Differences between EMV chip sizes/number of contacts?

[gibeon]

I just noticed tonight that some cards have a 6-contact (or is it 7?) EMV chip (capital one, NFCU, USAA, Discover...) and some have 21-contact emv chips (Barclays, Wells Fargo, Chase).

I wasn't able to find anything online. But, as there are a lot of credit-card obsessed folks on here, I thought someone might know.

Thanks,

Gib

[alkaline]

Interested in this too. Looking forward to a response.

[nyancat]

You have your contact counts way off, count again there are 6 and 8-contact chips. The 8-contact ones can run a different OS, and cost a little more. No difference to the consumer.

[UncleB]

I had to pull my own cards out and take a look... LOL!

All of my cards (various Capital One, Amex, USAA, Discover cards) all have six contacts.  Even my Synchrony/Sam's Club Mastercard, which appears to have eight contacts, upon a closer look only has six.

I will note, though, that the pictures of Amex 'dual interface/chip + contactless' cards I've seen do have a contact pad that looks different, specifically it's larger.  I don't have one myself, though.

[nyancat]

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@UncleB wrote:

I had to pull my own cards out and take a look... LOL!

All of my cards (various Capital One, Amex, USAA, Discover cards) all have six contacts.  Even my Synchrony/Sam's Club Mastercard, which appears to have eight contacts, upon a closer look only has six.

I will note, though, that the pictures of Amex 'dual interface/chip + contactless' cards I've seen do have a contact pad that looks different, specifically it's larger.  I don't have one myself, though.

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In the US, Barclay's and Chase use 8-contact chips. Almost everyone else is using 6-contact chips. Again, the only difference is the OS they can run, which doesn't matter to us as customers.

6-contact dual-interface chips are physically almost as large as 8-contact chips to allow for the radio, as you've noticed.