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Burglar alarms and home security

Burglar alarms

By Liz Ransome-Croker

Article 1 of 7

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Burglar alarms

Find out about the different types of burglar alarms you can choose from and read expert advice on how to decide which one is right for you. 

You're less likely to become a victim of burglary if you have a well-fitted and maintained burglar alarm system, according to London's Metropolitan Police and a Which? survey of ex-burglars, so it's a worthwhile investment.

The best alarm for your home depends on your personal preferences, your budget, where you live, what your home is like and what level of protection you need.

To help you make the right choice, watch our video above for a breakdown of what you need to consider when getting a burglar alarm.

Burglar alarm types

Firstly, you need to decide what you would prefer to happen when your alarm goes off:

  • Bells-only alarms make a noise, but don't contact anyone (such as the police or you). 
  • Dialler burglar alarms automatically dial the phone numbers of you or other nominated friends and family when the alarm is triggered.
  • Smart home security systems contact you or family members when the alarm goes off through a smartphone or tablet app.
  • A monitoring contract means you pay a company monthly or annually to take action or call the police if the alarm goes off. 

See below for more on these. Costs vary between the different alarm types; visit our page on burglar alarm costs to find out more about pricing and getting the best deal, including insider tips from installers. 

For ratings of big-name burglar alarm brands, such as ADT, Response and Yale, based on the experiences of 1,800 alarm owners, visit our guide to the best burglar alarm brands

Wireless alarm systems

You'll also need to choose between a wireless system or a traditional wired one.

Wireless alarms use battery-powered sensors that communicate with a control panel using radio signals. 

These alarms look nicer and are generally easier to install - you can even do it yourself. Additional sensors can be added easily, and removing the system if you move house is a lot less tricky than for those with wires. 

Wireless alarms look nicer but are more expensive.

Wireless systems tend to be more expensive, though, and you will need batteries for all components, such as the control panel and all sensors.  

Wired systems need wires running to all of the sensors to work. These systems may be cheaper to buy but are more expensive to get installed, as wires need to be hidden, so labour costs are higher. 

Find out more about the installation process, and the costs, by visiting our guide to choosing a burglar alarm installer.

Bells-only burglar alarm 

When a bells-only alarm (also called an audible alarm) is triggered, it makes a loud noise, which will hopefully alert someone in the area to the situation and/or scare off an intruder. 

However, unlike a monitored, dialler or smart alarm, it won't automatically contact a named person or the police, so there is no guarantee that anything will be done. 

Bells-only alarms won't alert you if they go off.

46% of Which? members who have a burglar alarm have a bells-only one. It's worth thinking about the kind of area you live in before deciding to get a bells-only alarm. 

Is there an active neighbourhood watch giving you confidence that someone will call the police? Or perhaps you have friends and relatives who live very close by who you could count on to take action?

You can install one of these alarms yourself, or you can pay a one-off fee to have it installed by a professional. 


  • You won't have to pay for a monitoring contract (read more on these below).
  • Having an alarm, no matter what type, can help to deter a burglar.
  • You can install it yourself.


  • You won't be alerted when your alarm goes off unless someone nearby hears it and knows how to contact you.
  • Without anyone to stop a break in, the alarm on its own may not deter burglars.

We've spoken to ex-burglars to find out what security measures are more likely to stop your home being broken into. Read Do burglar alarms and CCTV work? to find out. 

Dialler burglar alarm

If you're not comfortable with the idea of relying on a neighbour to let you know if your alarm goes off, you could consider a dialler alarm, also called an auto dialler. 

With these alarms, the dialler will contact you or nominated friends and family when it goes off. This means that you or they can then contact the police or a neighbour with a key to investigate the issue.

A dialler alarm will contact you or nominated friends and family if the alarm is triggered.

Most diallers allow you to programme in between three and 10 numbers to be called, which will be dialled in the priority order you've set. The first person it successfully contacts will be able to stop the rest of the numbers being contacted.

You can also buy models that will alert you if there is a fire or flood in your home or that connect to a panic button. 

There are two types of dialler alarm:

  • Speech diallers use your phone line to call the numbers you have assigned. This means you'll need to have a landline and wires running from it to the alarm.
  • GSM diallers use mobile network signals, so you won't need a phone line. There will also be no need to run wires. But you'll have to buy a Sim card and make sure it's topped up with credit to make the necessary contacts when needed. You'll also need to be wary about mobile signal - check that it's strong where you live before you go ahead.
  • You won't have to pay for a monitoring contract.
  • You or the people you've nominated will be alerted when there is an intruder.
  • If you buy one with additional detectors, you can also be warned about other dangers, such as fires.


  • You or your nominated contact(s) might all be unavailable when alerted, unless you choose a model that will allow you to programme in a lot of numbers.
  • If you choose a GSM dialler, a weak mobile network signal will affect how well it works.
  • If you get a speech dialler, you'll need a landline and will have extra wiring in your home.

Smart home security systems

Smart home security systems connect to your smartphone or tablet, or those of family members. This enables you, or them, to be alerted when your alarm is triggered, as with a dialler alarm. They also allow you to control your smart security from your phone, even when you're away from home. 

