Would it be considered appropriate to use a market order for my very first stock trade?
Difference between a limit and market order is largely a trade-off between price certainty and timing certainty. If you think the security is already well priced, the downside of a limit order is the price may never hit your limit and keep trading away from you. You'll either spend a lot of time amending your order or sitting around wishing you'd amended your order.  The downside of a market order is you don't know the execution price ahead of time. This is typically more of a issue with illiquid instruments where even smaller orders may have price impact. For small trades in more liquid securities your realized price will often resemble the last traded price. Hope that helps. Both have a purpose, and the best tool for the job will depend on your circumstances. If you want to make sure you pay at or below a specific price per share, use a limit order. If you want to buy the stock close to the current price, but aren't price sensitive, use a market order. Market orders are typically not a great idea because if you're buying thousands or tens of thousands of shares this can mean a large swing in cost if the market suddenly changes direction. A few of the answers are spot on but here's another thing to consider: the type of trade. For example, I sometimes day trade stocks with momentum where the stock price is spiking relatively fast. A limit order in this situation may never get filled and you will miss out on the trade. A market order will get you filled but you mostly likely pay more than your limit order. However you are now catching the wave up.  Overall, using a limit or market is relative to your trading style and the type of trade. I always prefer to use a limit buy order. Obvious answer but the limit order should be set at the price that you are willing to pay :). More usefully, if you want a decent chance of the order filling in short notice you should place the order one price tick above the current highest buyer (bid price). As long as high frequency trading remains alive I would advise against ever using market orders, these algorithmic trades can occasionally severely distort the price of a security in a fraction of a second. So if your market order happens to fill in during such a distortion you might end up massively overpaying/underselling.
"Yes, almost always. I trade some of the most illiquid single stock options, and I would be absolutely murdered if I didn't try to work orders between the bid/ask.  When I say illiquid, I mean almost non-existent: ~50 monthly contracts on ALL contracts for a given underlying.  Spreads of 30% or more. The only time you shouldn't try to work an order, in my opinion, is when you think you need to trade immediately (rare), if implied volatility (IV) has moved to such a degree that the market makers (MM) won't hit your order while they're offering fair IV (they'll sometimes come down to meet you at their ""real"" price to get the exchange's liquidity rebate), or if the bid/ask spread is a penny. For illiquid single stock options, you need to be extremely mindful of implied and statistical volatility.  You can't just try to always put your order in the middle.  The MMs will play with the middle to get you to buy at higher IVs and sell at lower. The only way you can hope that an order working below the bid / above the ask will get filled is if a big player overwhelms the MMs' (who are lined up on the bid and ask) current orders and hits yours with one large order.  I've never seen this happen. The only other way is like you said: if the market moves against you, the orders in front of yours disappear, and someone hits your order, but I think that defeats the intent of your question." There is normally a policy at the organisation that would restrict trades or allow trades under certain conditions. This would be in accordance with the current regulations as well as Institutions own ethical standards.  Typical I have seen is that Technology roles are to extent not considered sensitive, ie the employees in this job function normally do not access sensitive data [unless your role is analyst or production support]. An employee in exempt roles are allowed to trade in securities directly with other broker or invest in broad based Mutual Funds or engage a portfolio management services from a reputed organisation. It is irrelevant that your company only deals with amounts > 1 Million, infact if you were to know what stock the one million is going into, you may buy it slightly earlier and when the company places the large order, the stock  typically moves upwards slightly, enough for you to make some good money. That is Not allowed. But its best you get hold of a document that would layout the do' and don't in your organisation. All such organisation are mandated to have a written policy in this regard. I have done this, and the reason is to make sure that I don't run out of money in my account to place the order if there is an unexpected upswing in price. Suppose I have $1000 in my account and I want to buy 10 shares of ABCD that are currently at $99.  If the price doesn't change, then I am all set, but if the price goes up to $101 then I don't have sufficient funds to make the purchase. By placing a limit order at $100 I can ensure that I have enough money to place the order. In general, it is a rather unlikely scenario that it could happen, but placing the limit order is easy to do and it gives me peace of mind. I don't know what you mean about bypassing the queue. The original poster's concern is valid.  