Can individuals day-trade stocks using High-Frequency Trading (HFT)?
The answer is to your question is somewhat complicated. You will be unable to compete with the firms traditionally associated with High Frequency Trading in any of their strategies. Most of these strategies which involve marketing making, latency arbitrage, and rebate collection. The amount of engineering required to build the infrastructure required to run this at scale makes it something which can only be undertaken by a team of highly skilled engineers. Indeed, the advantage of firms competing in this space such as TradeBot, TradeWorx, and Getco comes from this infrastructure as most of the strategies that are developed are necessarily simple due to the latency requirements. Now if you expand the definition of HFT to include all computerized automated trading you most certainly can build strategies that are profitable. It is not something that you probably want to tackle on your own but I know of a couple of people that did go it alone successfully for a couple of years before joining an established firm to run a book for them. In order to be successful you will most likely need to develop a unique strategies. The good news is because that you are trying to deploy a very tiny amount of capital you can engage in trades that larger firms would not because the strategies cannot hold enough capital relative to the firms capital base.  I am the co-founder of a small trading firm that successfully trades the US Equities and Equity Derivatives markets. A couple of things to note is that if you want to do this you should consider building a real business. Having some more smart brains around you will help. You don't need exchange colocation for all strategies. Many firms, including ours, colocate in a data center that simply has proximity to the exchanges data centers. You will need to keep things simple to be effective.  Don't except all the group think that this is impossible. It is possible although as a single individual it will be more difficult. It will require long, long hours as you climb the algorithmic trading learning curve. Good luck. Nobody is going to stop you if you want to try that. But you should keep in mind that you have to invest a lot in getting the best hardware you can lay your hands on, best fail-safe connectivity to the exchanges, best trading algorithms and software that money can buy and loads of other stuff. This all needs quite a big amount of upfront investment without guaranteeing returns. That is why you see institutions with deep pockets i.e. banks and trading firms only involve themselves in HFT. "Yes you can, but to do so successfully, you need lots of money. You also need to be able to meet the criteria for being classified as a ""professional trader"" by the IRS. (If not, you'll be buried in paperwork.) The fact that you're asking about it here probably means that you do not have enough money to succeed at HFT." I just finished a high frequency trading project. Individuals can do it, but you need a lot of capital. You can get a managed server in Times Square for $1500/month, giving you access to 90% of the US exchanges that matter, their data farms are within 3 milliseconds of distance (latency). You can also get more servers in the same building as the exchanges, if you know where to look ;) thats all I can divulge good luck
It's not enough just to check if your order doesn't exceed 10% of the 20 day average volume. I'll quote from my last answer about NSCC illiquid charges: You may still be assessed a fee for trading OTC stocks even if your account doesn't meet the criteria because these restrictions are applied at the level of the clearing firm, not the individual client. This means that if other investors with your broker, or even at another broker that happens to use the same clearing firm, purchase more than 5 million shares in an individual OTC stock at the same time, all of your accounts may face fees, even though individually, you don't exceed the limits. The NSCC issues a charge to the clearing firm if in aggregate, their orders exceed the limits, and the clearing firm usually passes these charges on to the broker(s) that placed the orders. Your broker may or may not pass the charges through to you; they may simply charge you significantly higher commissions for trading OTC securities and use those to cover the charges.  Since checking how the volume of your orders compares to the average past volume, ask your broker about their policies on trading OTC stocks. They may tell you that you won't face illiquid charges because the higher cost of commissions covers these, or they may give you specifics on how to verify that your orders won't incur such charges. Only your broker can answer this with certainty. "What if everyone decided to sell all the shares at a given moment, let's say when the stock is trading at $40? It would fall to the lowest bid price, which could be $0.01 if someone had that bid in place. Here is an example which I happened to find online:  Notice there are orders to buy at half the market price and lower... probably all the way down to pennies.  If there were enough selling activity to fill all of those bids you see, then the market price would be the lowest bid on the screen.  