What does RFID blocking do?
Contactless bank cards, travel cards and many ID cards hold a small chip and antenna. A reader, such as a payment terminal or ticket barrier, powers the chip with a radio field and reads it from a few centimetres away. This is RFID, short for radio-frequency identification.
An RFID blocking wallet or card stops the cards near it from answering a reader. They can only be read when you take them out to use them.
Can your cards be read without you knowing?
Yes. Contactless cards are made to answer any reader that comes close enough, and they do it silently. Card readers are cheap and easy to buy, and a phone with an NFC app can read some card details too. On a busy train, in a queue or at a bar, a reader can get within a few centimetres of your pocket or bag without you noticing.
What can be read depends on the card. On some cards it includes the long card number and expiry date. Your bank's fraud protection helps if something goes wrong, but sorting out a compromised card still takes time: a cancelled card, a new number, and every subscription and saved payment to update. Blocking stops the read from happening in the first place.
What does it block, and what not?
RFID blocking works on one frequency band. Here is what that means for the cards and tags you are likely to carry.
| Card or tag | Frequency | Blocked by BLACKOUT |
|---|---|---|
| Contactless debit and credit cards | 13.56 MHz | Blocked |
| Travel cards, such as Oyster | 13.56 MHz | Blocked |
| Most ID and access cards | 13.56 MHz | Blocked |
| Older door-entry fobs | 125 kHz | Not blocked |
| Toll tags and stock labels | 860 to 960 MHz | Not blocked |
BLACKOUT blocks ISO/IEC 14443 Type A and B cards, the standard used for contactless payment and most travel cards.
Who should use RFID blocking?
- Commuters and travellers, who spend time in crowds where a wallet is close to other people.
- Anyone who carries a work pass and bank cards together. Blocking also stops card clash at barriers, as only the card you take out gets read.
- Anyone who wants peace of mind, so a card is read only when they hand it over.
Paying by phone or watch? That works as normal with BLACKOUT in your wallet. Just keep it out of a phone case card slot.
Can you check it works?
Place BLACKOUT directly on a contactless bank card and hold them to a phone with an NFC reader app, or tap them at a till when you are paying anyway. The card should not be detected. Remove BLACKOUT and it reads as normal.
BLACKOUT RFID blocking card
Bank-card sized and 0.9mm thin. Protects every contactless card within around 5cm of it, with no battery.
Written by the AKIELO team, makers of everyday carry since 2017.