Sometimes, market orders do get executed at seemingly ridiculous prices. In addition to Victor's reasons for using a market order, sometimes a seller does not care how low the price is.  For example, after a company goes broke, its stock continues to trade for a while.  This allows shareholders to realize their losses for tax purposes, and allows short-sellers to close out their positions.  A shareholder who is trying to realize a 10 dollar per share loss for tax purposes probably does not care whether he gets 10 cents per share or 0.001 cents per share, so a sell-at-market order makes sense. No, Mark is right, if you place a market order there will always be someone to buy or sell at the market price.  Only if you place a limit order on the price can it not sell or be bought.  Just research on your computer and you will find your answer.  You must be specify about open order or limit order when asking. I assume you're talking about a sell order, not a buy order. When you place a limit sell order, your order is guaranteed to be placed at that price or higher.  If the market is currently trading much higher than the price of your sell order, then your mistakenly low limit order will be essentially a market order, and will be filled at  the current bid price. So the only way this is a problem is if you want to place a limit sell that is much higher than the current market, but mistakenly place a limit lower than the current market. You put in a market order when you want to sell to whomever raises their hand first.  It results in the fastest possible liquidation of your stock. It's appropriate when you need to sell now, regardless of price. An example of when to use it: It's 3:55 PM, the market's going to close in 5 minutes and you need to sell some stocks to make some kind of urgent payment elsewhere.  If instead you have a limit order in place, you might not reach the limit price before the market closes, and you'll still own the stock, which might not be what you want. "I may be underestimating your knowledge of how exchanges work; if so, I apologize.  If not, then I believe the answer is relatively straightforward. Lets say price of a stock at time t1 is 15$ .  There are many types of price that an exchange reports to the public (as discussed below); let's say that you're referring to the most recent trade price.  That is, the last time a trade executed between a willing buyer and a willing seller was at $15.00. Lets say a significant buy order of 1M shares came in to the market. Here I believe might be a misunderstanding on your part.  I think you're assuming that the buy order must necessarily be requesting a price of $15.00 because that was the last published price at time t1.  In fact, orders can request any price they want.  It's totally okay for someone to request to buy at $10.00.  Presumably nobody will want to sell to him, but it's still a perfectly valid buy order. But let's continue under the assumptions that at t1: This makes the bid $14.99 and the ask $15.00.  (NYSE also publishes these prices.) There aren't enough people selling that stock. It's quite rare (in major US equities) for anyone to place a buy order that exceeds the total available shares listed for sale at all prices.  What I think you mean is that 1M is larger than the amount of currently-listed sell requests at the ask of $15.00. So say of the 1M only 100,000 had a matching sell order and others are waiting. So this means that there were exactly 100,000 shares waiting to be sold at the ask of $15.00, and that all other sellers currently in the market told NYSE they were only willing to sell for a price of $15.01 or higher.  If there had been more shares available at $15.00, then NYSE would have matched them. This would be a trigger to the automated system to start increasing the price. Here is another point of misunderstanding, I think.  NYSE's automated system does not invent a new, higher price to publish at this point.  Instead it simply reports the last trade price (still $15.00), and now that all of the willing sellers at $15.00 have been matched, NYSE also publishes the new ask price of $15.01.  It's not that NYSE has decided $15.01 is the new price for the stock; it's that $15.01 is now the lowest price at which anyone (known to NYSE) is willing to sell.  If nobody happened to be interested in selling at $15.01 at t1, but there were people interested in selling at $15.02, then the new published ask would be $15.02 instead of $15.01 -- not because NYSE decided it, but just because those happened to be the facts at the time. Similarly, the new bid is most likely now $15.00, assuming the person who placed the order for 1M shares did not cancel the remaining unmatched 900,000 shares of his/her order.  That is, $15.00 is now the highest price at which anyone (known to NYSE) is willing to buy. How much time does the automated system wait to increment the price, the frequency of the price change and by what percentage to increment etc. So I think the answer to all these questions is that the automated system does none of these things.  It merely publishes information about (a) the last trade price, (b) the price that is currently the lowest price at which anyone has expressed a willingness to sell, and (c) the price that is currently the highest price at which anyone has expressed a willingness to buy. ::edit:: Oh, I forgot to answer your primary question. Can we estimate the impact of a large buy order on the share price? Not only can we estimate the impact, but we can know it explicitly.  Because the exchange publishes information on all the orders it knows about, anyone tracking that information can deduce that (in this example) there were exactly 100,000 shares waiting to be purchased at $15.00.  