At one point or another, you might’ve had the misfortune of stepping out of your car for a moment and, upon returning, realized that the doors have locked on you—and the key is inside.
Very little in life can be described as quite so annoying, but having a spare car key is a handy way to avoid getting locked out of your car. Keeping the spare key in the same place as the main one would be a little counterintuitive, so it’s important to know some of the more reliable ways to hide it, whether that’s on your property or elsewhere.
Read on to discover some of the clever ways you can hide primary and spare car keys without compromising the security of your vehicle.
Table of Contents
How Do Car Thieves Target Cars?
Keyless cars, or cars that use fobs or mobile apps to unlock, are at significantly higher risk of being targeted by thieves.
This is because the actual theft of the key isn’t necessary to unlock the door, and keyless thefts are becoming increasingly common as less vehicles are being manufactured with traditional key locks.
The good news, then, is that keeping spares really isn’t going to be of any increased detriment to the security of your vehicle.
What is Relay Theft?
Keyless car theft is achieved through a relay transmitter and an amplifier, generally requiring at least two people to gain access. The relay tricks the vehicle into thinking the fob is much closer to the car than it actually is by amplifying its signal.
This requires the car to be relatively close to the fob anyway, meaning that cars parked directly outside of homes are the sole target of this kind of theft.
Traditional Keys
Older cars with regular key locks, on the other hand, are made more vulnerable with the existence of multiple spares, since these are more likely to be stolen in order to facilitate vehicle theft.
If you were wondering how to hide a key in or on your car, forget about it: thieves will target cars which have keys or fobs left inside the vehicle.
In fact, an average of 209 vehicles were stolen in the US every single day precisely as a result of the keys or fobs being left inside the vehicles.
Old versus New Vehicles
As we touched upon in our article on security for cars, the increasingly valuable metals used in the manufacture of parts for newer models of cars make newer models, like hybrids, particularly attractive to thieves.
Of course, profit can be made from scrap from older vehicles, too, and a conventional forced entry (smashing the window) will be more likely if the car is already old and not especially valuable in its present state.
Not to mention, older vehicles with compromised security, like doors hanging off hinges and broken windows, are much easier to steal.
While it’s easy to imagine that parts theft is far more likely for newer vehicles, there’s no reason to assume you’re ‘safe’ from vehicle theft because of the state of your vehicle, or how desirable it’s perceived. A vulnerable, easy catch is just as likely to be targeted as an expensive vehicle.
Clever Ways to Hide Your Car Keys (And Where to Avoid)
With modern vehicles exhibiting a worrying degree of security vulnerabilities thanks to relay theft, knowing how to go about concealing and storing your car keys, be it spare or primary, is crucial in helping protect your vehicle.
Find out the best and worst places to have your car keys, including where to hide car keys in the house.
Best Places
1. Your bag/pocket
As obvious as it is, having a spare key on you at all times is among the more useful places to ‘hide’ it.
Ideally, you need to keep the primary key and the spare one separate, so if the main key were to be kept in your handbag or backpack, the spare might be kept in the pocket of your trousers or jacket.
And since fobs invite relay attacks, it’s much better to have it move around with you rather than to leave it in one place.
As annoying as it is initially, getting into the habit of having your keys separated in general is a good idea, including not keeping house keys and car keys on the same keychain.
In the event of being locked out of your car, you’ll instantly regret keeping spares and house keys on the exact same chain, and the convenience of it suddenly won’t seem so necessary.
2. In aluminum foil
Wrapping electronics up in aluminum foil is probably something you would associate with juvenile thieves stealing clothes or video games from a store. But it’s actually a tried-and-true way to reduce the capacity of wireless signals through interference.
Essentially working the same way an RFID bag does (see below), it’s a decent way to protect your fob/keyless vehicle from being opened during the night if you don’t want to part with the money for a dedicated signal blocker, particularly if your vehicle is parked in close proximity to your home.
