Why do banks insist on allowing transactions without sufficient funds?
The reason they want the transaction to go through is because they make money that way. Remember the overdraft protection might incur a fee. If it does their experience may show them that the fee is a greater source of profit when balanced against the losses incurred because of insufficient funds. Even free overdraft transactions are limited. If they didn't want to make money they would have a way to make sure that multiple overdrafts in a short time window wouldn't require multiple protection events. Remember each time they transfer funds they only bring you to zero. As it is now the coffee you buy after putting money on your subway fare card might also trigger an overdraft transfer. Believe it or not, this is done as a service to you. The reason for this has to do with a fundamental difference between a credit card account and a checking account.  With a credit card account, there is no money in the account; every charge is borrowed money. When you get to your credit limit, your credit transactions will start getting declined, but if the bank does for some reason let one get approved, it's not a big deal for anyone; it just means that you owe a little more than your credit limit. Note that (almost) every credit card transaction today is an electronic transaction.  A checking account, however, has real money in it. When it is gone, it is gone. When a balance inquiry is done, the bank has no way of knowing how many checks you've written that have not been cashed yet. It is a customer's responsibility to know exactly how much money is available to spend.  If you write more checks than you have money for in your account, technically you have committed a crime. Unfortunately, there are too many people now that are not taking the responsibility of calculating their own checking account balance seriously, and bad checks are written all the time. When a bank allows these transactions to be paid even though you don't have enough money in your account, they are preventing a crime from being committed by you. The fee is a finance charge for loaning you the money, but it is also there to encourage you not to spend more than you have.  Even if you use a debit card, it is still tied to a checking account, and the bank doesn't know if you have written enough checks to overdraw your account or not. It is still your responsibility to keep track of your own available balance.  Every time this happens to you, thank the bank as you pay this fee, and then commit to keeping your own running balance and always knowing how much you have left in your account. The laws about this changed in 2010 with the new Overdraft Protection Law HR 1261.  § 140B. (c) Consumer consent opt-In.—A depository institution may   charge overdraft coverage fees with respect to the use of an automatic   teller machine or point of sale transaction only if the consumer has   consented in writing, in electronic form, or in such other form as is   permitted under regulations of the Bureau. Now when you sign up for a bank account you have to opt in to overdraft coverage (the bank transfers funds from other accounts to cover overdrafts), or overdraft protection (the bank simply bounces NSF checks).  I'm pretty sure you could always set this option on your account, but banks were defaulting everyone's account that didn't think to ask such that overdrafts got paid and incurred fees. The law now prohibits them from using that as the default option. This really should be a comment, but I can't yet. The question desperately needs a location tag. In at least some countries(New Zealand), the default action on all insufficient funds transactions is to refuse the transaction. Credit cards are the only common exception. Every bank operating in NZ that I know of acts this way. Sometimes there is a fee for bouncing a transaction, sometimes not, that depends on the bank. Any other option must be explicitly arranged in writing with the bank. Personally, coming from a country where declining transactions is the default, I'd be shocked and angry to be stuck with an automatic transfer from another account. Angry enough to change banks if they won't immediately cease and desist.
Banks are not your friends, they are not performing services for you because they like you. They are a business, and they make money by borrowing money from you at low interest and loaning it out at higher interest. They are trying to persuade you to deposit more money (however briefly) in their bank so they can loan out more money. They are probably also counting on the fact that most folks won't go to the trouble of setting up accounts at multiple banks with the interlocking automatic transfers, in order to meet the required deposit threshold. That lets them save on the interest payments to consumers that are individually tiny, but significant in the aggregate. "Let's divide all bank accounts into savings and checking. The main difference is that checking is easy to get money from; savings is hard to get money from. Because of this, the federal Reserve requires that banks keep more money on hand to cover transactions in checking accounts. Here is a related question from a banking customer regarding a recent notice on their bank statement: Deposit Reclassification. It seems that the bank was moving the customer's money between