How do I get a URN for my alarm?

You cannot apply yourself. An installer or Alarm Receiving Centre certificated by an approved inspectorate applies to your local police force on your behalf, once your system meets the required standard and is under a monitoring contract. The force issues the URN to the address, usually for a fee.

The practical route is: appoint an NSI- or SSAIB-approved installer, have the system installed or upgraded to the required standard with confirmed-activation capability, put a monitoring contract in place with a certificated ARC, and let them handle the application.

The system generally needs to be designed to reduce false alarms — in the UK that means the confirmation principles in BS 8243 — because forces will not accept systems that predictably generate unconfirmed calls.

Timescales vary by force and there is often a fee both to issue the URN and to maintain it annually. Ask your provider to itemise those police charges separately from their own, so you can see what you are paying for.

If your existing alarm was installed by a non-approved company or a previous owner, it may still be possible to bring it into scope: an approved company can inspect it, and either certify it as-is or specify what needs changing.