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How can I physically modify my credit card such that it is no longer possible to communicate wirelessly?

My bank sent me a new credit card with tap-to-pay functionality. I told them I don't want it; they said tap-to-pay is being forced by Visa, and all old cards without wireless payment (even if not expired) have a hard-cutoff for deactivation by Visa.

99.9% of the time I only use my card for online payments (I always prefer to pay with cash or crypto). But I do carry it with me as a backup just-in-case. My wallet doesn't have wireless shielding, and I don't want to worry about theft. I know the risks of theft are low, but I also know the risks are lower if this "feature" is deactivated.

How can I physically cut into my new tap-to-pay visa card such that it is no longer capable of making wireless payments?

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    "I don't want to worry about theft." Good news: You don't have to. There are no indications this sort of theft is occuring in any significant numbers; credit card skimmers are a far greater threat, one you'd be exposing yourself to by forgoing contactless payments. Contactless is vastly safer. The fear of RFID skimming is largely generated by RFID wallet manufacturers.
    – ceejayoz
    Oct 17, 2022 at 17:13
  • Key being "significant numbers" As I said, I prefer not to use my card at all. But I do carry it with me. If I use my card once every 2 years, but I carry it with me every day, then the risk of having my card stolen wirelessly is higher than from a card skimmer. Oct 17, 2022 at 17:21
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    @qualityfreckle it cannot be "stolen" wirelessly. That's not how this works, that's not how any of this works. Even if it is, even though it is much likely to be stolen through your online shopping than "wirelessly" or even through a skimmer, the anti-fraud protections would kick in and hold you harmless.
    – littleadv
    Oct 18, 2022 at 17:54

4 Answers 4

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This answer does not address the legality of cutting into a credit card, and I haven't tried it myself. Results are not guaranteed.

Generally speaking, if you make any cut through the antenna it will completely disable the antenna. The antenna should be a pretty big loop of wire that probably goes near the outside of the card, but not too near. So, you might try cutting off a corner or cutting into an edge to see if the wireless feature stops working. The exact pattern will depend on who manufactured your card - you can Google it to see some patterns.

Do not cut near the chip (metal contacts) or the magnetic strip as it may prevent the card working in chip mode or magnetic strip mode.

You cannot just remove the tap-to-pay chip, since it's usually the same chip that makes the card work when inserted into the chip slot. Having only one chip that does both saves money.


The antenna consists of a long loop of wire (several turns), connected to the chip at both ends. When brought near a reader, the reader emits an alternating magnetic field that induces a current in the antenna. If you cut the loop anywhere, the current can't flow since it needs to flow through the entire loop. This is different from e.g. a car antenna, which is only connected at one end and can still receive some signals if you cut it halfway.

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  • Are you sure that if you snip-off the last 0.5 mm of the antenna, it will completely disable the antenna? I would expect that would just make the range of the antenna very slightly reduced Oct 17, 2022 at 19:14
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    NFC "antennas" are coils. Break the coil and they stop working. Oct 17, 2022 at 20:01
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    @qualityfreckle see this link or this one for a couple case study references (with instructions on how to do it) for what this answer is describing. Have not found a scientific one but it seems to me from googling around that if the antenna is missing or broken, the card will not function for contactless at all.
    – Flats
    Oct 18, 2022 at 17:48
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    I think it would be better to describe it as an "induction coil" rather than antenna, because that's what it is. Shortening the antenna doesn't necessarily prevent the transmission from going out, but cutting the induction coil cuts the power off from the transmitter.
    – littleadv
    Oct 18, 2022 at 17:58
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    @littleadv one way to view the loop is as a "small loop antennas". Cutting a small loop antenna stops it from working properly since it relies on the same current flowing through the whole loop. The loop is too small to act as a regular open-ended antenna.
    – user253751
    Oct 18, 2022 at 18:27
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But I do carry it with me as a backup just-in-case. My wallet doesn't have wireless shielding, and I don't want to worry about theft. I know the risks of theft are low, but I also know the risks are lower if this "feature" is deactivated.

