Summary
Gmail rejects unauthenticated emails from @gmail.com when sent via SendGrid due to DMARC policy enforcement. This is because DMARC, along with SPF and DKIM, authenticates email senders and prevents spoofing. For DMARC to pass, the 'From' address domain must align with the domain used for SPF or DKIM. Since SendGrid is not authorized to send on behalf of Gmail, emails using a 'gmail.com' 'From' address will fail DMARC checks, resulting in rejection. Sending from a freemail domain for bulk mail is generally a bad idea. The best practice is to use a domain you own and properly authenticate it with SPF, DKIM, and DMARC to ensure your emails are delivered successfully.
Key findings
- DMARC Enforcement: Gmail actively enforces DMARC policies to protect against email spoofing and phishing.
- Authentication Failure: Sending emails from '@gmail.com' via SendGrid fails DMARC checks due to a lack of SPF and DKIM alignment.
- Domain Alignment: DMARC requires that the domain in the 'From' address aligns with the SPF or DKIM authenticated domain.
- Freemail Issues: Using free email domains for bulk mail is a bad practice and may lead to deliverability problems.
Key considerations
- Domain Ownership: Use a domain you own and control for sending emails.
- Authentication Protocols: Properly configure SPF, DKIM, and DMARC for your domain to authenticate your emails.
- Avoid Spoofing: Avoid using 'From' addresses that you are not authorized to send from, as it leads to DMARC failures and rejection.
- DMARC Compliance: Comply with DMARC requirements to ensure your emails are delivered successfully and to protect your domain from spoofing.
What email marketers say
12 marketer opinions
Gmail rejects unauthenticated emails from @gmail.com sent via SendGrid due to its enforcement of DMARC policies. DMARC, along with SPF and DKIM, are email authentication methods designed to prevent spoofing. When sending emails from SendGrid while using a 'From' address of '@gmail.com', the email fails DMARC checks because SendGrid is not authorized to send on behalf of Gmail. This lack of alignment between the 'From' domain and the sending source triggers Gmail's DMARC policy, resulting in rejection. To avoid this, senders should use a domain they own and properly authenticate it using SPF, DKIM, and DMARC, ensuring that these protocols align with the 'From' address.
Key opinions
- DMARC Enforcement: Gmail actively enforces DMARC policies to protect users from spoofing and phishing.
- Authentication Failure: Sending emails from '@gmail.com' via SendGrid fails DMARC checks due to lack of SPF/DKIM alignment.
- Domain Ownership: Using a domain you own and properly authenticating it is crucial for passing DMARC checks.
- Spoofing Prevention: DMARC is designed to prevent unauthorized use of domains and protect against email spoofing.
Key considerations
- Domain Authentication: Implement SPF, DKIM, and DMARC records for your sending domain to establish trust with email providers.
- Alignment Checks: Ensure that SPF and DKIM align with the 'From' address domain to pass DMARC authentication.
- Sender Reputation: Failing DMARC checks can negatively impact your sender reputation and email deliverability.
- Avoid Spoofing: Refrain from using 'From' addresses that you are not authorized to send from to prevent DMARC failures and potential rejection.
Marketer view
Marketer from Email Geeks explains that long before DMARC, DKIM, or SPF, it was possible and sometimes advisable for domains to reject “internal” mail from external sources. He suggests that Gmail's policy might be to reject inbound mail using gmail.com in the From: domain if it doesn't pass DMARC validation.
6 Sep 2021 - Email Geeks
Marketer view
Email marketer from Reddit explains that for DMARC to pass, either SPF or DKIM must align with the 'From' address. If you're sending from Sendgrid but using a 'gmail.com' From address, neither SPF nor DKIM will align, causing DMARC to fail and Gmail to reject the email.
29 Dec 2022 - Reddit
What the experts say
3 expert opinions
Gmail rejects unauthenticated emails claiming to be from @gmail.com when sent through SendGrid due to strict DMARC enforcement. Using free email domains like Gmail for bulk mail is generally discouraged, as it's often seen as a spam indicator. DMARC is specifically designed to prevent unauthorized use of a domain by instructing receiving mail servers on how to handle emails that fail authentication checks (SPF and DKIM). Gmail actively enforces its DMARC policy, rejecting emails that appear to originate from Gmail but aren't properly authenticated by Gmail itself.
Key opinions
- FreeMail Bad for Bulk: Using free email domains for bulk sending is a bad practice.
- DMARC Enforcement: Gmail aggressively enforces DMARC to prevent domain spoofing.
- DMARC Function: DMARC is designed to prevent unauthorized use of a domain by providing instructions to receiving servers.
Key considerations
- Authentication: Ensure your emails pass SPF and DKIM checks to avoid DMARC failure.
- Domain Control: Use a domain you control for sending emails and authenticate it correctly.
- Bulk Mail Practices: Avoid using free email domains for sending bulk emails.
Expert view
Expert from Email Geeks states it's generally a bad idea to use a freemail domain for bulk mail, considering it a spam sign. She advises buying a domain and configuring it for commercial bulk mail.
1 Feb 2022 - Email Geeks
Expert view
Expert from Spam Resource (John Levine) explains that Gmail is aggressively enforcing DMARC policies, especially regarding emails claiming to be from gmail.com but originating from other sources. Sending from SendGrid using a gmail.com 'From' address fails DMARC checks because SendGrid isn't authorized to send on behalf of Gmail, resulting in rejection.
11 Dec 2024 - Spam Resource
What the documentation says
5 technical articles
Gmail rejects unauthenticated emails from @gmail.com sent via SendGrid because of DMARC policies designed to prevent email spoofing and phishing. DMARC instructs receiving servers how to handle emails claiming to be from a specific domain that fail SPF and DKIM authentication checks. For DMARC to pass, the 'From' address domain must align with the domain used for SPF or DKIM. Sending from SendGrid with a @gmail.com 'From' address will fail because SendGrid isn't authorized to send on behalf of Gmail. This aligns with the DMARC specification (RFC 7489), where email receivers should handle messages that fail authentication.
Key findings
- DMARC Purpose: DMARC prevents email spoofing by allowing domain owners to specify how unauthenticated emails from their domain should be handled.
- Alignment Requirement: DMARC requires the 'From' address domain to align with the SPF or DKIM authenticated domain.
- Gmail Compliance: Gmail adheres to the DMARC specification (RFC 7489) by rejecting unauthenticated emails from gmail.com sent via third-party services.
- SPF Purpose: SPF records help prevent email forging.
Key considerations
- Authentication Setup: Configure SPF and DKIM records to properly authenticate your domain for email sending.
- Domain Authorization: Only send emails from domains you are authorized to send from.
- DMARC Policy: Understand and implement a DMARC policy to protect your domain from email spoofing.
- SPF Record Setup: Configure SPF records to specify which hosts are allowed to send from your domain.
Technical article
Documentation from Google Workspace Admin Help explains that if an email claims to be from your domain but doesn't pass SPF or DKIM checks, DMARC tells receiving servers what to do with it. Gmail may reject these emails if your DMARC policy is set to 'reject' or if it identifies the email as suspicious.
9 May 2025 - Google Workspace Admin Help
Technical article
Documentation from DMARC.org explains that DMARC helps prevent email spoofing by allowing domain owners to specify how receiving mail servers should handle unauthenticated emails that appear to be from their domain. Gmail is likely rejecting the emails to protect its users from phishing and spam.
5 Oct 2024 - DMARC.org
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