with their Hotmail credentials.
To add a sender, go to Settings (gear icon) > View all Outlook settings > Junk email. Here, you’ll find “Safe senders and domains.” Add the desired email address or domain.
The user interface remains consistent, ensuring a seamless transition for former Hotmail users.
How to Add Safe Senders on Different Platforms and Email Clients
Different email platforms have unique steps for adding safe senders. Below are quick instructions for some of the most commonly used email clients.
Apple Mail on Mac

Open an email from the sender you want to whitelist. Right-click their email address and select Add to Contacts or Add to VIPs to prioritize their messages in your inbox.
Apple Mail on iPhone

Open an email from the sender, tap their email address at the top, and choose Add to Contacts. This helps Apple Mail recognize them as a trusted sender.
Office 365
Office 365 uses Outlook as its email service. Refer to our Outlook section above for detailed steps.
Go to Outlook on the web, click the settings gear icon, and select View all Outlook settings. Under Junk email, add the sender’s address to the Safe senders and domains list, then save your changes.
Mozilla Thunderbird

Click the Address Book icon, then select New Contact and enter the sender’s email address. You can also mark an email as Not Junk to help train Thunderbird’s spam filter.
Yahoo

Open an email from the sender, click the More option (three dots), and select Add sender to contacts. You can also go to Settings > Filters to create a rule that moves their emails directly to your inbox.
How to Email Subscribers Without Joining Their Safe Sender Lists
If you’re constantly wondering why your emails go to spam, it may be because you’re repeating common mistakes email marketers make. Sending emails without addressing them will make you look untrustworthy.
Luckily, many of such issues are fixable.
A good example would be unsolicited emails. Nobody likes them; a good way to avoid annoyed recipients would be to use a double opt-in method during signups to add them to your email list.
This is a list of the 7 most common mistakes marketers repeat and included solutions for them:
Issue | Resolution |
---|---|
You’re a spam email sender | Get explicit permission before emailing your recipients, always send relevant content, and make it easy for recipients to unsubscribe. |
Your email bounce rates are high | Regularly clean your email list, remove invalid addresses, and use double opt-in methods to validate new signups. |
Your email delivery rates are low | If your emails are being marked as spam, it indicates an issue with your email sender reputation, which is tied closely to your IP and domain reputation. |
You’re breaking unsubscribe laws | Compliance with laws such as CAN-SPAM and GDPR is critical; avoiding such guidelines can lead to being marked as spam. |
Your email engagement is poor | Step one is good list segmentation. Next, improve your email content and subject lines, and send frequency. |
You don’t use email security protocols | Ensure proper email authentication (like SPF, DKIM, and DMARC) is set up for your domain and you use SSL/TLS. |
You use unreliable Email Service Providers | Choose a reputable ESP with a good sending infrastructure and a commitment to email deliverability best practices. |
Campaign Refinery Makes You a Safe Sender
Instead of constantly asking your readers/email recipients to add you to the safe sender list, you can avoid all the issues in the above table by simply signing up with a reputable and elite email platform such as Campaign Refinery.
Using our email platform will ensure you’re always on your email marketing subscribers’ safe sender list!
Joining hands with Campaign Refinery unlocks these perks:
- Excellent deliverability: Joining Campaign Refinery ensures your email deliverability is at its best as your email content hits recipients’ inboxes rather than being marked as spam or bouncing.
- Sender reputation: Domain reputation and IP reputation, and by extension, your sender reputation, are critical to prevent your emails from being tossed into the spam folder. At Campaign Refinery, we designed our email platform to offer the best tools and software to elevate your sender reputation and let it shine. Additionally, we also implement best practices and only onboard vetted clients, which benefits you as the shared IP pool remains free of spam senders.
- Email list management: Manually cleaning lists is history; Campaign Refinery comes with automated list cleaning, which gets rid of spam traps, invalid emails, typos, and dormant accounts.
- Thousands of templates and a simple UI: We offer a variety of email campaign templates and design tools to simplify the creation of professional-looking emails; no need for extensive HTML coding or design skills.
- Automate your campaigns: Campaign Refinery offers simple automation controls to set up email sequences based on triggers, user behavior, or specific events.
- Analytics: Our reporting tools help you track critical email campaign metrics, providing insights into open rates, click-through rates, conversions, and more. This data helps you refine your strategies for better results.
- Security compliance: At Campaign Refinery, we insist our customers use security protocols like SPF, DKIM, and DMARC on their domains and send emails via SSL connections.
- Integration with third-party tools: Don’t want to let go of your favorite plugin? Campaign Refinery supports native and Zaiper integration with thousands of popular plugins email marketers love.
Ready to discover what it’s like to send emails from the #1 email deliverability platform in the world? Apply here to be a customer!
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FAQ
Which Email Feature Allows You to Mark Certain Senders as Safe So That Their Emails Are Not Filtered Into the Spam Folder?
The Safe Senders list feature allows you to bypass spam filters. Add email address to safe senders list to ensure their emails come through without issues.
Where is Safe Sender Settings in Outlook?
Safe sender settings are typically found within your email client’s junk or spam options.
How to Whitelist an Email?
To learn how to mark someone as a safe sender in Gmail, read the whitelisting section above. Whitelisting involves adding an email address or domain to your safe senders list.
How to Add an Email as a Trusted Sender?
Adding a trusted sender means adding them to your safe senders list. When you add a contact to Gmail, you automatically add them to a trusted senders list. That’s how to add email to safe sender list Gmail.
How to Mark an Email Sender as Important?
Marking a sender as important often involves using features like starred contacts or priority inbox.