8 Signs That Your House Is Marked for Burglary

May 29 2025

Burglars will employ a variety of tactics to try and enter homes. Yes, burglary is often random and opportunistic, and you can use a whole host of different tactics to prevent it, but increasing organised crime means that having your home targeted in advance is a growing concern.

Whether they’re impersonating a salesperson or observing the comings and goings at a particular house, intruders rely on deception and vulnerability to gain access.

Join us as we take you through some of the telltale signs that your home is ‘marked’ for burglary, and what to do about it if you’re suspicious, or feeling unnerved.

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Graffiti or chalk symbols: Intruders mark properties with symbols that signify a range of meanings, like if the house is alarmed.
Unfamiliar vehicles parked nearby: Keep an eye out for any suspicious vehicles parked on your street.
Broken locks or outdoor lights: Check for any tampered-with locks or broken lights.
Evidence of trespassing: Footprints or unusual items left in your garden could mean someone has tried to enter your property.
Increase in door-to-door activities: Unfamiliar or pushy salespeople, solicitors, or engineers trying to enter your property without ID.
Stolen dogs: Noisy, protective animals can draw attention to intruders, so a missing dog could indicate future criminal activity.
Increase in local break-ins: Stay up to date with local crime rates.
Unidentified vans: No markings or advertising could mean a van is trying to scope your property.

1. Graffiti or chalk symbols

A tactic you might not be aware of is what burglars call ‘marking’. With graffiti spray paint or chalk, they leave symbols around the outside of your property, such as on a wall or on the pavement. Each symbol has its own meaning too, including whether or not the house has an alarm, information about valuables inside a home, and if the property has been targeted before. It’s linked to gang crime and allows criminals to subtly communicate with each other without getting caught.

2. Unfamiliar vehicles parked nearby

Be sure to keep an eye out for any unfamiliar vehicles loitering outside your property. While on most occasions it might be a neighbour’s friend or a construction worker, there’s still a possibility it could be a burglar targeting your home, or another house on your street. If you’re unsure, double check with your neighbours to see if they can identify them.

3. Broken locks or outdoor lights

Broken or tampered-with locks is another sign burglars might be targeting your home. If you notice your locks are damaged or altered, be sure to repair or replace them as soon as possible. Typically, burglars will return at a later point to try and finish the job they started.

What’s more, intruders might damage outside lights to remain inconspicuous. As a result, you might find wirings cut off or lighting structures broken, allowing them to hide their identity, making it easier for them to go in and out of your home unseen.

4. Evidence of trespassing

Notice any unusual footprints? Perhaps you’ve found strange items left in your garden that don’t belong to you? This could be evidence that your home is being monitored by intruders. If something doesn’t feel right, be sure to report it to the local authorities.

5. Increase in door-to-door activities

Another common tactic used by criminals is to impersonate a salesperson, solicitor, or engineer to enter your home. Look out for people frequently walking past or asking unusual questions, and always be on high-alert when dealing with unfamiliar faces at your door. Burglars can use this method to identify entry points in your home and check if there are any valuables to steal.

We recommend answering the door with your chain in place if you aren’t expecting a call, and requesting ID before you let anyone in.

6. Missing dog

As you might know, dogs can be an effective deterrent for burglars. Loud, intimidating, and protective, they draw attention to suspicious activity, making it harder for intruders to get away with their crimes unnoticed. That’s why a burglar could target your dog to avoid getting caught. If your pet goes missing under unusual circumstances, make sure you stay alert.

Consider having your furry friend microchipped and ensure the registration details are up to date. This gives you the best chance of being reunited with your pet as soon as possible, should they ever be stolen.

7. Increase in local break-ins

A rise in break-ins or criminal activity in your neighbourhood could mean your home’s at risk. Keep up to date with local crime reports, work with neighbours, and always report suspicious activity to the police to ensure your property isn’t next.

If you’re moving homes and crime rate is high on your list of concerns, explore our Crime in My Area tool.

8. Unidentified vans

In an attempt to monitor your home without drawing any attention, burglars use vans with no advertising or company logo. If you see a van parked nearby for extended periods of time or returning at strange times, it could signify someone is scoping out your property. Stay vigilant and report any suspicious activity to local authorities.

What to do if you believe your home is marked

Contact the police. They’ll be able to investigate, log your complaint and advise you on what to do next.
Increase your preventative measures. Hide valuables, remove any emergency keys from outside your home and look into extra bolts and chains for your entry points.
Upgrade your home security system. Burglar alarms and cameras can be effective crime deterrents in themselves but can also alert you or even the police immediately in the event of any suspicious activity.

At ADT, we’re serious about helping you feel safe. From next-generation home security systems tailored to your needs, to a Smart Home hub that allows you to control your unique solution from your phone. Get in touch with one of our security experts for your free quote.