Alternatively, the bid orders could be pulled (cancelled), which would also let the price free-fall to the lowest bid even if there were few actual sellers. Bid-stuffing is what HFT (high frequency trading) algorithms sometimes do, which some say caused the Flash Crash of May 2010.  The computers ""stuff"" bids into the order book, making it look like there is demand in order to trigger a market reaction, then they pull the bids to make the market fall.  This sort of thing happens all the time and Nanex documents it http://www.nanex.net/FlashCrash/OngoingResearch.html Quote stuffing defined: http://www.investopedia.com/terms/q/quote-stuffing.asp I remember the day of the Flash Crash very well.  I found this video on youtube of CNBC at that time.  Watch from the 5:00 min mark on the video as Jim Crammer talks about PG easily not being worth the price of the market at that time.  He said ""Who cares?"", ""Its not a real price"", ""$49.25 bid for 50,000 shares if I were at my hedge fund.""  http://www.youtube.com/watch?v=86g4_w4j3jU You can value a stock how you want, but its only actually worth what someone will give you for it. More examples: Anadarko Petroleum, which as we noted in today's EOD post, lost $45 billion in market cap in 45 milliseconds (a collapse rate of $1 billion per millisecond), flash crashing from $90 all the way to an (allegedly illegal) stub quote of $0.01. http://www.zerohedge.com/news/2013-05-17/how-last-second-flash-crash-pushed-sp-500-1667-1666 How 10,000 Contracts Crashed The Market: A Visual Deconstruction Of Last Night's E-Mini Flash Crash http://www.zerohedge.com/news/2012-12-21/how-10000-contracts-crashed-market-visual-deconstruction-last-nights-e-mini-flash-cr Symantec Flash-Crash Destroys Over $1.5 Billion In Less Than A Second http://www.zerohedge.com/news/2013-04-30/symantec-flash-crash-destroys-over-15-billion-less-second This sort of thing happens so often, I don't pay much attention anymore." I disagree strongly with the other two answers posted thus far. HFT are not just liquidity providers (in fact that claim is completely bogus, considering liquidity evaporates whenever the market is falling). HFT are not just scalping for pennies, they are also trading based on trends and news releases. So you end up having imperfect algorithms, not humans, deciding the price of almost every security being traded. These algorithms data mine for news releases or they look for and make correlations, even when none exist.  The result is that every asset traded using HFT is mispriced. This happens in a variety of ways. Algos will react to the same news event if it has multiple sources (Ive seen stocks soar when week old news was re-released), algos will react to fake news posted on Twitter, and algos will correlate S&P to other indexes such as VIX or currencies. About 2 years ago the S&P was strongly correlated with EURJPY. In other words, the American stock market was completely dependent on the exchange rate of two currencies on completely different continents. In other words, no one knows the true value of stocks anymore because the free market hasnt existed in over 5 years. "n1. go to tradeworx.com and you can read some papers.  2. Revenues of hft have gone down substantially. About 15 years ago the total market was around 7 billion, it has dropped to 1 billion this year.  3. ""no goods or valuable services are produced.- That is false. hft provides liquidity and low spreads. There is a reason why you can buy or sell a share of a stock and the spread is 1 penny. One of the main reasons to go public is to have the secondary market liquid.   There is a reason you can instantly sell or buy a stock... Do you realize you used to have to actually call your broker and he had to negotiate an order on the floor? hft makes the markets more efficient. The average person can sign up an online acct and trade/invest for basically nothing. Why do you think that is?  finally who are you to say how I can or can not allocate my money. If I develop my own strategy that trades every second why can't I?" "Traditional brokers There are tons of players in this market, especially in USA. You have traditional brokers, brokers tied to your bank and a bunch of startups. The easiest is probably a broker tied to your bank, because you probably don't have to wait to fund your brokerage account and can start trading immediately. Often the older/traditional brokers don't have very intuitive interfaces, it's the startups who do a better job at this. But honestly it doesn't really matter, because you can use reporting services that are different from the services you use to execute your trades. Meaning that you only use the interface of your broker to execute trades (buy or sell), and use third party services to monitor your holdings. Monitoring services: Google Finance, Yahoo Finance, Sigfig, Morningstar,... are services allowing you to monitor your holdings. But you can't execute trades with them. Start-ups: Then there are a bunch of startups that offer investment services besides the traditional brokers. Start-up > Robinhood The most ambitious one is Robinhood, which offers the same service as a traditional broker, but completely free (most of the traditional brokers charge a flat fee and/or percentage when buying/selling hodlings) and with an intuitive interface. They're mobile first, but announced they will be launching their service on the web soon. Start-up > Acorns Another popular, mobile-first