Why do credit cards have minimum limits?
I believe it's just to limit the less well-off from acquiring one. If your credit history and income do not support a $15,000 credit limit, then don't even think about applying for an Altitude Black card. If they do, then don't bother with a student card. It's primarily about market segmentation by wealth or income. They have a minimum to discourage applications for that particular card. Every application costs them money because they have to pay the credit agencies to pull the applicant's credit history. So one way they save money and reduce their cost of business is to discourage people from applying if they're not creditworthy enough for that product. Credit card companies tailor their products into different income/credit brackets. Those who have less creditworthiness would be better suited for a different product than what you're referring, similar to those with greater creditworthiness. It discourages people from obtaining a high-limit card simply to show off, because the bank's forcing them to use it or lose it.
At least in the US, many credit card companies offer statements that categorize your spending on that card and break it down by different categories depending on the merchant category code.   Having different cards for each budget category can be a good idea if different cards have different rewards bonuses depending on categories: e.g. this card gives a high percentage back at gas stations, that one at grocery stores, another at restaurants, etc. 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. "@Joe's original answer and the  example with proportionate application of the payment to the two balances is not quite what will happen with US credit cards. By US law (CARD Act of 2009), if you make only the minimum  required payment (or less), the credit-card company can choose which part of the balance that sum is applied to. I am not aware of any company that chooses to apply such payments to anything other than that part of the balance which carries the least interest rate  (including the 0% rate that ""results"" from acceptance of balance transfer  offers). If you make more than the minimum required payment, then the excess must, by law, be applied to paying off the highest rate balance. If the highest rate balance gets paid off completely, any remaining amount must be applied to second-highest rate balance, and so on.  Thus, it is not the case that that $600 payment (in Joe's example) is applied proportionately to the $5000 and $1000 balances owed. It depends on what the required minimum payment is. So, what would be the minimum required payment? The minimum payment is the total of (i) all finance charges incurred during that month, (ii) all service fees and penalties (e.g. fee for exceeding credit limit, fee for taking a cash advance, late payment penalty) and other charges (e.g. annual card fee) and (iii) a fraction of the outstanding balance that (by law) must be large enough to allow the customer to pay off the entire balance in a reasonable length of time. The law is silent on what is reasonable, but most companies use 1% (which would pay off the balance over 8.33 years).  Consider the numbers in Joe's example together with the following assumptions: $5000 and $1000 are the balances owed at the beginning of the month, no new charges or service fees during that month, and the previous month's minimum monthly payment was made on the day that the statement paid so that the finance charge for the current month is on the balances stated). The finance charge on the $5000 balance is $56.25, while the finance charge on the $1000 balance is $18.33, giving a minimum required payment of $56.25+18.33+60 = $134.58. Of the $600 payment, $134.58 would be applied to the lower-rate balance ($5000 + $56.25 = $5056.25) and reduce it to $4921.67. The excess $465.42 would be applied to the high-rate balance of $1000+18.33 = $1018.33 and reduce it to $552.91. In general, it is a bad idea to take a cash advance from a credit card. Don't do it unless you absolutely must have cash then and there to buy something from a merchant who does not accept credit cards, only cash, and don't be tempted to use the ""convenience checks"" that credit-card companies send you from time to time. All such cash advances not only carry larger rates of interest (there may also be upfront fees for taking an advance) but any purchases made during the rest of the month also become subject to finance charge. In other words, there is no ""grace period"" for new charges, and this state of affairs will last for one month beyond the first credit-card statement whose statement is paid off in full in timely fashion. Finally, turning to the question asked, viz. "" I am trying to determine how much I need to pay monthly to zero the balance, ...."", as per the above calculations, if the OP makes the minimum required payment of $134.58 plus $1018.33, that $134.58 will be applied to the low-rate balance and the rest $1018.33 will pay off the high-rate balance in full if the payment is made on the day the statement is issued. If payment is made later, but before the due date, that $1018.33 will be accruing finance charges until the date the payment is made, and these will appear as 22% rate balance on next month's statement. Similarly for the low-rate balance. What if several monthly payments will be required? The best calculator known to me is at https://powerpay.org (free but it is necessary to set up a username and password).  Enter in all the credit card balances and the different interest rates, and the total amount of  money that can be used to pay off the balances, and the site will lay out a payment plan.  (Basically, pay off the highest-interest rate balance as much as possible while making minimum required payments on the rest). Most people are surprised at how much can be saved (and how much shorter the time to be debt-free is) if one is willing to pay just a little bit more each month." Given that the laws on consumer liability for unauthorized transactions mean no cost in most cases, the CVV is there to protect the merchant.  Typically a merchant will receive a lower cost from their bank to process the transaction with the CVV code versus without. As far as the Netflix case goes, (or any other recurring billing for that matter) they wouldn't care as much about it because Visa/MC/Amex regulations prohibit storage of the CVV.  So if they collect it then it's only used for the first transaction and renewals just use the rest of the card info (name, expiration date, address). Does the presence of CVV indicate the merchant has better security?  Maybe, maybe not.  