I have an RFID-enabled ID card for work that is used for building access. While I can use a lanyard, cord-reel, etc. to carry the card and still have convenient access to it, I'd like to simply put it between my phone and its case. (I have legitimate reasons for this that are tangential to the question.)
My concern is that I already have a small metal plate in there that I use to hold the phone to a magnetic mount when I'm in the car. The plate itself is of no concern to me – it's just a small piece of ferrous metal and does not impact the functioning of the RFID chip.
My question is: will the regular very close proximity (1-2mm) of the strong magnets in the car mount cause any issues with the functioning of the RFID tag in the card? It would be exposed for about an hour 2x per day, plus other random trips.
My guess is that it would not be impacted any more than the solid state circuitry in the phone itself, but I'd like to get confirmation.
Additional notes: You now know as much about the particular RFID chip in my card as I do. You also know as much about the magnets in the mount as I do. Unfortunately, I can't provide any more specifics than this because I don't know them.
UPDATE: For those who may come across this question in the future – I thought I'd come back to mention that I've been using the RFID card in the phone case since I asked this question and I've never had any issues. All the "it will have no effect" answers were, in fact, correct. At least for my particular card.
Best Answer
The magnetic field from a magnet is static. In order to induce a current and/or voltage you need a changing electro/magnetic field.
Typically the field that RFID uses for operation has a frequency of at least 120 kHz but typically 13.56 MHz. That's much faster than you can practically generate by physically moving the RFID card around a magnet.
So near a permanent magnet you would be inducing a field but with a much lower frequency. The RFID tags are much less sensitive for such low frequencies as the antenna will not pick up that low frequency very well. So not much energy can reach the RFID chip and it should be nearly impossible to damage it that way.
So as far as I can see there can be no issue.