Can NFC tags be read through metal surfaces?
Standard NFC tags cannot be read through metal surfaces — metal absorbs the radio frequency signal. Specialized 'on-metal' NFC tags include a ferrite shield layer that redirects the signal and work when attached directly to metal surfaces.
Why metal blocks NFC
NFC operates by inductive coupling — the phone emits a changing magnetic field that induces current in the tag's antenna coil. Metal surfaces absorb this magnetic field (eddy currents). An NFC tag placed directly on metal (like a laptop or a metal card holder) will read unreliably or not at all.
On-metal NFC tags and cards
Products designed for metal use (on-metal stickers, metal NFC business cards) include a layer of ferrite material between the chip and the metal surface. Ferrite redirects the magnetic field rather than absorbing it, restoring normal read distance. Metal NFC business cards are typically designed this way — the card can be placed on a metal desk surface without blocking the chip.
Will a metal business card holder block my NFC card?
Possibly. If the card is sitting flat in a solid metal case, reads may be unreliable. Most card holders aren't thick solid metal, so reads usually still work when the card is pulled out slightly.
Can NFC be read through a metal wallet?
No — a solid metal Faraday wallet blocks all RF signals, including NFC. This is actually the point of those wallets: to prevent card skimming.
Can the phone's NFC signal be blocked by other cards?
Credit cards and transit cards in the same area as the NFC business card generally don't prevent a read, though having many NFC/RFID cards in a wallet can occasionally cause interference. Isolating the NFC business card removes this issue.