hidden sub accounts to make it look like the checking account was really a savings account and thus ""reduce the amount of funds we are required to keep on deposit at the Federal Reserve Bank."" If they didn't have to transfer the money many times the bank could keep less cash on hand. But once they did 5 hidden transactions the rest of the money in the hidden savings account would be moved by the bank. The 6 transaction limit is done to not allow you to treat savings like checking. Here is a relevant quote from the Federal Reserve Savings Deposits  Savings deposits generally have no specified maturity   period. They may be interest-bearing, with interest computed or paid   daily, weekly, quarterly, or on any other basis. The two most   significant features of savings deposits are the ‘‘reservation of   right’’ requirement and the restrictions on the number of   ‘‘convenient’’ transfers or withdrawals that may be made per month (or   per statement cycle of at least four weeks) from the account. In order   to classify an account as a ‘‘savings deposit,’’ the institution must   in its account agreement with the customer reserve the right at any   time to require seven days’ advance written notice of an intended   withdrawal. In practice, this right is never exercised, but the   institution must nevertheless reserve that right in the account   agreement. In addition, for an account to be classified as a ‘‘savings   deposit,’’ the depositor may make no more than six ‘‘convenient’’   transfers or withdrawals per month from the account. ‘‘Convenient’’   transfers and withdrawals, for purposes of this limit, include   preauthorized, automatic transfers (including but not limited to   transfers from the savings deposit for overdraft protection or for   direct bill payments) and transfers and withdrawals initiated by   telephone, facsimile, or computer, and transfers made by check, debit    card, or other similar order made by the depositor and payable to   third parties. Other, less-convenient types of transfers, such as   withdrawals or transfers made in person at the bank, by mail, or by   using an ATM, do not count toward the six-per-month limit and do not   affect the account’s status as a savings account. Also, a withdrawal   request initiated by telephone does not count toward the transfer   limit when the withdrawal is disbursed via check mailed to the   depositor.  Examiners should be particularly wary of a bank’s practices   for handling telephone transfers. As noted, an unlimited number of   telephone-initiated withdrawals are allowed so long as a check for   the withdrawn funds is mailed to the depositor. Otherwise, the limit   is six telephone transfers per month. The limit applies to telephonic   transfers to move savings deposit funds to another type of deposit   account and to make payments to third parties." Transaction fees are part of the income for banks, and as we know they are profit making corporations just like any other Company. The differene is that instead of buying and packing and Selling groceries, they buy and package and sell Money. Within the rules and the market they will try to maximize their profit, exactly like Apple or GM or Walmart and so on. Sweden and Holland are part of the European union and the leaders of the union has defined (by law) that certain types of transactions should be done without fees. In order to transfer Money from your Swedish account to the Dutch account you do what is called a SEPA transaction, which should be done in one day without cost to you as a customer. Reference: https://en.wikipedia.org/wiki/Single_Euro_Payments_Area Gunnar Limited transactions: what's to stop a firm from having thousands of bank accounts to avoid the limit. This of course is costly.   Tax on transactions: some trades are worth $00.001 and some are $190,000. They shouldn't be taxed the same.   Both increase costs of capital and literally everyone in America pays for it. Investment is more expensive. And our beautiful liquid market is no longer as efficient and can no longer responds as quickly to market forces. Investors now go to other foreign markets that don't limit or charge for transactions. Both plans will cost the economy billions of dollars and for what? So some computers don't trade almost instantaneously? Exactly why is that a problem other than class warfare? A lot of the risks that people have about flash crashes have been mitigated with better algorithms and rules. The Bank Secrecy Act of 1970 requires that banks assist the U.S. Gov't in identifying and preventing money laundering. This means they're required to keep records of cash transactions of Negotiable Instruments, and report any such transactions with a daily aggregate limit of a value greater than (or equal to?) $10,000. Because of this, the business which is issuing the money order is also required to record this transaction to report it to the bank, who then holds the records in case FinCEN wants to review the transactions. EDITED: Added clarification on the $10,000 rule "Banks are in it to make money. But they're expected to provide a social good which powers our economy: secure money storage (bank accounts) and cashless transactions (credit/debit cards).  And the government does not subsidize this.  In fact, banks are being squeezed. Prudent customers dislike paying the proper cost of their account's maintenance (say, a $50/year fee for a credit card, or $9/month for a checking account) - they want it free.  