Why do credit card transactions take up to 3 days to appear, yet debit transactions are instant?
When you swipe your credit card, the terminal at the store makes a request of your bank, and your bank has only a few seconds to accept or reject the transaction. Once the transaction is accepted by your bank, it appears in the Pending transactions. At the end of the business day, the store submits all of the final transactions for the day to their bank in a batch, and the banks all trade transactions in a batch, and money is sent between banks. This is the process that takes a couple of days, and after this happens, you see the transaction move from your Pending transactions into the regular transactions area.  Most of the time, the pending transaction and the final transaction are the same. However, there are cases where it is different. A couple of examples: With a credit account, the fact that the final amount is not known for a few days is no big deal: after all, you don't have any money in the account, and if you end up spending more than you have, the bank will happily let you take your time coming up with the money (at a steep cost, of course). With a debit card tied to your checking account, the transaction is handled the same way, as far is the store is concerned. However, your bank is not going to run the risk of you overdrawing your checking account. They also are not going to run the risk of you withdrawing money from your account that is needed to cover pending transactions. So they usually treat these pending transactions as final transactions, deducting the pending transaction from your account balance immediately. When the final transaction comes through, they adjust the transaction, and your balance goes up or down accordingly. This is one of the big drawbacks to using a debit card, in my opinion. If a bad pending transaction comes through, you are out this money until it gets straightened out. Take a look at http://en.wikipedia.org/wiki/Payment_gateway There is essentially a lead time between when the transaction is made and when it is settled, 2-3 business days is the lead time for settlement. The link explains the process step-by-step
"As stated in the other answer, debit card payments even contactless ones, do not debit instantly or anywhere near instantly. They can take several days or even longer. However, the fact that the payment was approved would indicate that the contactless device used by the retailer managed to connect to your bank account and could see there were sufficient funds.  At this time the payment should also have ""reserved"" the funds so it will be ""pending"" as such.  Your online banking may not show all types of pending transactions, it may only show Direct Debits for example, if you ring the bank I expect they will be able to see this payment and advise accordingly, out of interest who do you bank with? If you can see your ""available"" funds you should find that includes this payment having been ""reserved"" ie you can't use that money, but if it's a small amount you may struggle to spot it.  Again, this will vary by bank and how their internet banking system has been implemented. I would expect this payment to debit your account the working day after you made it, or at worst the day after that.  In theory with ""faster payment"" technology it could happened within 2 hours but not all banks implemented that system in the same way so delays can and do occur.  If the retailer/merchant banks with the same bank you do, in theory the transaction could be instantaneous, again depending on the bank. Short answer short, the transaction is fine, it won't be void, you just need to wait, probably a day or two. This link has more info, especially useful if you bank with NatWest (as I say the technology is likely to vary by bank to some extent).  Your own bank should have their own version of this. http://personal.natwest.com/personal/current-accounts/your-visa-debit-card/contactless.html" Is there not some central service that tracks current currency rates that banks can use to get currency data? Sure.  But this doesn't matter.  All the central service can tell you is how much the rate was historically.  But the banks/PayPal don't care about the historical value.  They want to know the price that they'll pay when they get around to switching, not the last price before the switch.  Beyond that, there is a transaction cost to switching.  They have to pay the clearinghouse for managing the transaction.   The banks can choose to act as a clearinghouse, but that increases their risk.  If the bank has a large balance of US dollars but dollars are falling, then they end up eating that cost.  They'll only take that risk if they think that they'll make more money that way.  And in the end, they may have to go on the currency market anyway.  If a European bank runs out of US dollars, they have to buy them on the open market.  Or a US bank might run out of Euros.  Or Yen.  Etc.   Another problem is that many of the currency transactions are small, but the overhead is fixed.  If the bank has to pay $5 for every currency transaction, they won't even break even charging 3% on a $100 transaction.  So they delay the actual transaction so that they can make more than one at a time.  But then they have the risk that the currency value might change in the meantime.  If they credit you with $97 in your account ($100 minus the 3% fee) but the price actually drops from $100 to $99, they're out the $1.   They could do it the other way as well.  You ask for a $100 transaction.  They perform a $1000 transaction, of which they give you $97.  Now they have $898 ($1000 minus the $5 they paid for the transaction plus the $3 they charged you for the transaction).  