Simply place the fob inside a small container that is wrapped in ample amounts of foil. Be very liberal with how much you use.
The metal will cause interference with signals, but it’s not nearly as reliable as a dedicated RFID bag, which is made with far denser materials that distribute electrostatic radiation. Pile on as many layers as you can, making sure not to leave significant gaps.
Bonus: Using Alfred to Protect Your Car
AlfredCamera makes a brilliant additional security measure for watching over your vehicle. Positioning an old device, or the standalone AlfredCam, out of a window to view a parked car is a common way users have been making the most of Alfred to boost car security.
‘Camera is pointed right at my vehicle – when someone slashed my tires, I was able to confront them about it and press charges.’
Incorporating vehicle security into your overall home surveillance is easy and integral to maintaining a true sense of safety, since cars are so vulnerable to being targeted.
‘I use 6 of my old smartphones to keep an eye on my home. One for my disabled wife, one for our exotic birds, one in a window to watch our cars, one in the kitchen to monitor the back door, one in the french doors to monitor our patio and one in the bathroom my wife uses in case she needs help.’
Similarly, you can use Alfred to observe specific valuables in the home, which might include keys.
Try Alfred for Android or iOS today and experience simple vehicle security at your fingertips.
3. In an RFID bag, case, or wallet
RFID, or radio frequency identification technology, is the name given to various types of wireless communication readers and trackers. There’s plenty of uses for it on the right side of the law, like tracking animals in the wild, and, more annoyingly, in car locking systems.
Most new cars use RFID for keyless/fob entry. The bad news is that this is an extraordinarily vulnerable security system: in a test of 237 vehicles, the German General Automobile Club found that 230 of them could be unlocked and started using a relay attack.
What does an RFID bag do? RFID bags (or wallets, cases, boxes, or other similar objects) are the more sophisticated version of smothering your devices in foil.
Using a Faraday cage, they block RFID signals by distributing electrostatic radiation around whatever’s inside it, so that external electromagnetic fields are blocked out.
As you might imagine, keyless fobs aren’t the only thing susceptible to attacks; credit cards, for instance, can be kept safe by being stored in a Faraday cage. So maybe it’s time to upgrade that little tray by the front door with your wallet and keys in it!
Note: Looking for RFID bags/Faraday cages? Scroll down to find some of our picks.
4. Hide-a-key
Traditional keys ultimately pose less of a security threat than buttonless fobs, so more conventional ways of hiding them can be beneficial. We’re fans of hide-a-keys, objects disguised as everyday items, like rocks, in which you can hide keys. These can then be distributed subtly around the outside of your property, depending on what object it’s attempting to look like.
Considering buying a hide-a-key? Find out what we recommend. You can also follow our simple step-by-step guide to make your own hide-a-key!
Of course, some of these can be hit and miss, and the success of it depends on how convincing and discreet the hide-a-key is. The best hide a key for cars will be made out of a durable type of plastic, so they can withstand the elements.
5. Among plants
It’s no use having a fake rock to hide your key in if the area around your property has no rocks. Placing a key among potted plants is a nifty way to get around this.
For regular keys, place them inside a small zip lock bag and insert them deep into the soil. Turn them horizontally in the soil so there’s no chance of them sticking out, and cover them with ample soil.
For fobs, you could try the same but with a small-sized RFID bag in order to block potential relay attacks. Having it both physically and electromagnetically concealed will greatly decrease the chances of falling victim to such a theft.
Worst Places
1. In your car
By far the worst place to hide keys, whether that’s a fob or a traditional key, is in your car. Between 2016 and 2018, 229,339 vehicles were stolen that had keys left inside them. Hence, it really isn’t an exaggeration to say that leaving spare keys in the car is asking for grand theft auto. Under no circumstances should you hide keys inside your vehicle.
2. On your car
License plate hide a keys can be tempting, or even just attaching the key discreetly inside the hubcap of one of your wheels can seem like a wise idea. But we’d recommend proceeding with caution if you do opt for one of these methods.
