Nationwide Warntag — 11 September 2025

On Thursday, 11 September 2025 at 11:00 AM, Germany will run its annual nationwide Warntag (Federal Warning Day). The Federal Office of Civil Protection and Disaster Assistance (BBK) will trigger a coordinated test alert to verify the national warning infrastructure.

What will be tested

• Cell Broadcast (mobile phone alerts)
• Warning apps (NINA, KATWARN)
• Radio and television breaks
• Local sirens and loudspeaker announcements
• Digital information boards and social media channels

An all-clear (Entwarnung) is expected to follow at around 11:45 AM via most channels (note: Cell Broadcast may not support all-clear messages yet).

Why this matters

The exercise checks technical systems, identifies weaknesses in the warning chain, and helps familiarize the public with alert signals and procedures.

What you can do

• Enable notifications for NINA/KATWARN and test that your phone receives alerts.
• Check battery levels and notification settings on mobile devices.
• Discuss and review your household emergency plan.

Official details: BBK — Bundesweiter Warntag

Note: This is a nationwide test. If you receive the alert, it is part of the exercise.