Why does Gmail mark emails from new domains as spam?
Matthew Whittaker
Co-founder & CTO, Suped
Published 7 Aug 2025
Updated 16 Aug 2025
7 min read
Starting with a new email domain can feel like a fresh start, full of promise and the anticipation of reaching your audience. Then you send your first few emails, often just to test or for initial outreach, and they land straight in the spam folder. This experience can be incredibly frustrating, especially when you are sure your emails are legitimate and you have taken all the necessary steps to set things up correctly.
The immediate reaction might be confusion, as you wonder why your brand new domain is already being flagged. The reality is that Gmail and other mailbox providers are inherently cautious of new domains. This caution stems from their primary goal, which is to protect users from unwanted mail, phishing, and spam. Without any sending history, a new domain is viewed with suspicion, leading to its emails often being routed to the spam or junk folder by default.
The inherent challenge of new domains
When you register a new domain, it comes with a clean slate, but this lack of history is precisely why mailbox providers like Google are wary. Think of it like a new person moving into a tightly-knit community. Until they establish a reputation through consistent, positive interactions, they are viewed with a degree of caution. Mailbox providers operate similarly. They rely on historical data to assess sender trustworthiness, and a new domain simply has none.
New domains are a popular choice for spammers who constantly cycle through them to bypass filters. As a result, mail servers often treat emails from unestablished domains as suspicious until proven otherwise. This default behavior means that even a perfectly legitimate email from a new domain can initially be flagged as spam.
Sometimes, you might even encounter confusing messages, such as "you've previously marked emails from [your domain] as spam" even if you have never sent from the domain before. This often happens because the domain may have been previously owned by a sender with a poor reputation, and that negative history can linger, affecting your initial deliverability. It's a humorous yet frustrating glitch in the system.
Fundamental authentication and DNS records
For any domain, new or old, robust email authentication is non-negotiable for deliverability. This includes setting up SPF, DKIM, and DMARC records. These protocols verify that your emails are legitimately coming from your domain and have not been tampered with. Without them, your emails are much more likely to be flagged as spam, regardless of your domain's age.
Gmail, Yahoo, and Microsoft have recently tightened their sender requirements, particularly for bulk senders. A key part of these new rules is the mandatory implementation of DMARC. If your domain lacks proper authentication, it signals to receiving servers that your email's authenticity cannot be verified, making it a prime candidate for the spam folder. This is even more critical for a new domain trying to establish trust.
DNS record configuration for new domains
Ensure you have correctly configured your SPF, DKIM, and DMARC DNS records from day one. Some providers, including Google Workspace, may have a slight delay (e.g., 48 hours) before new DKIM records are fully recognized. During this period, your emails might still experience deliverability issues, even if the records are technically correct. Patience and verification are key.
Even with correct authentication, initial emails from new domains may still face challenges. This is where monitoring your DMARC reports becomes critical. These reports provide insights into how your emails are being authenticated and handled by receiving servers, allowing you to quickly identify and fix any authentication failures. Here's a basic example of a DMARC record:
Ignoring these foundational steps can lead to persistent deliverability issues, pushing your emails into the spam folder repeatedly. It's not enough to just have these records, they must be correctly implemented and actively monitored.
Cultivating domain reputation through warming
Domain reputation is like a credit score for your email sending. It's a measure of how trustworthy your domain is perceived by internet service providers (ISPs). A new domain starts with a neutral, or often low, reputation because it has no history of sending emails. This means ISPs have no data to assess its legitimacy. Building a positive reputation takes time and consistent, good sending practices. This process is commonly known as domain warming.
Warming up a new domain involves gradually increasing your sending volume over several weeks or months. You start by sending a small number of emails to highly engaged recipients and slowly scale up. This allows ISPs to observe your sending behavior and see positive engagement signals, which helps build trust in your domain over time. Rushing this process by sending large volumes too quickly is a common mistake that can backfire, leading to immediate spam flagging.
The aim is to demonstrate consistent, legitimate sending patterns. If your domain is new or has a low reputation, ISPs might also apply stricter filtering until enough positive history is accumulated. This is why you often see emails from new domains landing in spam initially.
Good warming practices
Gradual increase: Start with low volumes to highly engaged subscribers.
Consistent sending: Maintain a steady sending cadence without large gaps.
Engaged lists: Focus on lists with high open and click rates initially.