  1. If someone steals your card and then has it in their possession, disabling the feature doesn't help, since they can still swipe it or read the numbers off the card.
  2. Yes, it's possible for a thief to brush up against you and tap your pocket without stealing your card, but right now that's probably much less likely than just stealing the card as described in #1. See Flats' answer for an inexpensive solution to this problem if it's keeping you up at night.
  3. Perhaps one of the greatest benefits of Credit Cards is that you actually don't have to worry. If your card number is compromised, you are just a phone call (or chat or mobile app) away from having it disabled and a new one sent to you, and you won't be liable for any of the fraudulent charges. Although annoying when it happens, this should be enough reassurance to not "worry" about it.

Side Note: I highly recommend setting up automated alerts so you can be made aware of any suspicious usage within seconds. This might also help prevent you from feeling the need to check your card usage every 5 minutes after someone brushes up against you on the subway, etc. 😉

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  • "you...don't have to worry. If your card number is compromised, you are just a phone call...away from having it disabled" there's a very big stipulation here. You generally have to report the card as having been lost/stolen within some months. But if you only check-up on your accounts once per year, then the chances are quite high that you'll be liable for any charges made by thieves. It's much less risky to completely eliminate a vector of attack (if you don't need that risky "convenience" feature) than to hope you can detect it in-time. Oct 17, 2022 at 19:08
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    @qualityfreckle Fair enough. In that case my Side Note should be very helpful for you. ;)
    – TTT
    Oct 17, 2022 at 19:38
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    @qualityfreckle if you only check your account once a year for a card that you routinely use over the internet - wireless skimming is the least of your risks.
    – littleadv
    Oct 18, 2022 at 17:55
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Not exactly the answer you're looking for I'd imagine, but if I were you I would simply get a wallet that does have the shielding you mention. Simplest solution that doesn't involve altering the card in anyway and risking potential damages.

You could also purchase RFID blocking sleeves for your card, Amazon sells them for about $5 for 10 sleeves.

If you really don't want to buy anything, then you can simply use some aluminum foil from the pantry, and create your own sleeve out of that. Perhaps make a sleeve out of cardboard and tape, line it with foil on the outside, then place the card in-between. The foil will block the signals just as well as any of the ready-to-go solutions on Amazon or in a new wallet, but it might not look the flashiest.

See here or here for some links to instruction on physical card alteration like is being described in @user253751's answer

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My bank allows me to control the functions that my Visa Card can perform:

Visa Card switches

If your bank doesn't allow that, find yourself a better bank.

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    Worth calling out: This prevents the card from being used for these types of transactions, but doesn't make the card itself behave any differently. If the concern is data being accessed on the card by someone bringing a reader near it, these settings won't help, but if the concern is someone performing a relay attack, it ought to block it.
    – Bobson
    Oct 19, 2022 at 13:31
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    @Bobson To be more precise about "data being accessed": Some contactless cards use the same account number and cardholder name on the contactless part as the contact/printed part. This poses a privacy and fraud concern. Some other contactless cards (AMEX in particular) use a different contactless-only PAN and a generic name, so it becomes more of a relay attack and generic tracking concern.
    – user71659
    Oct 19, 2022 at 23:12
  • This solution absolutely does not work. The card will still wirelessly transmit its private keys to anyone who scans it (eg walking on a public street). I just tested a visa card issued this year (2022) by tapping it to my phone with NFC enabled and a fresh install of the NFSee app (from F-Droid), and I was horrified to see that my credit card number and expiry were sent to my phone. That's two out of three private keys needed for CNP transactions. The last is just a 3-digit number that you can't change. f-droid.org/en/packages/im.nfc.nfsee Dec 28, 2022 at 16:17
  • Granted, an attacker with the right tools might be able to access some identifying data from a credit card. They might also read the RFID tag still attached to my winter jacket, and they could probably read the ID chip implanted behind the ear of my son's cat. But all of those 3 bits of information are useless for completing a payment if the credit card provider has switched off payment processing for that particular account. It seemed to me that the OP was mainly concerned about preventing payments / preventing theft, and that's what my answer addressed. Dec 29, 2022 at 0:56

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