Will prices really be different for cash and cards?
I think the question relates to the discussion here: http://clarkhoward.com/liveweb/shownotes/2010/10/05/19449/ It was always the case that merchants could discount purchases made with cash.  What wasn't allowed is allowing the merchant to charge extra for credit card transactions (presumably to cover the fees the merchants pay).  These fees usually carry a flat fee per transaction, plus around 2% of the purchase price.  What also wasn't allowed was them to refuse any credit transactions.  People could charge a pack of gum, even if the fees put that transaction in the red. What's allowed according to this new development is different levels of discounting for different credit cards. Somewhat related to this discussion is another development that happened this summer: merchants now have the ability to refuse credit card transactions of less than $10. Here's my feeling on all of this.  I think we'll see merchants imposing minimum credit transaction amounts before we see them monkeying at the 1-2% level on pricing for different types of credit cards.  My feeling is that they'd be wise not to change anything, even though they can.  Refusing transactions (or charging more for others) is going to come as a unpleasant shock to enough people that they may take their business elsewhere. There are many gas stations where I live that already have different prices if you pay for cash vs. credit.  In addition, some small businesses are doing this as well.  My wife bought a birthday cake from a bakery.  If you paid with cash, you saved 5%. I would say minimal price differences.  Stores will need to remain competative, and the difference (if any) will likely be to cover the cost of the transaction that Visa and other card companies charge them. My guess would be for small merchants there could be a small difference. For large merchants, the cash is also at a cost equivalent to the card fees. Check for my other answer at  How do credit card companies make profit?
The United States Federal Reserve has decided that interest rates should be low. (They think it may help the economy. The details matter little here though.) It will enforce this low rate by buying Treasury bonds at this very low interest rate. (Bonds are future money, so this means they pay a lot of money up front, for very little interest in the future. The Fed will pay more than anyone who offers less money up front, so they can set the price as long as they're willing to buy.) At the end of the day, Treasury bonds pay nearly no interest.   Since there's little money to be made with Treasuries, people who want better-than-zero returns will bid up the current-price of any other bonds or similar loan-like instruments to get what whatever rate of return that they can. There's really no more than one price for money; you can think of the price of those bonds as basically (Treasury rate + some modifier based on the risk) percent.  I realize thinking about bond prices is weird and different than other prices (you're measuring future-money using present-money and it's easy to be confused) and assure you it ultimately makes sense :) Anyway. Your savings account money has to compete with everyone else willing to lend money to banks. Everyone-else lends money for peanuts, so you get peanuts on your savings account too. Your banking is probably worth more to your bank on account of your check-card payment processing fees (collected from the merchant) than from the money they make lending out your savings (notice how many places have promotional rates if you make your direct deposits or use your check card to make a purchase N times a month).  In Europe, it's similar, except you've got a different central bank. If Europe's bank operated radically differently for an extended period of time, you'd expect to see a difference in the exchange rates which would ultimately make the returns from investing in those currencies pretty similar as well. Such a change may show up domestically as inflation in the country with the loose-money policy, and internationally as weakness against other currencies. There's really only one price for money around the entire world. Any difference boils down to a  difference in (perceived) risk. You're right to keep the oldest one.  That's an asset to your credit rating. Since you're already responsible with your credit, a dip in your credit rating doesn't really matter unless you're looking for another loan, like a mortgage. I personally like the cash-back rewards because they're the most flexible, so you have a good thing going with that card. Do those reward cards give you perks on all of your purchases?  If they do, then look carefully to see if you can do noticeably better with another card.  If not, it may not really be worth it. Regarding cancelling one of the cards, I wouldn't, and here's why.  Your cards can get compromised, and sometimes more than one gets compromised at the same time.  I was glad that I had three cards, because two of them got hit the same day.  