Why do welcome emails go to spam and how to fix it?

Summary

Welcome emails are frequently flagged as spam due to a multifaceted combination of factors. These include sender reputation issues stemming from low engagement, high bounce rates, spam complaints, and the use of fake email addresses. The content itself plays a significant role, with spam trigger words, unusual HTML, and insufficient text contributing to deliverability problems. Technical aspects such as lacking proper email authentication (SPF, DKIM, DMARC), shared IP addresses, and being listed on blocklists also influence spam filtering. Moreover, problematic signup practices, like not securing signup sources with CAPTCHA or failing to obtain clear consent via double opt-in, exacerbate the issue. Finally, algorithms used by email clients filter emails based on these and other signals. Fixing these issues involves improving list hygiene, implementing robust authentication, enhancing content relevance, securing signup processes, actively monitoring sender reputation, and testing deliverability.

Key findings

  • Sender Reputation: A low sender reputation, influenced by low engagement, high bounce rates, spam complaints, and poor IP/domain history, is a primary cause of welcome emails going to spam.
  • Authentication Issues: Lack of proper email authentication (SPF, DKIM, DMARC) makes it difficult for email providers to verify the sender's legitimacy, leading to spam filtering.
  • Content-Related Triggers: Spam trigger words, unusual HTML, and insufficient text content in welcome emails can activate spam filters.
  • Signup Process Problems: Insecure signup forms without CAPTCHA and the absence of double opt-in lead to bot signups and lower engagement, negatively affecting deliverability.
  • Algorithmic Filtering: Email clients use complex algorithms to determine inbox placement, taking into account numerous factors like engagement, reputation, and content.
  • List Hygiene: Not maintaining a clean email list by removing inactive users or hard bounces negatively impacts sender reputation.

Key considerations

  • Implement CAPTCHA: Add CAPTCHA to signup forms to prevent bot registrations and ensure only legitimate subscribers join your list.
  • Use Double Opt-in: Require new subscribers to confirm their email address through a double opt-in process to ensure valid and engaged recipients.
  • Authenticate Your Emails: Configure SPF, DKIM, and DMARC records to authenticate your sending domain and demonstrate email legitimacy to providers.
  • Clean Up Your List: Regularly remove inactive subscribers, hard bounces, and spam complainants from your email list to maintain a high-quality audience.
  • Review Your Content: Carefully review welcome email content to eliminate spam trigger words, excessive use of caps or exclamation points and optimize the HTML to text balance.
  • Monitor Sending Reputation: Track your sender reputation using tools provided by email providers and address any issues promptly to maintain a positive sending score.
  • Ensure Consent and Transparency: Be clear and transparent with subscribers about what they are signing up for.
  • Check IP Reputation: Monitor your IP reputation and ensure it is not on any blocklists.

What email marketers say
13Marketer opinions

Welcome emails frequently end up in spam folders due to a combination of factors, including low engagement, poor sender reputation, spam trigger words in the content, and inadequate email authentication (SPF, DKIM, DMARC). Additional reasons include subscribers not recognizing the sender, issues with IP address reputation, and HTML content problems. Solutions involve securing signup sources, ensuring clear opt-in processes, improving list hygiene, warming up IP addresses, avoiding spam trigger words, implementing email authentication, segmenting audiences, personalizing messages, and testing deliverability. Also consider that people use junk mailboxes.

Key opinions

  • Low Engagement: ISPs prioritize emails that recipients interact with. Low open rates and click-through rates can lead to spam classification.
  • Poor Sender Reputation: ISPs assess sender reputation based on past sending behavior, including bounce rates, unsubscribe rates, and spam complaints.
  • Spam Trigger Words: Certain words and phrases commonly associated with spam can trigger spam filters.
  • Lack of Authentication: Failure to implement SPF, DKIM, and DMARC can negatively impact deliverability.
  • Unclear Opt-in: If subscribers don't remember signing up or are unsure of what they opted into, they're more likely to mark emails as spam.
  • IP Reputation: A poor IP reputation can cause emails to be blocked or sent to spam. This can be due to previous spam activity from the IP address.
  • HTML Content: Unusual or poorly coded HTML content can trigger spam filters.
  • Junk Mailboxes: Some users use junk mailboxes to access gated content, which can lead to low engagement and spam complaints.