Certainly, if the key in question is a fob, don’t even think about it.
Even though it’s not nearly as convenient as having a spare on the vehicle itself, it’s much safer to have any spares around the outside of your property.
Either in soil bedding, deep within potted plants, hide-a-keys, key safes, or, for fobs, inside a RFID bag, where they will be better concealed and further away from your vehicle if a car key is uncovered.
3. Alongside other keys
Wherever you decide to keep your primary car key or hide your spare car key, it’s important to create a habit of separating all of your keys. Though keeping your keys on a single keychain or in a keycase is undeniably more convenient, losing or, worse still, having them stolen, puts your security at a very high risk.
To start with, try separating house keys (front and back door) from car keys if they aren’t already. Then try keeping spare keys and on separate keychains and in places that are decidedly far from the original cut of the key.
If you keep your original keys in your coat pockets, for instance, you could try keeping the spares in your bag, or otherwise in a hide-a-key.
Note: If you do happen to lose or have stolen a keychain, immediately replace all locks on your home, vehicles, and any other objects or places that the chain held keys for. Do not wait for the keychain to be returned to you.
Prevent Keyless Car Thefts with These Tips
Button fobs aren’t affected by relay theft
- When purchasing a car, inquire about what options you have for key systems. Occasionally, you can choose between fobs, buttonless fobs, and even smartphone apps, though physical keys are increasingly rare.
- The older type of fob, with buttons on, are not impacted by relay theft, so we’d recommend these over true keyless entries.
Keep keyless fobs on the move with you
- Intercepting the signal of a keyless fob does require it to be in relatively close proximity to the relay transmitter (e.g. if it’s inside your house, a thief can stand outside the property to capture its signal; a motion detecting security camera can notify you if it spots someone loitering).
- Keeping the fob on you, then, may actually be a more beneficial way to ‘hide’ it than to keep it in one place.
Faraday cages
- If you are hiding spares and don’t want to keep them on you, we’d strongly advise storing it in an RFID bag or case. Faraday cages, named after the scientist Michael Faraday, emerged in the 19th century when Faraday recognized that a metal cage (i.e. a conductor) being exposed to a charge only impacted the exterior of its surface.
- This is the exact same concept behind RFID bags, which you’ll sometimes see called ‘Faraday bags’.
RFID Bags and Faraday Cages
Amazon
| Hodufy Faraday Bags 9.8 x 11 Inches, Fireproof & Waterproof | TICONN Faraday Bag for Key Fob (2 Pack) | Simliang RFID & NFC Blocking Card (4 Pack) |
 Image via Amazon |  Image via Amazon |  Image via Amazon |
| ‘I was a little skeptical at first. I placed my mobile phone in the bag and asked someone to call me – nothing – it is as if my phone was not in service. Perfect.’ – Mr Warren N Keir on Amazon. | ‘I have a 2017 Honda Civic. I put the key fob in the correct pocket while sitting in the car and held the bag up to the push button start and the car wouldn’t do anything, so worked as advertised.’ – STZ on Amazon. | ‘Can’t find a problem with this blocking and it really works perfectly straight away. It’s just a plain card but it manages to transform my wallet into a contactless blocking machine. The card is the same size as a bank card and it just slots into one of the card slots in my wallet.’ – Cesar Hernandez Castaneda on Amazon. |
| From $15.79 | From $14.95 | From $8.30 |
Walmart
| Alpine Swiss Mens Genuine Leather Bifold Wallet | Viugreum Key Case | Iaowalm PU Leather Faraday Cage Protector Box |
 Image via Walmart |  Image via Walmart |  Image via Walmart |