It probably means they care about their costs and want to pay the bank as little as possible to process the transaction. Because your friend isn't going to like the ~2% charge they have to pay to the credit card company on the $10,000 purchase. Credit card companies make money off of transactions. The cardholder normally doesn't pay any transaction fees (and in fact can make a profit via rewards), but the merchant has to pay a certain amount of money to the credit card company for the transaction. In this case, the apartment owners ate the charge, likely because it was easier for them to send a check than to refund the cost of the fee through the credit card company. If you started doing this a lot to take advantage of this, I would imagine they would get smart and refuse your business (it'll be pretty obvious what you're doing if you're not signing any leases). Many people, especially with lower income/skill/education, have poor money management skills to the point where they will not be able to ration their money for a full month. If the payment schedule is reduced to weekly or bi-weekly it becomes easier for such people to make non-discretionary payments. I don't think there's any law against having lots of bank accounts. But what are you really gaining? Every new account is a paperwork hassle. Every new account is another target for con men who might steal your information and write bad checks or make phony credit card purchases in your name. Yes, it's not unreasonable to have a credit card or two that you keep for emergencies. I'd advise anyone with running up debts while having no idea how you will pay them off. But to say that you might keep some credit available so that if you have a legitimate emergency -- like, say, your car breaks down and you don't have the cash to fix it and you can't get to work without it -- you have some a fallback. But do you really need ten credit cards for that sort of thing? And how much credit are they giving you on each card? I don't know how the banks work this, but I'd think if they're rational, they'd consider your total credit before giving you more.  I have three credit cards that I use regularly -- two personal and one business. And I find that a real pain to keep track of, to make sure that I keep each one paid by the due date and to keep a handle on how much I owe and so forth. I can't imagine trying to deal with ten. I suppose you could just stuff all these cards in a drawer and only use them in case of emergency. Even if you can get a credit card with a $0 limit, that doesn't necessarily mean that the charges won't succeed. Some of my credit cards have gone over limit by a significant amount (e.g. 140% of limit) without any transactions being declined. The limit just means that the bank is allowed to decline the transaction, but they are also allowed to approve it anyway. So basically what you would have is a credit card where any transaction can always be declined or approved. "There is also the very simple fact that cash is a *significantly* self-limiting thing: you are limited in amount you can spend on any give day to the cash you have on hand -- this along makes you either reticent to spend it, forces you to spread your purchases (or forgo one in order to enable another), and/or requires additional planning to spend larger amounts.  Conversely, most debit &amp; credit cards while they also have some limits on them, enable far more free spending.  So whether the spending of cash is a negative ""painful"" reaction, or really just an awareness that their available resource is being reduced, would be a better question.  After all, similar things are seen in other things that have short-term physical limits: smokers tend to smoke cigarettes more quickly at the beginning of a new pack, and tend to space out the intervals between them as the pack empties; likewise with other resources (food, beer, soda) within a home -- if/when the supply is abundant, we tend to gorge &amp; snack, as the available supply decreases, we cut back." some of that article is misleading, some of it is just plain wrong. Very wrong... like you end up drawing an incorrect conclusion type wrong.  Corporate transaction accounts, whose balances are up recently due to TAG (expires 12/31), are subject to reserve requirements.  When you purchase something with a credit card, the bank's asset of your credit increases and the bank's asset of cash decreases (it goes wherever you purchased).  There is no change to your deposit account and no change to reserves.  The incoming bank's cash account and liability account associated with that business transaction account increase, and it is trivial to transfer the % of cash necessary to reach minimum reserve requirements to the Fed.  Secondly, anyone with a smidgen of accounting can tell that his balance sheet won't balance. I'm not sure if you are including the use of credit cards in the intent of your quesiton.  However, I will give you some good reasons I use them even when I can pay cash: 1) I get an interest free loan for almost 30 days as long as I don't carry balances. 2) I get a statement detailing where I am spending my money that is helpful for budgeting. I'd never keep track to this level of detail if I were using cash. 3) Many cards offer reward programs that can be used for cash back. 4) It helps maintain my credit rating for those times I NEED to buy something and pay it off over time (car, house, etc.) 5) Not so much an issue for me personally, but for people that live paycheck to paycheck, it might help to time your cash outflows to match up with your inflows. For a business, I think it is mostly a cash flow issue. That is, in a lot of B2B type businesses customers can pay very slowly (managing their own cash flows). So your revenue can sometimes lag quite a bit behind the expenses that were associated with them (e.g payroll). A business line of credit can smooth out the cash flow, especially for companies that don't have a lot of cash reserves. A lot of stores, especially smaller ones, won't accept card payments under $10.00. They pay a fee for taking cards and for small transactions it is not worth it. a typical debit card is subject to several limits: I have a Citi card that gives me checks all of the time.  Most of the time it requires the 3%/minimum $10 or whatever, but occasionally when they're trying to sucker you into borrowing money from them they will let you take $1,500 w/ no fee for 6 months.  Outside of that I've never seen it exist in modern credit cards. "I'd like to modify the ""loss"" idea that's been mentioned in the other two answers.  I don't think a retail location needs to be losing money to be a candidate for sale.  Even if a retail location is not operating at a loss, there may be incentive to sell it off to free up cash for a better-performing line of business. Many large companies have multiple lines of business.  I imagine Sunoco makes money a few ways including: refining the gas and other petroleum products, selling those petroleum products, selling gas wholesale to franchised outlets or other large buyers, licensing their brand to franchised outlets, selling gas and convenience items direct to consumers through its own corporate-owned retail outlets, etc. If a company with multiple lines of business sees a better return on investment in certain businesses, it may make sense to sell off assets in an under-performing business in order to free up the capital tied up by that business, and invest the freed-up capital in another business likely to perform better. So, even ""money making"" assets are sometimes undesirable relative to other, better performing assets. Another case in which it makes sense to sell an asset that is profitable is when the market is over-valuing it.  Sell it dear, and buy it back cheap later."