Key considerations

  • Secure Signup Sources: Implement CAPTCHA and other security measures to prevent bot signups and ensure genuine subscribers.
  • Ensure Clear Opt-in: Be transparent about what subscribers are opting into and use double opt-in to confirm their consent.
  • Improve List Hygiene: Regularly remove inactive subscribers, hard bounces, and spam complaints from your email list.
  • Warm Up IP Address: Gradually increase sending volume to establish a positive sending reputation with ISPs.
  • Avoid Spam Trigger Words: Review email content carefully to avoid using words and phrases commonly associated with spam.
  • Implement Email Authentication: Configure SPF, DKIM, and DMARC records to verify your sending domain and improve deliverability.
  • Segment Audiences: Segment your audience to send more targeted and relevant emails.
  • Personalize Messages: Personalize your emails to increase engagement and make subscribers feel valued.
  • Test Deliverability: Use tools like Mail-Tester to test your email content and sending practices before sending to your entire list.
Marketer view

Marketer from Email Geeks suggests that people might be using junk mailboxes to access gated content. Recommends implementing previously suggested fixes to resolve the issue and follow best practices, as pinpointing a single cause is difficult and may prolong the problem.

July 2021 - Email Geeks
Marketer view

Email marketer from Litmus explains that focusing on permission and preference management, authentication, content and reputation are key to ensure deliverability. Use a double opt-in, be upfront about what the user is signing up for, use email authentication (SPF, DKIM, DMARC). Ensure your content is relevant and avoid spam trigger words.

October 2022 - Litmus
Marketer view

Marketer from Email Geeks shares advice on welcome email filtering, suggesting securing signup sources with CAPTCHA, ensuring clarity in opt-in, and avoiding forced opt-ins for marketing content. Also advises checking for high bounces, unsubscribes, or complaints, which indicate reputation issues related to bot signups or unaligned consent. Suggests double-checking the sending domain and authentication.

May 2022 - Email Geeks
Marketer view

Email marketer from ActiveCampaign says reasons for welcome emails ending up in spam include: poor sender reputation, sending unsolicited emails, and spam trigger words. To fix these issues, improve list hygiene, ensure subscribers have opted-in, and review your content.

March 2025 - ActiveCampaign
Marketer view

Email marketer from Email on Acid shares that to improve welcome email deliverability: segment your audience, personalize your message, and test deliverability, so consider what subscribers expect from the email and make sure the content is tailored for them.

April 2024 - Email on Acid
Marketer view

Email marketer from Gmass shares that spam filters may mark welcome emails as spam if you're a new sender, there is too little text, there's no unsubscribe link, it contains spam trigger words, or you're using a shared IP.

August 2021 - Gmass
Marketer view

Email marketer from Mailjet explains that welcome emails often land in spam due to several factors: low engagement (ISPs prioritize emails recipients interact with), poor sender reputation (ISPs assess sender reputation based on past sending behavior), spam trigger words (using words commonly associated with spam can cause filtering), and lack of authentication (not implementing SPF, DKIM, and DMARC can harm deliverability).

April 2021 - Mailjet
Marketer view

Email marketer from StackOverflow shares that if welcome emails are going to spam, check your IP's reputation, ensure proper authentication (SPF, DKIM, DMARC), avoid spam trigger words, and ensure proper list hygiene. Also, test your email content and sending practices with tools like Mail-Tester.