Meanwhile government is pretty aggressive about preventing ""fine print"" trickery that would let them recover costs other ways.  However there isn't much sympathy for consumers who make trivial mistakes - whether they be technical (overdraft, late fee) or money-management mistakes (like doing balance transfers or getting fooled by promotional interest rates).  So that's where banks are able to make their money: when people are imprudent.  The upshot is that it's hard for a bank to make money on a prudent careful customer; those end up getting ""subsidized"" by the less-careful customers who pay fees and buy high-margin products like balance transfers.  And this has created a perverse incentive: banks make more money when they actively encourage customers to be imprudent.  Here, the 0% interest is to make you cocky about running up a balance, or doing balance transfers at a barely-mentioned fee of 3-5%. They know most Americans don't have $500 in the bank and you won't be able to promptly pay it off right before the 0% rate ends.  (or you'll forget).  And this works - that's why they do it.   By law, you already get 0% interest on purchases when you pay the card in full every month.  So if that's your goal, you already have it.  In theory, the banks collect about 1.5% from every transaction you do, and certainly in your mind's eye, you'd think that would be enough to get by without charging interest.  That doesn't work, though.  The problem is, such a no-interest card would attract people who carry large balances.  That would have two negative impacts: First the bank would have to spend money reborrowing, and second, the bank would have huge exposure to credit card defaults.   The thing to remember is the banks are not nice guys and are not here to serve  you.  They're here to use you to make money, and they're not beneath encouraging you to do things that are actually bad for you. Caveat Emptor." "This will happen automatically when you open an interest-bearing account with a bank.   You didn't think that banks just kept all that cash in a vault somewhere, did you?  That's not the way modern banking works.   Today (and for a long, long time) banks will keep only a small fraction of their deposits on hand (called the ""reserve"") to fund daily withdrawals and other operations.  The rest they routinely lend out to other customers, which is how they pay for their operations (someone has to pay all those tellers, branch managers, loan officers) and pay interest on your deposits, as well as a profit for their owners (it's not a charity service).  The fees charged for loan origination, as well as the difference between the loan interest rate and the deposit rate, make up the profit.   Banks rarely hold their own loans.  Instead, they will sell the loans in portfolios to investors, sometimes retaining servicing rights (they continue to collect the payments and pass them on) and sometimes not (the payments are now due to someone else).  This allows them to make more loans.   Banks may sometimes not have enough capital on hand.  In this case, they can make inter-bank loans to meet their short-term needs.  In some cases, they'll take those loans from a government central bank.  In the US, this is ""The Fed"", or the Federal Reserve Bank.   In the US, back around the late 1920's, and again in the 1980's some banks experienced a ""run"", or a situation where people lost confidence in the bank and wanted to withdraw their money.  This caused the bank to have insufficient funds to support the withdrawals, so not everyone got their money.  People panicked, and others wanted to take their money out, which caused the situation to snowball.  This is how many banks failed.  (In the '80s, it was savings-and-loans that failed - still a kind of ""bank"".)  Today, we have the FDIC (Federal Deposit Insurance Corporation) to protect depositors.  In the crashes in the early 2000's, many banks closed up one night and opened the next in a conservatorship, and then were literally doing business as a new bank without depositors (necessarily) even knowing.  This protected the consumers.  The bank (as a company) and its owners were not protected." Once, back when I had a bank account, I tried to pay a large emergency dental bill with my debit card. It rejected it as it turned out the bill was less than a dollar over what I had in the account. I thought there was enough money so I tried again, 3 times. They charged me an overdraft for each attempt even though the debit never went through. This was without overdraft protection, as overdraft protection would have allowed the debit and charged me one overdraft. I don't know the details but federal regulations have changed how they do this.  