[Action Advised] Opt-in to allow only secure TLS 1.2+ traffic in your App Engine applications

We're ending support for older TLS 1.0 and 1.1 protocols starting March 17, 2026.

MY CONSOLE   Hello jhon, We're writing to inform you of important upcoming changes regarding the Transport Layer Security (TLS) protocol versions supported by App Engine. Starting March 17, 2026, we are ending support for the older TLS 1.0 and 1.1 protocols to ensure the highest level of security for your applications and align with industry best practices. What you need to know Currently, App Engine supports HTTPS connections using TLS 1.0, 1.1, 1.2, and 1.3. However, TLS 1.0 and 1.1 are no longer recommended for use. To ensure the highest level of security, we are making the following changes: For new applications created after April 1, 2025, only secure TLS 1.2+ traffic will be allowed by default, blocking any insecure traffic. If you require TLS 1.0/1.1 for any reason, you will need to opt-out by following the guidance we have provided in the next section. For existing applications, you will have the option to opt-in to allow only TLS 1.2+ and block insecure traffic. Starting March 17, 2026, we will gradually migrate all customers to block insecure traffic. TLS 1.2 will be the minimum supported version. What you need to do For New Projects: No immediate action is required for new projects unless you require TLS 1.0 or 1.1, which will require opting out by choosing the obsolete SSL policy. Refer to the instructions for Standard or Flexible if you need to choose the obsolete SSL policy either from the Google Console or Google Cloud interface. For Existing Projects: You may opt-in to the new security settings immediately. Before you opt-in, ensure that the end users of your application have clients that are compatible with TLS 1.2. Refer to the instructions for Standard or Flexible to choose the modern SSL policy either from the Google Console or Google Cloud interface. We encourage you to opt-in within the next 90 days for a smooth transition. We're here to help We understand this change may require some planning. If you need assistance or have any questions, please contact Google Cloud Support. Thanks for choosing Google App Engine. — The Google Cloud Team DOCUMENTATION SUPPORT

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