If there's a 1% drop, they're out $10.98 ($8.98 in currency loss plus a net $2 in fees).   This is why banks have money market accounts.  So they have someone to manage these problems working twenty-four hours a day.  But then they have to pay interest on those accounts, further eating into their profits.  Along with paying a staff to monitor the currency markets and things that may affect them. It is absolutely worth it.  My wife and I have two of these accounts (different banks).  We are required to use our cards 20 times for one bank, and 15 for the other.  We have yet to miss the required transactions in a month (over 15 months of use now), and are actually considering getting a third account.  Between the two of us, we simply have to use our card on average once a day. Getting gas? Use your debit card. Getting stamps? Use your debit card? Self checkout? Use your debit card twice. Eating out? Use your debit card. If married, split the bill. As soon as we reach the minimum, we stop using the debit cards and switch to credit cards to further boost the rewards.  Maybe it's easier for us since we don't have kids and are out a lot, but 12 transactions is really simple to obtain.  We receive ~$100 a month from our two accounts, all for doing something we already do. I am using my debit card regularly: in ATM's with a pin, in stores with my signature, and online. But later you say  But from what I recall from starting my own business (a LONG time ago), for debit cards there's only a per-transaction fee of like $0.25, not a percentage cut. Only pin transactions have just a per-transaction fee paid by you to the merchant (and you are reimbursed by Schwab).  If you use your card with just a signature or online without a pin, then it is a credit transaction from the merchant's perspective.  The merchant pays a fee and Schwab gets its cut of that.  So for two of the transaction types that you describe, the merchant pays Schwab (indirectly) out of your payment.  Only when you enter your pin does it process as a debit transaction where Schwab pays the merchant.   Because check cards withdraw the money from your account immediately, you don't even get the twenty to fifty day grace period.  So those merchant fees are pure profit for Schwab, offsetting the loss from the ATM fees.   You claim $4-5k in fees at $.25 each.  That's sixteen to twenty thousand transactions.  Assuming that several is four to five years, that's more than ten transactions a day.  That seems like a lot.  I can see three for meals, one for miscellaneous, and maybe some shopping.  But if I go shopping one day, I don't normally go again for a while.  I have trouble seeing a consistent average of five or more transactions a day.   Even if we use just the higher ATM fees (e.g. $2), that's still more than a transaction a day.  That's an extreme level of usage, particularly for someone who also makes frequent purchases via card.   I haven't done any other business with them. I find this confusing.  How does money get into your account?  At some point, you must have deposited money into the account.  You can't debit from an account without a positive balance.  So you must have done or be doing some kind of business with them.  If nothing else, they can invest the balance that you deposit.  Note that they make a profit off such investments.  They share some of that profit with you in the form of interest, but not that much really.   Of course, Schwab may still be losing money on your transactions.  We can't really tell without more information on how much of each transaction type you do and how much of a balance you maintain.  Perhaps they are hoping that you will do other, more profitable, activities in the future.   I doubt there are that many Schwab customers like you describe yourself.  As best I've been able to see, they advertise their banking services just to investment customers.  So it's unlikely that many customers who don't use their investment services use their banking services just for ATM reimbursements. It comes down to liability - if a fraudulent transaction takes place with a debit card, you are out $$ until it is resolved - while as with a credit card, the credit lender is out $$ - the credit lender does not like losing $$, and therefore would like to be paid extra $$ for assuming this risk, and they found the merchant as the one most willing to pay. Sometimes the merchant will pass on this cost to the consumer, but often times the credit card company has a contract with the merchant preventing such a fee, because then they would be at a price disadvantage when compared to debit. In the US, paper checks are still the rule, and there is a large amount of the population that does not care to use online banking. As a result, those people need to go to the bank once a week or more often, to deposit checks they get from anywhere, to get cash, etc.; so all those little banks have traffic. This is slowly changing, and banks start to automatic the processes even in the brick-and-mortar location, but for now, they are around. Some companies have banks and brokerages that are completely separate systems. So you could be actually running ACH transactions between two different banking entities. Bank of America used to have significant latency between BoA accounts, because they ran into delays integrating Fleet, BankSouth and BoA systems. Generally, unless you're doing a wire transfer, bank transactions are processed in batches overnight. So the credit card company won't be able to confirm your transfer until the next business day (it may take even longer for them to actually receive the money).