To me overdraft protection rejects any debit that attempts to overdraft my account and doesn't charge me with an overdraft that didn't actually occur as a result of the charge being rejected, but that's not how it works. It isn't that the companies force traders, it is more the other way around. Traders wouldn't trade without margin. The main reason is liquidity and taking advantage of minor changes in the forex quotes. It goes down to pips and traders make profit(loss) on movement of pips maybe by 1 or 2 and in some cases in 1/1000 or less of a pip. So you need to put in a large amount to make a profit when the quotes move up or down. Supposedly if they have put in all the amount upfront, their trading options are limited. And the liquidity in the market goes out of the window. The banks and traders cannot make a profit with the limited amount of money available at their disposal. So what they would do is borrow from somebody else, so why not the broker itself in this case maybe the forex company, and execute the trades. So it helps everybody. Forex companies make their profit from the fees, more the trades done, more the fees and hence more profit. Traders get to put their fingers in many pies and so their chances of making profits increases. So everybody is happy. "They don't actually need to. They accept deposits for historical reasons and because they make money doing so, but there's nothing key to their business that requires them to do so. Here's a decent summary, but I'll explain in great detail below. By making loans, banks create money. This is what we mean when we say the monetary supply is endogenous. (At least if you believe Sir Mervyn King, who used to run England's central bank...) The only real checks on this are regulatory--capitalization requirements and reserve requirements, which impose a sort of tax on a bank's circulating loans. I'll get into that later. Let's start with Why should you believe that story--that loans create deposits? It seems like a bizarre assertion. But it actually matches how banks behave in practice. If you go borrow money from a bank, the loan officer will do many things. She'll want to look at your credit history. She'll want to look at your income and assets. She'll want to look at what kind of collateral or guarantees you're providing that the loan will be repaid. What she will not do is call down to the vaults and make sure that there's enough bills stacked up for them to lend out. Loans are judged based on a profitability function determined by the interest rate and the loan risk. If those add up to ""profitable"", the bank makes the loan. So the limiting factor on the loans a bank makes are the available creditworthy borrowers--not the bank's stock of cash. Further, the story makes sense because loans are how banks make money. If a bank that was short of money suddenly stopped making loans, it'd be screwed: no new loans = no way to make money to pay back depositors and also keep the lights on = no more bank. And the story is believable because of the way banks make so little effort to solicit commercial deposit business. Oh sure, they used to give you a free toaster if you opened an account; but now it's really quite challenging to find a no-fee checking account that doesn't impose a super-high deposit limit. And the interest paid on savings deposits is asymptotically approaching zero. If banks actually needed your deposits, they'd be making a lot more of effort to get them. I mean, they won't turn up their noses; your deposited allowance is a couple basis points cheaper to the bank than borrowing from the Fed; but banks seem to value small-potatoes depositors more as a source of fees and sales opportunities for services and consumer credit than as a source of cash. (It's a bit different if you get north of seven figures, but smaller depositors aren't really worth the hassle just for their cash.) This is where someone will mention the regulatory requirements of fractional reserve banking: banks are obliged by regulators to keep enough cash on hand to pay out a certain percentage of deposits. Note nothing about loans was said in that statement: this requirement does not serve as a check on the bank making bad loans, because the bank is ultimately liable to all its depositors for the full value of their deposits; it's more making sure they have enough liquidity to prevent bank runs, the self-fulfilling prophecy in which an undercapitalized bank could be forced into bankruptcy. As you noted in your question, banks can always borrow from the Fed at the Fed Discount Rate (or from other banks at the interbank overnight rate, which is a little lower) to meet this requirement. They do have to pledge collateral, but loans themselves are collateral, so this doesn't present much of a problem. In terms of paying off depositors if the bank should collapse (and minimizing the amount of FDIC insurance payout from the government), it's really capital requirements that are actually important. I.E. the bank has to have investors who don't have a right to be paid back and whose investment is on the hook if the bank goes belly-up. But that's just a safeguard for the depositors; it doesn't really have anything to do with loans other than that bad loans are the main reason a bank might go under. Banks, like any other private business, have assets (things of value) and liabilities (obligations to other people). But banking assets and liabilities are counterintuitive. The bank's assets are loans, because they are theoretically recoverable (the principal) and also generate a revenue stream (the interest payments). The money the bank holds in deposits is actually a liability, because it has to pay that money out to depositors on demand, and the deposited money will never (by itself) bring the bank any revenue at all. In fact, it's a drain, because the bank needs to pay interest to its depositors. (Well, they used to anyway.) So