May 2024 - StackOverflow
Marketer view

Email marketer from HubSpot explains welcome emails go to spam because of: low engagement, poor sender reputation, spam trigger words and lack of authentication. Solutions are: Improve email content (make it engaging), increase sender reputation (consistent sending), avoid spam trigger words (review content carefully) and implement authentication (SPF, DKIM and DMARC).

October 2023 - HubSpot
Marketer view

Email marketer from Reddit explains that welcome emails go to spam because of lacking proper authentication, trigger words, and low engagement so the response is to set up SPF, DKIM, and DMARC. Also avoid using too many promotional words and test your emails before sending.

February 2023 - Reddit
Marketer view

Email marketer from SendPulse shares that reasons for welcome emails landing in spam include: subscribers not recognizing the sender, low sender reputation, spam filters, incorrect email structure, and problems with IP address. Suggested fixes include using double opt-in, warming up IP address, checking IP address against blacklists, using email authentication, avoiding spam trigger words, and creating mobile-friendly emails.

May 2021 - SendPulse
Marketer view

Marketer from Email Geeks suggests ensuring there's nothing unusual in the HTML content, such as images hosted on a different domain than the sending IP.

December 2021 - Email Geeks
Marketer view

Marketer from Email Geeks generally says to make sure every email is wanted by the recipient, as filters don't think that's the case now.

December 2024 - Email Geeks

What the experts say
5Expert opinions

Welcome emails often end up in spam because of issues related to signup practices, sender reputation, and content. Specifically, high spam reporting suggests that individuals are signing up and marking the emails as spam. Bounces from Gmail indicate the use of fake or non-existent email addresses, which damages sender reputation. Sender reputation is also affected by IP address history, domain reputation, authentication status (SPF, DKIM, DMARC), and engagement metrics. Using spam trigger words and poor formatting can also cause emails to be filtered. Maintaining a clean email list through regular removal of inactive subscribers, hard bounces, and implementing double opt-in is crucial for improving deliverability.

Key opinions

  • Spam Reporting: High rates of spam reporting suggest that subscribers are either not recognizing the sender or are intentionally marking the emails as spam.
  • Fake Email Addresses: Bounces from Gmail indicate the use of fake or non-existent email addresses, which harms sender reputation.
  • Sender Reputation: Sender reputation is a key factor in deliverability and is affected by IP address history, domain reputation, authentication, and engagement metrics.
  • Spam Trigger Words: Certain words, phrases, and formatting can trigger spam filters and lead to emails being classified as spam.
  • Poor List Hygiene: Failure to maintain a clean email list can negatively impact sender reputation and deliverability.

Key considerations

  • Move Verification Earlier: Implement verification processes earlier in the signup process to ensure that only legitimate subscribers are added to the list.
  • Inform Subscribers: Instruct subscribers to check their spam folder for the welcome email and mark it as 'not spam'.
  • Monitor and Improve Sender Reputation: Continuously monitor sender reputation and take steps to improve it, such as authenticating emails and improving engagement metrics.
  • Avoid Spam Trigger Words: Carefully review email content to avoid using spam trigger words and poor formatting.
  • Maintain Clean List: Regularly remove inactive subscribers, hard bounces, and spam complaints from your email list.
  • Implement Double Opt-in: Use double opt-in to verify email addresses and ensure genuine interest in receiving emails.
Expert view

Expert from Spamresource shares that certain words, phrases, and formatting techniques can trigger spam filters. Examples include excessive use of exclamation points, all caps, and phrases like 'free,' 'guaranteed,' or 'limited time offer.' Review content carefully to avoid these triggers and ensure a higher inbox placement.

December 2024 - Spamresource
Expert view

Expert from Email Geeks explains that welcome messages going to spam indicate people are signing up and reporting the mail as spam, so moving verification to an earlier step should help. Suggests telling people to look in their spam folder on the after signup page.

May 2022 - Email Geeks
Expert view

Expert from Email Geeks explains that bounces from Gmail indicate people are providing fake addresses. Non-existent ones hurt your reputation, and they likely give fake addresses that belong to someone else.

