Don’t Let Them Scan You: Blocking RFID Chips

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how to block rfid chipsEvery convenience in life comes at a cost. That’s why things are so expensive at the corner store compared to the grocery store. They aren’t selling you a carton of milk, they’re selling you a way out of a mistake in not remembering to pick up your milk early at the supermarket. That kind of convenience has a readily tangible cost – more money out of your wallet. The convenience cost of other things, such as technology, might not be so readily apparent.

Take for instance RFID chips. These are Radio Frequency IDentification chips. You’ll probably be most familiar with them by seeing them on your bank cards or credit cards. These chips are being used as a replacement for the once¬†ubiquitous¬†magnetic stripe. By using RFID on these cards instead of the stripe, the convenience we gain is that they are less susceptible to damage, and don’t need to be run through a strip reader which has its own problems. How often have you had to run a card through three or four times per transaction? It’s a pain compared to just tapping the card reader. The RFID chips can also store more information and have that information encrypted, supposedly for your safety.

Like every new technology that comes along, intended to keep us and our information safer, there are legions of people out there willing to show is that it isn’t always safe. Really though, what is 100% safe? Nothing – we just have to have an acceptable level of security and, for all intents and purposes, RFID tags are reasonably secure. Yet, they can still be surreptitiously read, decoded, and used in crimes against you.

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You may have seen videos of people using card readers bought online to brush up against a purse or wallet, thus harvesting the information from the RFID tags inside. In fact, what you see below is an RFID reader kit, called RFIDuino. Then the person takes that harvested information to their lair of evil and decrypts information to literally make copies of your bank or credit cards. At which point the Rolex shopping spree begins and you get stuck with the tab.

how to block rfid chips

It doesn’t have to be this way. The odds of it actually happening to you in the first place are extremely slim. However if you want to protect yourself a little further, there are some very easy things you can do. Remember, the R stands for Radio, so anything that louses up your music radio’s reception is going to have a similar effect on these little things. If you want to understand how RFID chips work, check out this article.

Where Did It Go?

For people who carry a wallet in the back pocket of your pants, you can easily switch to putting it in your front pocket. This has two positive outcomes. One is that it makes it harder for someone to brush up against you with a reader. Most people react very differently when getting bumped in the groin area than getting bumped on the bum. This may be enough deterrent for most would-be thieves.

The other benefit is that it’s better for your back to not have lumpy wallets ¬†throwing off the alignment of your spine when sitting. There are even commercially available front-pocket wallets with RFID blocking built in, like the one below.

how to block rfid signal

If you carry a purse or handbag, you may consider not keeping your bank cards in it, but perhaps in something that is going to be on your body where you will naturally have higher vigilance against contact. If you need to keep it in the handbag, keep it in the innermost compartment of your handbag, in a wallet. All the other stuff in your bag could create enough interference to stymie the card reader.

Keep in mind neither of these methods is a 100% foolproof. They only make the likelihood of the card being read much less.

What’s IN Your Wallet?

No, really, what is in your wallet? Is it just a leather or fabric wallet? These don’t lend much stopping power against radio waves. There are commercially available wallets that are lined with aluminum or other metallic foils that help interrupt radio waves. But you can get a similar effect by lining your wallet with foil. There are dozens of ways you can do this and dozens of sites that show you how. If you have a wallet that has a billfold slot, the easiest thing you can do is to insert a sheet of foil there. Once the wallet is closed everything inside is protected by the foil.

You could also get a similar effect by using an anti-static bag – you know the kind that some computer hardware is shipped in. Those are somewhat similar to a Faraday Cage. All the other methods are simply fancier variations on this.

What IS Your Wallet?

You can step it up a notch and find a metal container to store your cards in. Again, there are various manufactured ones specifically designed for this purpose, or you can re-use some other item for the job. The always-popular Altoids tin works. Some people also use cigarette tins for this purpose. You might even use a tin that was used to hold playing cards. All of those introduce a metal shell that helps defeat radio signals.

how to block rfid signal

Why Bother With RFID?