what happens when a bank makes a loan? From a balance sheet perspective, strangely enough, the answer is nothing at all. If I grant you a loan, the minute we shake hands and you sign the paperwork, a teller types on a keyboard and money appears in your account. Your account with my bank. My bank has simultaneously created an asset (the loan you now have to repay me) and an equal-sized liability (the funds I loaned you, which are now deposited in your account). I'll make money on the deal, because the interest you owe me is a much higher rate than the interest I pay on your deposits, or the rate I'd have to pay if I need to borrow cash to cover your withdrawal. (I might just have the cash on hand anyway from interest and origination fees and whatnot from previous loans.) From an accounting perspective, nothing has happened to my balance sheet, but suddenly you owe me closing costs and a stream of extraneous interest payments. (Nice work if you can get it...) Okay, so I've exhaustively demonstrated that I don't need to take deposits to make loans. But we live in a world where banks do! Here's a few reasons: You can probably think of more, but at the end of the day, a bank should be designed so that if every single (non-borrowing) depositor withdrew their deposits, the bank wouldn't collapse or cease to exist." "Why would a bank buy government bonds? Why couldn't they just deposit their money in another bank instead?  Generally, banks are limited by laws and regulations about how much they must set aside as reserves. Of the money they receive as deposits, they may loan a certain amount, but must keep some as a reserve (this is called ""fractional reserve banking""). Different countries have a different amount that they must set aside in reserves.  In countries where bank deposits are guaranteed, there is almost always some upper limit to how much is guaranteed. The amount of money that a bank would deposit in another bank would be far greater than the guarantee." Commercial banks are not allowed to create real money.  The confusion comes from the different ways money is counted.  In M2, deposits count as money.  So if you take $100 and deposit it in the bank, M2 will count the $100 deposit as money, as well as the $100 cash the bank has from the deposit.  So under M2 the money supply has increased by $100, but no real money was created.  Commercial banks can't create real money out of thin air, and they can't loan out money they don't have. The answer is far more simple.   The purchasers of periphery debt have been banks in the periphery. Since these countries don't have a central bank, their private banks were swallowing the national debt since nobody else wanted to touch it.   When the market value of that debt plummets, the banks have massive holes they need to fill on their balance sheets to fulfill capital requirements and solvency. Therefore, the banks themselves need to be injected with liquidity.  Now you can see why its a reiterative problem. Thanks medikit, your answer is 100% correct. Bank of America was forced to accept TARP funds because the US Govt did not want there to be a split between banks who took TARP and those who didn't. Bank of America did NOT need the money, hence they were really unhappy with the strings it came attached with. Rumor has it that they also wanted out of the Countrywide deal after looking at the books, but they were forced by Treasury not to pull out of the deal (a pull-out would signal that things are really bad). The govt offered some deal sweeteners, deal went ahead, then the govt spent the next few years suing Bank of America due to loans originated by Countrywide prior to the acquisition. The CEO ended up having to resign based on the shitshow that was that deal. "Here's some way of thinking about it, and I'm not really sure if it's completely correct, but sometimes we oversimplify when trying to tell a five year old :)  Say there are two people in the world. You and me. We both have $100. A total of $200 in the world.  Suddenly, a wild bank appears. I deposit my $100 in the bank. I still have $100 and you still have $100. Now you want to buy something from me that costs $150. You go to the bank to loan money. The bank has $100 available so gives you $50. You give me $150. Now I have $250 and you are $50 in debt. I deposit the $150 in the bank.  We do this again and again, until I have $1000 on my bank account, and you are $900 in debt. I want to buy a house of $500 and go to my bank, demanding to take out $500. But there is only $200 in the whole world so the bank can only give me $200.  ""Money"" has been created out of thin air, but it's actually you who are in debt. If you go bankrupt, the bank has a big debt it won't get back, and is in deep shit when I come around to demand my money back. At that point governments step in to loan the bank money for cheap, because if the bank fails, I will lose all my pension savings I put into that bank, as well as my companies and a lot of my employees.  And other banks loaned this bank money, so if this bank fails, the other banks will be in the exact same position and will also fail, because then they will also have debts that won't be paid back.  There are regulations minimizing this - i.e. a bank is required to keep a percentage of the amount of money on its accounts, so there's a maximum limit of ""money created""."