Gmail, an essential tool for accessing inboxes, is preparing to significantly tighten its requirements for senders. Starting November 2025, Google will introduce modernized controls and increased transparency during rejections. For businesses and digital professionals, these changes mark a turning point where mastering technical standards becomes essential to ensure email deliverability and protect brand reputation.
Stricter sending rules to secure exchanges
The effectiveness of anti-spam filters relies on protocols like SPF, DKIM, and DMARC, which are crucial for verifying the identity of senders. However, many organizations are slow to adopt these standards or operate with incomplete configurations. In response to the surge of non-compliant or fraudulent emails, Gmail now imposes uncompromising rigor.
Once the new measures are implemented at the end of 2025, each message will be subject to a rigorous analysis at the SMTP level. Any flaw in authentication, whether it involves SPF, DKIM signature validity, or the absence of an aligned DMARC policy, will result in an explicit refusal rather than merely being classified as spam. This change requires a thorough review of sending practices and ensures the robustness of DNS settings.
The new bounce codes introduced by Gmail
One of the major developments is the introduction of standardized error messages for blockages. Each technical incident detected will translate into a specific bounce code, sent by the recipient server, thereby facilitating diagnosis:
- 4.7.26: sending rate limited due to missing complete authentication (SPF or DKIM absent)
- 4.7.27: error related to an SPF issue
- 4.7.30: DKIM deemed invalid
- 4.7.31: complete absence of a DMARC policy
- 4.7.32: domain mismatch (poor SPF/DKIM/DMARC alignment)
Other codes are likely to emerge as developments occur, each aiming to precisely identify the flaw and limit its impact on the sender’s reputation.
This new granularity allows for quickly pinpointing the source of problems and adjusting configurations without unnecessary trial and error, enhancing the overall security of exchanges.
An added value for all users
While these alerts may seem constraining, they primarily offer immediate traceability in the event of a send failure. Unlike a silent redirection to the spam folder, the sender now receives a clear notification identifying the exact technical issue.
This direct access to the error promotes increased responsiveness and better transparency in campaign management. Users thus benefit from an inbox that is less exposed to risks, gaining in trust and quality of experience daily.
Concrete consequences for email marketing
Strengthened controls directly impact email marketing professionals. A lax policy can now abruptly exclude entire flows of legitimate newsletters or promotional offers. It is no longer a question of if, but when technical infrastructure must be upgraded, or risk seeing a decline in deliverability statistics, especially during peak commercial periods like Black Friday.
Faced with this growing complexity, many specialized platforms offer to delegate the centralized management of DNS, cryptographic signatures, and validation settings. This outsourcing aims to ensure consistency between domain name, sending system, and displayed identity with all providers, including Gmail. At a large scale, these adjustments become crucial for preserving brand reputation and ensuring campaign performance.
Anticipate and adapt calmly
The first step is to regularly audit configurations: check the alignment between SPF, DKIM, and DMARC, and ensure that the declared policy meets current requirements.
- Ensure that each domain has a valid and up-to-date SPF record
- Make sure an operational DKIM key signs all outgoing messages
- Implement an explicit DMARC policy, favoring strict application over mere reporting
Analyzing automatically generated DMARC reports allows for enhancing security and proactively detecting potential misuse. Specialists also recommend monitoring sending volumes, avoiding abnormal fluctuations, and regularly cleaning up contact lists to remove inactive or risky addresses.
These best practices form the foundation of successful adaptation to the new constraints imposed by Gmail and, more broadly, by the entire sector.
Towards collective accountability in the sector
While large groups react quickly, the widespread adoption of these requirements will elevate the entire market, including SMEs and associations. Collaboration between IT teams, email service providers, and communication agencies becomes essential to remain compliant and effective.
Automation is gaining ground, with tools capable of continuously monitoring technical compliance, the occurrence of SMTP incidents, and sensitive periods. This dynamic helps to establish lasting trust in digital channels and to counter increasingly sophisticated fraud attempts.
Making visible what was invisible
Until now, a large portion of poorly configured messages were silently relegated to the spam folder, complicating the tracking of anomalies for senders. Now, with the policy initiated by Gmail, each incident takes the form of an exploitable diagnosis, profoundly transforming the professional culture of email.
The demand for alignment and clarity encourages moving away from the old opacity. Understanding the journey of an email, from sending to delivery or rejection, is becoming accessible to everyone — an advancement that already foretells other shifts towards a more secure and efficient messaging environment.
