Short answer. The Netherlands uses two official warning channels: the public warning siren, tested on the first Monday of every month at 12:00 for 1 minute 26 seconds 1, and NL-Alert, a message sent by cell broadcast to almost all mobile phones without registration 2. If the siren sounds outside a test, go inside, close windows and doors and follow the regional public broadcaster 3.
When is the siren tested?
On the first Monday of every month at exactly 12:00, with a continuous signal lasting 1 minute 26 seconds 1. There is no test on national and religious holidays or on 4 May 1. A siren that sounds repeatedly, or at any other time, is a real alarm 3.
What should I do when the siren sounds?
The government's instruction is: "Go inside as quickly as possible. Close windows, doors and other openings" 3. Then follow the regional public broadcaster on radio or TV, and stay inside until you are told it is safe 3.
| Situation | What to do 3 |
|---|---|
| Outdoors | Go inside as quickly as possible |
| Inside | Close windows, doors and other openings |
| In a car | Park and go inside, or stay in the car with the engine off and the vents closed |
| Afterwards | Follow the regional broadcaster; stay inside until told it is safe |
Our guide on sheltering or evacuating explains the reasoning for nuclear scenarios.
What is NL-Alert?
NL-Alert is the government's alert message on mobile phones. "NL-Alerts arrive on your mobile via cell broadcast. You do not need to do anything for this" 2. It is free and anonymous and needs no sign-up 2. On basic phones, the channel is 919 2.
NL-Alert messages also appear on digital advertising screens and on public-transport information screens 4.
When is NL-Alert tested?
Twice a year, on the first Monday of June and of December, around 12:00. The next test is on 7 December 2026 4.
Are there apps?
Two official apps exist: the NL-Alert app, intended for people living near the border or who need a clearer message, and the 112NL app, for contacting 112 25. Neither replaces the cell broadcast message, which arrives without any app 2.
Which radio station should I follow?
The regional public broadcaster acts as the emergency broadcaster. Its FM and DAB frequencies, region by region, are listed on denkvooruit.nl 6. For a national crisis, the government also publishes information on Nederland veilig 5. A battery radio is on the official kit list; see also our emergency radio guide.
Frequently asked questions
Why did the siren sound on a Monday at noon?
It was probably the monthly test: the first Monday of every month at 12:00, for 1 minute 26 seconds 1.
Do I need to register for NL-Alert?
No. NL-Alert arrives by cell broadcast without registration, free and anonymously 2.
My phone did not receive the NL-Alert test. What now?
On basic phones, check channel 919 2. People near the border, or who need a clearer message, can install the NL-Alert app 2.
What if 112 does not work?
An NL-Alert will give an alternative number to call 5. See the emergency contacts page.
Sources
- Rijksoverheid — Wanneer wordt de sirene getest? — https://www.rijksoverheid.nl/vraag-en-antwoord/veiligheidsregios-en-crisisbeheersing/wanneer-wordt-de-sirene-getest (accessed 2026-10-20)
- NL-Alert (Rijksoverheid) — NL-Alert op jouw mobiel — https://www.nl-alert.nl/zo-werkt-nl-alert/nl-alert-op-jouw-mobiel (accessed 2026-10-20)
- Rijksoverheid — Wat moet ik doen als de sirene gaat? — https://www.rijksoverheid.nl/vraag-en-antwoord/veiligheidsregios-en-crisisbeheersing/wat-moet-ik-doen-als-de-sirene-gaat (accessed 2026-10-20)
- NL-Alert (Rijksoverheid) — Home | NL Alert — https://www.nl-alert.nl/ (accessed 2026-10-20)
- Rijksoverheid (Nederland veilig) — Noodnummers | Nederland veilig — https://www.nederlandveilig.nl/noodnummers (accessed 2026-10-20)
- Denk vooruit (NCTV, Rijksoverheid) — Radio — https://www.denkvooruit.nl/bereid-je-voor/zo-krijg-je-een-waarschuwing/radio (accessed 2026-10-20)
Turn this into action
Your plan for Netherlands, worked out for your household.
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- The nuclear plants and zones around your home
- Phaenyx Safe: one tap to tell your people you are safe
Sources
- Rijksoverheid · Wanneer wordt de sirene getest? checked 2026-10-20
- NL-Alert (Rijksoverheid) · NL-Alert op jouw mobiel checked 2026-10-20
- Rijksoverheid · Wat moet ik doen als de sirene gaat? checked 2026-10-20
- NL-Alert (Rijksoverheid) · Home | NL Alert checked 2026-10-20
- Rijksoverheid (Nederland veilig) · Noodnummers | Nederland veilig checked 2026-10-20
- Denk vooruit (NCTV, Rijksoverheid) · Radio checked 2026-10-20