Couldn’t I just pry the darn thing off the card? I mean, I’ve already got the magnetic strip there, that should suffice.” Oh if only it was that easy.

The card is not your property. If you read your contract, I’m sure you’ll find that the cards remains the property of the bank or company that issued it. So you’d be damaging someone else’s property. You may find that doing so invalidates your card completely. However, you might want to call the card issuer and see if they will issue you a stripe-only card. They might or they might not. You won’t know until you ask.

What Will Work 100%?

Forgo the convenience of having a bank or credit card to pay for things and only carry cash. Of course, that introduces its own set of problems. But if you feel strongly enough about it, it’s not a bad way to go. Carrying only cash has a nice benefit of limiting what you spend to what you have on you and cuts back on impulse purchases.

The next closest thing is to have an actual Faraday Cage for your cards, not just some tinfoil. Faraday Cages are specifically designed mesh-like metal holders that essentially filter out certain electromagnetic frequencies and siphons them off to the ground. This means that you’d have to know what specific¬†frequency¬†your RFID tags operated on and have the appropriate cage for that.

You would also need a grounding strip going from the cage to the ground. It doesn’t sound very practical now does it? You’d be like one of those cars with the motion-sickness strip coming off the bumper and hitting the road. Maybe that’ll be the new fashion trend someday.

how to block rfid chips

In short, nothing will work 100% to eliminate the possibility of your RFID cards being scanned. All you can do is use or or more of the techniques above to limit the risk a little more. Also use your situational awareness. Keep an eye out for someone who just keeps bumping into people. Look for card readers that seem to have more things attached to them than they should. Don’t just hand your card over to a waiter and let them walk to the card machine with it. Treat your card like you would with cold hard cash – because it is.

I hope you feel more empowered now about the safety of your credit and debit cards. Maybe you feel ¬†a little wiser but don’t be disheartened. People are essentially good.

If you got something from this, I’d sure like to hear about it in the comments below. It’s also a great place to share any additional stories or tips that you might have. Remember, we’re all in this together.

Image Credit: Client Card Sample via WikiCommons, RFIDuino via illustir on Flickr, Altoid tin via WikiCommons, Faraday Cage via WikiCommons

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27 Comments - Write a Comment


Jeremy Garnett

I like the idea of using a cigarette tin. Best not mix them up though.


Nevzat A

Very interesting ideas, I’ve never thought it could be done :)


Scott M

I don’t like the idea of digital payments or credit cards.Cash only for me.I don’t like high interest or going into debt.


Debit cards exist and are as problematic as your credit cards. And what about your car? Keyless entry anyone?


Susana, absolutely!

Maybe I’m just an old codger, but I think we really give up a lot personal security in the name of convenience. It all comes back to personal diligence.


Netsanet G

The wallet alternative seems to be the better option.


Kevin Liske0

Oops, I accidently fried the rfid chip in the microwave. Just make sure it doesn’t get so hot that it scorches the passport/card/etc.

Guy McDowell

Depending on how the card issuer has it set up, your card might not work anymore.

I don’t recommend messing with government issued ID. No good can come from that.

You may also want to be careful not to leave items that you know have RFID chips in them near your microwave.

An NFC chip is a bit different, but I have seen an issue of Wired that had an NFC in car advertisment catch on fire sitting on top of a microwave.


Kevin, after putting the card in the microwave, are you still able to use it at the store?


Chris Marcoe

When I first learned of these, I decided I can, and have been, doing everything an RFID can without it. I’ll be doing my best not to get one in a credit card. Access to a front door, now that is a different story. I think they are a great idea for home automation.

I wonder how durable the wallets are. Opening and closing all the time. Getting sat upon. Seems like any foil would degrade faster than leather. Then you would think you are protected but you wouldn’t.

Guy McDowell

You’re probably right about any of the flexible foils.

In home building, there is a fabric that has a metallic component for insulation. I wonder if that’d do the trick. Only a Faraday Cage for the appropriate wavelengths would be perfect, so everything else is some degree of being better than nothing.



I am one of those guys that wears relatively tight pants, not ones that barely cling to my gluteus maximus. I tried carrying my wallet in a front pocket. A major OUCH. Spoke with a high voice for a couple of days.