Hence, having three cards hit on the same day is possible, and you'll be glad that you have the fourth. "You ask about the difference between credit and debit, but that may be because you're missing something important. Regardless of credit/debit, there is value in carrying two different cards associated with two different accounts. The reason is simply that because of loss, fraud, or your own mismanagement, or even the bank's technical error, any card can become unusable for some period of time. Exactly how long depends what happened, but just sending you a new card can easily take more than one business day, which might well be longer than you'd like to go without access to any funds. In that situation you would be glad of a credit card, and you would equally be glad of a second debit card on a separate account. So if your question is ""I have one bank account with one debit card, and the only options I'm willing to contemplate are (a) do nothing or (b) take a credit card as well"", then the answer is yes, take a credit card as well, regardless of the pros or cons of credit vs debit. Even if you only use the credit card in the event that you drop your debit card down a drain. So what you can now consider is the pros and cons of a credit card vs managing an additional bank account -- unless you seriously hate one or more of the cons of credit cards, the credit card is likely to win. My bank has given me a debit card on a cash savings account, which is a little scary, but would cover most emergencies if I didn't have a credit card too. Of course the interest rate is rubbish and I sometimes empty my savings account into a better investment, so I don't use it as backup, but I could. Your final question ""can a merchant know if I give him number of debit or credit card"" is already asked: Can merchants tell the difference between a credit card and embossed debit card? Yes they can, and yes there are a few things you can't (or might prefer not to) do with debit. The same could even be said of Visa vs. Mastercard, leading to the conclusion that if you have a Visa debit you should look for a Mastercard credit. But that seems to be less of an issue as time goes on and almost everywhere in Europe apparently takes both or neither. If you travel a lot outside the EU then you might want to be loaded down with every card under the sun, and three different kinds of cash, but you'd already know that without asking ;-)" Lots of places in the US do it.  Although the way that they usually phrase it is 'prices reflect a x.x% discount for cash' since most of the credit card companies have an agreement that says you cannot charge a surcharge if someone is using a credit card.  So they get around it by giving a discount for cash.   effect is the same, but it skirts the letter of the agreement Please don't waste any more time feeling bad for merchants for the charges they incur. I don't know who supported the lobby for this rule, but issuers no longer can demand that merchants accept all transactions (even the unprofitable ones).  I discussed this at length on my blog. Merchants accept credit cards for one reason, and one reason only: it brings them more business.  More people will buy, and on average they'll buy more.  They used to take the occasional hit for someone buying a pack of gum with a credit card, but they don't have to anymore.  The new law restricts issuers from imposing minimum transactions that are less than $10. I use a rewards card wherever possible.  I get a cheaper price.  In most cases I don't care what the merchant has to pay.  They've already factored it into their prices. But if you are concerned, then as fennec points out in his comment, cash is the way to go. Credit cards also take a cut.  Canada's interac system (use your bank card at the POS to instantly transfer money from your bank to the store) costs merchants 15 cents per transaction.  Visa and Mastercard charge about 3% per transaction.  They justify this by saying that cards encourage people to spend more and stores can make bigger sales.  With cash, I am limited to what's in my pocket, but with visa or interac, if something is just a little more expensive than I'd planned on spending, it's no big deal, I just swipe the card, type my pin and have the product.  If the option is between a sale -x%, or no sale at all, the former beats the latter.  Square is offering a service that is convenient as hell, and they make it very easy to set up and use.  Convenience and ease of use are something that people are willing to pay for. While in the UK and travelling to Europe, I heard of the FairFX euro card from the website Money Supermarket (affiliate link which waives the sign-up fee). The link also includes many other alternative prepaid euro cards which may be better suited for your uses.  The FairFX card is available in both GBP and EUR, and both products come with chip and pin. They also charge relatively little as compared to most bank cards (no currency conversion on use, $2~ withdrawal charges from ATM).  I generally had a good experience with this card, and was able to purchase items both in person as well as online using it. Credits are expensive, so it's a great advantage to pay in cash. Obviously, it's even more an advantage to pay in cash for a house or a car, of course if you can afford it. But, as annoying as it could be, there are some services, where you're out of option to pay in cash, or even to pay by bank transfer. One of the most prominent examples, Google Play (OK, as I've learned, there are prepaid cards. But Groundspeak, for example, has none.). With the further expansion of Internet and E-Economy there will be more cases like that, where paying in cash is no more an option. Booking of hotels or hostels is already mentioned. There are some that provide no other booking option that giving your credit card number. However, even if the do, for example bank transfer of, say, 20% as reservation fee, please note that international money transfer can be very expensive, and credit card is usually given only for security in case you don't come, and if you do come and pay in cash, no money is taken = no expensive fee for international money transfer and/or disadvantaging currency exchange rate.