start-up is Acorns. They offer a lazy-investing service which rounds your everyday purchases and uses the change to invest. It's great when investing is not on your mind, but you still want to invest without realizing it. Start-ups > Robo-advisors Robo-advisors auto-invest your money across a bunch of funds picked based on your risk profile. Because the robo-advisers are fairly new, they often have the most intuitive interfaces. These robo-advisors often don't allow you to pick individual holdings, so these services are best when you want to passively invest. Meaning you don't want to look at it very often, and let them do the investing for you. There are tons of robo-advisor start-ups: Betterment, Wealthfront, Personal Capital, Sigfig, FutureAdvisor,... Also bigger parties jumped on this trend with their offerings: Schwab Intelligent Portfolios, Ally Managed Portfolio, Vanguard Personal Advisor, etc. Summary: It's fun to pick individual stocks, but if you start out it can be overwhelming. Robinhood is probably the best start, they have reduced functionality, but gets you going with an attractive interface. But soon you'll realize it's extremely hard to beat the market. Meaning that hand-picking stocks statistically gives you a worse return than just buying into the general stock market (like S&P500). So you can decide to just buy one fund with a traditional broker that covers the general stock market. Or you can decide to try out one of the many robo-advisors. They haven't been around that long, so it's hard to tell how effective these are and whether they beat the market. If you're young, and you believe in start-ups (who often try to challenge the traditional players), try out one of the robo-advisors. If you want to play a bit and are addicted to your smartphone, try out Robinhood. If you are addicted to your phone, but don't want to check up on your investments all the time, go for Acorns. Of course you can combine all these. Lastly, there are tons of cryptocurrencies which might give you a large return. Tons of startups offer intuitive interfaces to trade cryptocurrencies like Coinbase, Gemini, Kraken. But beware, there is a lot of risk involved in trading cryptocurrencies, it's completely unregulated etc. But definitely check them out. Oh, and you can also invest by giving out loans through LendingClub, Prosper etc. Who can you trust? Above gives you an overview of your options intermingled with some reasoning. But regarding your question ""who can I trust"" in terms of advice, it's up to yourself. Most traditional broker services don't give you any advice at all, you're on your own. Robo-advisors don't give you advice either, but let their proprietary algorithm do the job. Are these reliable? Nobody can tell, they haven't been around long enough, and they need to go through a bear market (a crash) to see how they respond during rough times. Some robo-advisors offer you personal consultancy (I believe Sigfig and PersonalCapital) does this (limited to a few hours per year). But obviously they'll try to promote their robo-advisor services." "The T+3 ""rule"" relates only to accounting and not to trading.  It does not prevent you from day trading.  It simply means that the postings in you cash account will not appear until three business days after you have executed a trade.  When you execute a trade and the order has been filled, you have all of the information you need to know the cash amounts that will hit your account three business days later. In a cash account, cash postings that arise from trading are treated as unsettled (for three days), but this does not mean that these funds are available for further trading.  If you have $25,000 in your account on day 1, this does not mean that you will be able to trade more than $25,000 because your cash account has not yet been debited.  Most cash accounts will include an item detailing ""Cash available for trading"".  This will net out any unsettled business transacted. For example, if you have a cash account balance of $25,000 on day one, and on the same day you purchase $10,000 worth of shares, then pending settlement in your cash account you will only have $15,000 ""Cash available for trading"". Similarly, if you have a cash balance of $25,000 on day one, and on the same day you ""day trade"", purchasing $15,000 and selling $10,000 worth of shares, then you will have the net of $20,000 ""Cash available for trading"" ($20,000 = $25,000 - $15,000 + $10,000). If by ""prop account"" you mean an account where you give discretion to a broker to trade on your behalf, then I think the issues of accounting will be the least of your worries.  You will need to be worried about not being fleeced out of your hard earned savings by someone far more interested in lining their own pockets than making money for you." Pretty sure the major retail brokerage firms require 25k to daytrade.    Read the top comment. You will get crushed by commissions. There are commission free ETFs, but that's not the kind of investing you seem to want to learn about. The problem you're talking about can be handled the same way now until better alternatives appear. I'm simply talking about improving the existing infrastructure to carry out these trades. Instead of holding a number on charles schwab account, you hold a token which is the same as a stock certificate of ownership.