When my last leather wallet wore out, I bought an AlumaWallet. You might have seen them advertised on late night TV. They survive submersion, being driven over by a car, etc. They are actually pretty good, although they are rather limited in their capacity. I had to winnow the cards that I do carry to about 10. That’s not 10 credit cards, that’s 10 pieces of plastic which includes my driver’s license, library card, grocery store discount cards and credit cards. After stuffing all those cards in, there is very little room for any cash. So, in actuality it is a card holder, not a wallet. However, one unplanned for benefit of the AlumaWallet is that it is RFID scanner proof.



I have had my wallet lined with a simple piece of heavy duty aluminum cooking foil for a couple of years now. I don’t know if my cards have a chip or not, but I felt better safe than sorry. I did this as soon as I found out that credit card companies and banks were going to start issueing the new cards.
Does it work? I don’t know, but how my cheaper can safety get? Couple of pennies a year for a new piece of foil if my old one tears.

Guy McDowell

It will provide a degree of protection and the price is right!

Bill Folde

Once foil is in place, how (or where) does one test to see if there is any escaping RFID signal (without purchasing a reader)?

Guy McDowell

Nice pseudonym!

Do you use the RFID chip at any store where you just have to touch it to the scanner and not insert it? That’d be the first place I’d try.

Or if you have an RFID access card or fob for work, try it in the wallet (or protective whatever) and then try it without the wallet.

Fadhli Jaffar

You can test your wallet’s security by using any smartphone with NFC. There are a handful of RFID card reader apps available. Use them to check if you can read your cards.


Fadhli, good advice! If you don’t have an NFC card to read, you might be able to get one out of a magazine advertisement. I’ve seen these a few times in magazines like Wired.


Lisa Santika Onggrid

Should I be glad or jealous that this sort of tech doesn’t exist in my country? Conventional credit card is still the way to go.

Guy McDowell

Overall? I’d be glad, but I’m also highly pro-privacy.

What country? The technology will make its way there sooner or later.

Lisa Santika Onggrid

Indonesia. Yes, it’ll be here one day. I think having known these will help me alleviating future problems as I’ll be more prepared.



Guy, you never answered the question about taking out this little chip ourselves. Will it cause the card not to work? If not, what’s stopping everyone from doing this? I think it’s a great idea, but before I take my rfid chip out I need to know if someone else did this and if their card still worked.

Guy M

I got my answer when the chip fell off my wife’s card from use. Plain worn out. I’m not sure exactly how the card provider determines this, but swiping her card no longer worked either. She was forced to get another card.

If your card provider doesn’t enforce it through technology, they will enforce it through policy.


Afia Blackwell

None of my credit cards has the RFID chip, they’re all still on the magnetic stripe, however, I have a passport and passport card and both of these have the RFID chip and you can be damn sure I want to protect those documents from electronic theft


Greg Hudson

Re the anto static bags used for hard drives etc – the theory sounds good, but has anyone actually tested it ? Chances are it WILL, but better to be 100% sure.

I have a normal wallet, and metallic pouches for the 2 cards that have chips. (eBay, $3.50 each)
Tested this morning, and with the chip inside the pouch, the supermarket scanner could not read it. Slid it out slightly so the chip was visible, and the reader read it no worries. Much cheaper than a $50 RFID wallet, more costly than some aluminum foil – but a lot tougher. Cheap insurance



Hey Greg,

Glad you shared that with us. It definitely is cheap insurance.

If a person got really industrious, they could even stitch that into the wallet, just to make it easy to get cards in and out.


Marlette Louisin

Thanks so much for the info! We’re traveling to Europe and I was recently told about the info theirs and their scanners. Both my CC have these chips and both have had unauthorized use occur in the last 12 months. One card had it happen 3x!
So, now, I’ll carry my cards, DL etc in a metal old business card case works well. Yes, it’s bigger than the usual size case.

I don’t think our passports have the chip as they’re 7 yrs old but I will be checking it out.

Thanks again
Quilting Momma

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