| ‘It has EVERYTHING! RFID protection, which is key, also very soft supple leather. This held good amount of cash, all the cards, and has a flip out double-sided picture window (drivers license or ID) for ease and visibility. ‘- Quality4Me on Walmart. | ‘I have a 2017 Honda Civic. I put the key fob in the correct pocket while sitting in the car and held the bag up to the push button start and the car wouldn’t do anything, so worked as advertised.’ – STZ on Amazon. | ‘Can’t find a problem with this blocking and it really works perfectly straight away. It’s just a plain card but it manages to transform my wallet into a contactless blocking machine. The card is the same size as a bank card and it just slots into one of the card slots in my wallet.’ – Cesar Hernandez Castaneda on Amazon. |
| From $19.99 | From $9.29 | From $25.58 |
Best Buy
| Swissdigital Design Katy Rose Backpack | Samsonite Classic 2 RFID Crossbody | Nite Ize Financial Tool RFID-Blocking Wallet |
 Image via Best Buy |  Image via Best Buy |  Image via Best Buy |
| ‘This Swissdigital backpack is great! Such fine quality and so many pockets!! The big surprise was how light weight it is and comfortable to carry because it is well balanced!! I feel safe using with my wallet safely in the RFID pocket!!’ – 65NRockinit on Best Buy. | ‘Light weight with plenty of room to hold your items’ – Renee S. on Samsonite.com | ‘Great tool to have just incase. Money clip and used as multiple tools. I can’t complain.’ PEEJ37 on Best Buy. |
| From $99.99 | From $29.99 | From $15.99 |
FAQ
Where is the best place to keep car keys?
Avoiding keeping your car keys in one single place means that actually keeping them on you may be among the best places to keep them. Spares can be kept inside hide-a-key objects around your property, while fobs should be kept inside RFID/Faraday bags.
Where do you put your car keys at night?
Putting the keys near you at night, rather than the front door, is best. Keyless fobs should be placed into an RFID/Faraday box.
Does putting car keys in a tin block the signal?
Putting car keys into a regular tin will likely not block the signal, though it may interrupt it to a minimal degree. By wrapping the tin up in plenty of aluminum foil you can improve the effect. Otherwise, buy a dedicated RFID/Faraday box to store it in for total peace of mind.
What does an RFID bag do?
An RFID bag blocks radio frequency signals used by radio frequency identification devices by utilizing a Faraday cage. This stops electromagnetic fields from reaching whatever is inside the bag, therefore making it useful to protect keyless fobs, credit cards, and other objects.
Why would you wrap your car keys in foil at night?
Wrapping your car keys in foil at night mimics the effect of a Faraday cage, an object which shields whatever is inside it from electromagnetic fields. By doing this, you can prevent relay attacks, an increasingly common way to unlock and start cars by tricking the car into thinking the keyless fob is nearer than it actually is. If the keys are in foil, it may increase interference and block some of the electromagnetic waves from reaching the key, though it is not as reliable as a dedicated Faraday cage.
Are push start cars easier to steal?
Yes, push start cars are significantly easier to steal than ordinary key turn cars. Any vehicle with onboard computing is susceptible to hacking. Cars that don’t have computers in them are not. A relay attack can be used to open and start the car by tricking the car’s system into registering the key as nearer than it actually is.
Can someone steal my car without the key fob?
Yes, someone can steal your car without the key fob by using a relay transmitter and an amplifier. So long as the perpetrator is within reasonable distance of the fob (for example, outside your home), the signal can then be relayed and amplified to trick the car into detecting it as closer than it actually is.
Conclusion
One can hope that within the coming decades, car manufacturers will be able to successfully bolster keyless car security systems (and their onboard computing more generally), as they are very clearly susceptible to being unlocked and started through relay theft. And with many cars now having tablets and other smart devices built into them, there is more at stake than ever.
For the time being, following our tips and tricks on hiding and storing primary and spare car keys will help significantly reduce the risk of your vehicle being stolen.
Recommended reading:
How To Find A Stolen Car in 3 Steps
Another Car Blocking Your Driveway? | Here Is What You Should Do
How to Hide a Key (And Keep Home Invaders in the Dark)