There are a lot of different options when it comes to smart home security. In all cases, you will need a central hub that then connects all other compatible devices to it via wi-fi - a little bit like a standard wireless alarm connects to sensors. 

You can then connect a number of elements to it, depending on the system you choose, including motion senors, cameras, or even sockets that allow you to switch your lighting on and off when you're out.

You can install a smart system yourself, but be aware that you might not place all of the items in the best possible position. 

Smart systems can also be expensive, especially if you want or need to keep adding components to it. For example, a basic kit costing around £200 might only come with the main hub and a few sensors. It's likely you'll need more to cover your entire house.

We've tried out a number of smart home security systems to see how easy they are to set up and use, and asked a security expert to asses how likely they are to deter an intruder.

You can also visit our guide to smart home automation to find out what other smart security gadgets are available, including door locks and security lights.


  • It will alert you when you're away from home.
  • It can be monitored and controlled from your smartphone.
  • You can set up a smart system yourself.


  • Not all smart security systems will be a deterrent - it depends what components you get and where you place them.
  • As with a GSM dialler, whether or not you're alerted depends on your mobile network signal.
  • They can be expensive.

Burglar alarm monitoring contracts

If you want even more peace of mind that any problem at your home will be dealt with, you could consider getting a burglar alarm with a monitoring contract. 

You can get a monitoring contract for a wired or wireless alarm, but both the alarm itself and the installation need to conform to certain standards - you won't be able to install it yourself. 

There are two types of monitoring contract: keyholder and police response. With both types, you pay extra per month or annually to have your alarm system monitored, which means the nominated keyholder or the police will be alerted when the alarm goes off - 17% of Which? members with an alarm have a monitoring contract.

The idea is that the alarm system connects to a receiving centre that is notified each time your alarm is triggered. The receiving centre will first of all call your home landline asking for your password identification. If this is incorrect or no one answers, it will take action, inform the keyholder(s), or call the police, depending on what type of contract you have.

Keyholder monitoring

Keyholder monitoring is done through a company (the 'receiving centre'), which will either respond itself when the alarm is triggered, or contact your nominated keyholders. These companies usually also offer maintenance contracts and can remotely check for problems - just make sure you get a breakdown of any extra costs this could incur before committing to buy.

Nominated keyholders must live within 20 minutes of the house, be able to drive and have access to the house. It's your responsibility to keep the alarm company up to date with their details, and suggest alternatives if they are away. 

A number of installers we spoke to didn't believe that monitoring contracts with nominated keyholders is any better than having a dialler, especially as there's an annual cost involved. However, the 24-hour service offered by monitoring, as well as knowing there is a dedicated company that is liable if action isn't taken, may make you feel more secure.


  • Some companies also offer alarm maintenance.
  • A dedicated company is on hand to take action if there is a problem at your home, and are liable if it doesn't.


  • It costs money each month or year.
  • You cannot install them yourself.
  • Keyholders must live close to your home, and you'll need to keep your contact list up to date.

You can read more about what burglar alarm installers recommended to us, as well as how their advice varied, on our burglar alarm and installation page.

Police monitoring

In addition to a receiving centre being made aware that your alarm is going off, this type of contract means the police will also be contacted by the receiving centre. If you would like this kind of contract, it's important to check that the company is registered with the local police force. 

When your alarm goes off, two indicators within the house, such as a door contact and a motion sensor, must both have been triggered to warrant police call-out. This is to avoid false alarms wasting police time. 

The Metropolitan Police says that a massive 92% of all alarm activations nationally in recent years have been false alarms. If your system has three false alarms (four in Scotland) in 12 months, you’re struck off the police register, and they won’t respond if the alarm goes off. 

It's worth noting that paying for this service won't guarantee the police will come out. One police officer we spoke to, DCI Taylor, said that whether police go to your home - and how quickly - depends on what other incidents are happening and what other resources are available. He said: ‘If we’re fairly certain there’s someone in the premises, it’s a higher priority.’


  • The police will be automatically contacted if your alarm goes off.
  • Some companies also offer alarm maintenance.


  • It costs money monthly or annually.
  • You can't install them yourself.
  • There is no absolute guarantee that the police will go to your home.
  • If you have a number of false alarms, the police won't respond to any call-outs.

Maintaining your burglar alarm 

With any standard burglar alarm, regular maintenance should highlight and reduce defects, give you peace of mind and give you more redress if something goes wrong - 35% of Which? members with a burglar alarm have their alarm maintained.

If you get a burglar alarm maintenance contract, your alarm will be checked once a year (twice a year if you have a police-monitoring contract) either by an installer coming to your home, or remotely by the company contracted to do so. 

Costs for this vary, particularly as you can get different levels of maintenance, such as additional free call-outs or parts included. Our page on burglar alarm costs details what we found when we called a number of different installers, and gives you tips on how to get the best deal. 

Having your alarm system professionally maintained can help tackle any problems with false alarms. It is also a requirement of some insurance companies, and a requirement if you have a monitoring contract.