Even card issuer response can vary greatly. Most of the time in the US the issuers will just give you a courtesy adjustment to the account. It requires a material difference ~$5-10 before they'll even think of filing a chargeback. With a DCC markup of 3% minimum, that means you have to get hit with a transaction with DCC over $200+ US before things would probably go to a chargeback.

However, my question is whether or not the card issuer would even let the purchase go to a chargeback? In percysmith's case at Harrods, he charged £50. Let's use the current exchange rate of 630 HKD. Now, for illustrative purposes, let's say the DCC markup was 4% or about 25 HKD (about $3.25 US). He was saying that the issuer may say that the 25 HKD constitute exchange rate fluctuations. It's even more nebulous in his case because his card has a foreign exchange charge, not a foreign transaction fee which is common for US issued cards. So if the FEC is 2%, then it wouldn't be much less than the DCC charge.

If it did go to a chargeback, what bearing would Harrods having provided a refund have on the outcome, especially if you had signed an invalid signature? While Visa/MC do not require a void function, doesn't this open them up to liability in the case that you say, "I did not receive goods/services that I anticipated."?

Wouldn't it be just an authorization instead of a sales, if you do not sign?

I believe it is like what I said in the US. Once we tried to purchase something, and after swiping we saw some errors in the amount, so we didn't sign.

The authorization disappeared days later, and the cashier didn't do anything at that moment...

I suppose the question can be answered by restating the facts from Harrods "the customer was charged, had some problem with the way he was charged and refused to sign/provided crappy signature, so we refunded his money".

Then I have to go find someone to accept the refund was incomplete without being fobbed off by generic statements about exchange rates.

No, they say "amount refunded to customer"

I think with most POS at shops, charges will post unless something is done to stop it (i.e. a void).

With Harrods/GL-type POSes, everything will post. Errors will be handled by way of refund.

I think there might be a difference between US and UK on this one.

In US, the swiping does not generate sales, but authorization (this is based on my personal experience, so it is highly likely to be wrong). In the US, if I don't sign, a transaction cannot be completed, because the final and most important step of signing is not done, which doesn't give cardholder's permission to the transaction.

Likewise, in the UK, I wonder what would happen if someone insert their card, see the amount, but don't input their PIN (obviously they use Chip and PIN). Again, I think the transaction shouldn't be completed, because the cardholder does not provide the permission by not keying the PIN, right?

I don't think Harrods/GL are representative of all of UK/France.

I belive Harrods/GL POSes also seek an authorisation at first also. They just simply don't allow voids so they don't have to perform End Of Day Reconciliation - the register must equal the credit card charges.

Just as a follow-up and as we all suspected, the NTD 5500 rate was honored, and the transaction finally posted to my account at $183.07. The Visa calculator doesn't have TWD as an option to see the exchange rate, but I think Visa used 30.04 TWD = 1 USD for September 15th based on two other transactions that posted today from Watsons (my personal store ;)) and Taiwan HSR.

Had this transaction been hit with DCC the hotel would have made an easy $8.96 off of me at a markup of 4.89% compared to the rate Visa used. :td:

I had an interesting DCC experience at the doctor's office this morning.

They use 农业银行 as their acquirer, and the POS defaults to DCC (of course).

Since I had an hour to kill, I decided to attempt to solve the problem. The first call was to 农行. They explained to the receptionist and I that foreign cards get charged an extra 3.6% because that's a transaction cost. The receptionist blindly took the bait until I showed her this article:

http://flyformiles.flyday.hk/%E7%A2%...on%EF%BC%89-2/

The next call was to the POS machine company, which explained how to reject DCC (similar to other machines). We tried this, and it didn't work... then the POS remembered that 农行 altered the machines that it provides to merchants to conform with its "own standards".

A follow up call to 农行 ensued, which echoed the party line of call #1 (different manager this time).

In the end, I used a Chinese card, but told the office manager there that they'd be wise to fix this since half of their customers are foreigners, and DCC amounts to stealing from them. I doubt they really care though.

Is it 和睦家医院?

So we do have this kind of unbeatable machines, which is like actually really in violation of Visa rules?

No. It's a small chain that only has offices in Shenzhen. I'm not inclined to shame them here yet because they actually seem to be trying to do something about the issue. ABC is giving them a serious run around... including a suggestion to take it up with Visa International; I applaud their tenacity.

I would almost call it a flagrant violation of visa rules; the fact that the guy at the POS company was stumped leads me to think that an opt out actually might not exist at all (or that it's such a tightly kept secret that nobody remotely close to the front lines has a clue about it).

All the methods tried? hitting cancel, looking for a option menu, supervisor password, etc???

Man, it's a tough world out there...

Again, we had the tech support guy from the POS company on the phone for 20 minutes (actually two 10 minute calls). None of his suggested techniques worked.

Did he suggest something that are new to us (other than the cancel button trick) ? I mean, some tricks might be working on other machines~

And did you have the feeling that this tech guy know the DCC stuff?

Apart from "press the cancel button when the DCC screen pops up" (it doesn't!), he gave us 3 different 4-digit codes to enter pre-transaction. I'm not sure this guy knew or cared about DCC, but he certainly knew how to make his company's (unmodified) POS machines churn out RMB receipts.

So what you are saying is that 农行 actually have people modify the POS after they purchase those POS from a vender that already provide DCC-enabled machines?

wow...