June 2024 - Email Geeks
Expert view

Expert from Word to the Wise explains the importance of maintaining a clean and engaged email list for optimal deliverability. Regularly remove inactive subscribers, hard bounces, and spam complaints. Implement double opt-in to verify email addresses and ensure genuine interest. Good list hygiene helps improve sender reputation and prevents emails from landing in the spam folder.

May 2023 - Word to the Wise
Expert view

Expert from Spamresource explains that sender reputation significantly impacts deliverability. Factors influencing sender reputation include IP address history, domain reputation, authentication (SPF, DKIM, DMARC), and engagement metrics (open rates, click-through rates, complaint rates). Building and maintaining a positive sender reputation is crucial for ensuring emails reach the inbox.

December 2023 - Spamresource

What the documentation says
4Technical articles

Welcome emails land in spam due to a combination of algorithmic filtering by email clients, authentication issues, sender reputation problems, and non-compliance with email standards. Email clients like Gmail, Yahoo!, and Outlook.com use algorithms to determine inbox placement. Authentication methods (SPF, DKIM, DMARC) are crucial for verifying sender identity. A poor sender reputation, being on blocklists, message content triggering spam filters, lack of recipient history, malware and not adhering to recognized standards all contribute to emails being marked as junk. Sending unwanted email and making it difficult to unsubscribe also lead to deliverability issues.

Key findings

  • Algorithmic Filtering: Email clients use algorithms to determine if an email should be delivered to the inbox or the junk folder.
  • Authentication Matters: Proper email authentication (SPF, DKIM, DMARC) is essential for improving deliverability and avoiding spam filters.
  • Sender Reputation is Critical: A good sender reputation is crucial for ensuring emails reach the inbox. Factors include IP address history, engagement metrics, and complaint rates.
  • Compliance with Standards: Adhering to recognized email standards helps ensure that emails are properly processed and delivered.
  • Content Triggers: Certain message content can trigger spam filters and lead to emails being marked as junk.

Key considerations

  • Authenticate Your Email: Implement SPF, DKIM, and DMARC to verify your sending domain and improve deliverability.
  • Send Only Wanted Email: Ensure that subscribers have opted-in to receive your emails and that you are sending relevant and valuable content.
  • Make it Easy to Unsubscribe: Provide a clear and easy-to-use unsubscribe link in all of your emails.
  • Monitor Your Sending Reputation: Regularly monitor your sending reputation to identify and address any issues that may be affecting deliverability.
  • Follow Sender Guidelines: Adhere to the sender guidelines provided by email clients like Gmail and Yahoo!.
  • Scan for Malware: Ensure your emails are free from malware to prevent deliverability issues.
Technical article

Documentation from RFC Editor shares technical documentation regarding email authentication standards (SPF, DKIM, DMARC) to ensure deliverability and prevent spam, highlighting the importance of proper configuration to improve sender reputation and compliance with email provider requirements.

January 2022 - RFC-Editor
Technical article

Documentation from Google Workspace shares guidance to prevent your email from being marked as spam and delivered to Gmail users: Authenticate your email with SPF, DKIM, and DMARC. Send only wanted email, make it easy to unsubscribe, monitor your sending reputation and follow Gmail's sender guidelines.

November 2022 - Google Workspace
Technical article

Documentation from SparkPost explains that if your welcome emails are being sent to the spam folder, the factors at play are: that email clients like Gmail, Yahoo!, and Outlook.com use algorithms to determine if the email should be delivered to the inbox, the junk mail folder, or blocked completely, authentication methods and the reputation of your sending IP address play a role in this.

September 2024 - SparkPost
Technical article

Documentation from Microsoft states that your email is marked as junk if you are on a blocklist, the message content triggers the junk email filter, the 'From' person is on the recipient's blocked senders list, the message doesn't use recognized standards, the message contains malware or the recipient has never contacted the sender before.

April 2021 - Microsoft