Sudden volume spikes: Sending too many emails too soon from a new domain.
Unengaged lists: Sending to old or bought lists, leading to high bounces/complaints.
Ignoring warnings: Overlooking spam reports or low reputation scores.
Inconsistent sending: Erratic sending patterns that look suspicious to ISPs.
Establishing a strong domain reputation requires patience and adherence to best practices. Skipping the warming-up phase or sending large volumes immediately from a new domain almost guarantees that your emails will land in the spam folder, or even result in your domain being added to a blocklist (or blacklist).
Content quality and recipient engagement
Beyond technical setup and domain age, the content of your emails plays a significant role in deliverability. Spam filters analyze various elements, including subject lines, body text, links, and images, to identify potentially unwanted or malicious content. Using spam trigger words, excessive capitalization, or misleading subject lines can immediately flag your emails, especially when sent from a new domain with no established trust.
Recipient engagement is also a critical factor. When recipients open, click, and reply to your emails, it sends positive signals to ISPs like Gmail, indicating that your content is valued. Conversely, a lack of engagement, or worse, recipients marking your emails as spam, will severely damage your domain's reputation. This is why sending to an old or unverified list can lead to high bounce rates and spam complaints, particularly for a new domain trying to establish credibility.
Even factors such as poor email design, which results in emails rendering incorrectly, can increase the likelihood of recipients marking your messages as spam. Ensuring your content is relevant, personalized, and properly formatted for various email clients is crucial for maintaining positive engagement and improving deliverability from your new domain.
Views from the trenches
Best practices
Always warm up new domains gradually, starting with small volumes and increasing over time.
Ensure SPF, DKIM, and DMARC records are correctly configured and monitored from day one.
Segment your audience and send to your most engaged subscribers first during the warming period.
Common pitfalls
Sending a large volume of emails immediately from a brand new domain without a warming phase.
Failing to implement or misconfiguring essential email authentication protocols like DMARC.
Using purchased or unverified email lists, leading to high bounce rates and spam complaints.
Expert tips
Verify that your email sending infrastructure (e.g., ESP, SMTP) is properly aligned with your domain and its authentication.
Understand that shared IP addresses can initially influence a new domain's reputation, for better or worse.
Analyze email headers for insights into deliverability issues, even when the displayed spam message seems irrelevant.
Marketer view
Marketer from Email Geeks says that a freshly registered domain had its first email sent to a Gmail inbox, which was immediately marked as spam, displaying an incorrect message about previous spam reports.
2021-04-08 - Email Geeks
Marketer view
Marketer from Email Geeks says that sending emails from freshly registered domains is generally not recommended, suggesting a waiting period of at least 30 days before initiating sending.
2021-04-08 - Email Geeks
Building trust for new domains
Having your emails marked as spam by Gmail when using a new domain is a common challenge. It's not a reflection of your email content or intent, but rather a protective measure by mailbox providers against potential abuse. Overcoming this hurdle requires a strategic approach that focuses on building trust and demonstrating legitimate sending behavior.
By prioritizing proper email authentication (SPF, DKIM, DMARC), diligently warming up your domain, and consistently sending valuable content to an engaged audience, you can progressively improve your deliverability. Patience and vigilance are key to ensuring your new domain earns its place in recipients' inboxes.
Gmail and other mailbox providers are inherently cautious of new domains. This caution stems from their primary goal, which is to protect users from unwanted mail, phishing, and spam. Without any sending history, a new domain is viewed with suspicion, leading to its emails often being routed to the spam or junk folder by default.
Google are wary. Think of it like a new person moving into a tightly-knit community. Until they establish a reputation through consistent, positive interactions, they are viewed with a degree of caution. Mailbox providers operate similarly. They rely on historical data to assess sender trustworthiness, and a new domain simply has none.
Yahoo, and 
Microsoft have recently tightened their sender requirements, particularly for bulk senders. A key part of these new rules is the mandatory implementation of DMARC. If your domain lacks proper authentication, it signals to receiving servers that your email's authenticity cannot be verified, making it a prime candidate for the spam folder. This is even more critical for a new domain trying to establish trust.
Google Workspace, may have a slight delay (e.g., 48 hours) before new DKIM records are fully recognized. During this period, your emails might still experience deliverability issues, even if the records are technically correct. Patience and verification are key.