So if a ""large buy order"" of 1M shares comes in at $15.00, then we know that all of the people waiting to sell at $15.00 will be matched, and the new lowest ask price will be $15.01 (or whatever was the next lowest sell price that the exchange had previously published)." "This is a great question precisely because the answer is so complicated. It means you're starting to think in detail about how orders actually get filled / executed rather than looking at stock prices as a mythical ""the market"". ""The market price"" is a somewhat deceptive term. The price at which bids and asks last crossed & filled is the price that prints. I.e. that is what you see on a market price data feed. ] In reality there is a resting queue of orders at various bids & asks on various exchanges.  (source: Larry Harris. A size of 1 is 1H = 100 shares.) So at first your 1000H order will sweep through the standing queue of fills. Let's say you are trading a low-volume stock. And let's say someone from another brokerage has set a limit order at a ridiculous price. Part of your order may sweep through and part of it get filled at a ridiculously high price. Or maybe either the exchange or your broker / execution mechanism somehow will protect you against the really high fill. (Let's say your broker hired GETCO, who guarantees a certain VWAP.) Also people change their bids & asks in response to what they see others do. Your 1000H size will likely be marked as a human counterparty by certain players. Other players might see that order differently. (Let's say it was a 100 000H size. Maybe people will decide you must know something and decide they want to go the same direction as you rather than take the opportunity to exit. And maybe some super-fast players will weave in and out of the filling process itself.) There is more to it because, what if some of the resting asks are on other venues? What if both you and some of the asks match with someone who uses the same broker as you? Not only do exchange rules come into play, but so do national regulations. tl;dr: You will get filled, with price slippage. If you send in a big buy order, it will sweep through the resting asks but also there are complications." The next day the market opens trading at 10.50, You haven't specified whether you limit order for $10.10 is to buy or sell. When the trading opens next day, it follows the same process of matching the orders. So if you have put a limit order to buy at $10.10 and there is no sell order at that price, your trade will not go through. If you have placed a limit sell order at $10.10 and there is a buyer at or higher price, it would go through. The Open price is the price of the first trade of the day. It definitely depends on the exchange you are trading on. I'm not familiar with Scottrade, but a standard practice is to fulfill limit orders in the order they are placed.   Most of the time, you wouldn't see stocks trade significantly under your bid price, but since penny stocks are very volatile, it's more likely their price could drop quickly past your bid and then return above it while only fulfilling a portion of the orders placed. Example 1. Penny stock priced at $0.12 2. Others place limit orders to buy at $0.10 3. You place limit order to buy at $0.10 4. Stock price drops to $0.07 and some orders are filled (anything $0.07 or higher) based on a first-come first-served basis 5. Due to the increase in purchases of the penny stock, the price rises above $0.10 before your order is filled ***EDIT*** - Adding additional clarification from comment section. A second example If the price drops from $0.12 to $0.07, then orders for all prices from $0.07 and above will start to be filled from the oldest order first. That might mean that the oldest order was a limit buy order for 100 shares at $0.09, and since that is above the current ask price, it will be filled first. The next order might be for 800 shares at $0.07. It's possible for a subset of these to be filled (let's say 400) before the share's price increases from the increased demand. Then, if the price goes above $0.10, your bid will not be filled during that time. "In US public stock markets there is no difference between the actions individual retail traders are ""permitted"" to take and the actions institutional/corporate traders are ""permitted"" to take.  The only difference is the cost of those actions.  For example, if you become a Registered Market Maker on, say, the BATS stock exchange, you'll get some amazing rebates and reduced transaction prices; however, in order to qualify for Registered Market Maker status you have to maintain constant orders in the book for hundreds of equities at significant volumes.  An individual retail trader is certainly permitted to do that, but it's probably too expensive. Algorithmic trading is not the same as automated trading (algorithmic trading can be non-automated, and automated trading can be non-algorithmic), and both can be anywhere from low- to high-frequency.  A low-frequency automated strategy is essentially indistinguishable from a person clicking their mouse several times per day, so: no, from a legal or regulatory perspective there is no special procedure an individual retail trader has to follow before s/he can automate a trading strategy.  (Your broker, on the other hand, may have all sorts of hoops for you to jump through in order to use their automation platform.) Last (but certainly not least) you will almost certainly lose money hand over fist attempting bid-ask scalping as an individual retail trader, whether your approach is algorithmic or not, automated or not.  Why?  Because the only way to succeed at bid-ask scalping is to (a) always be at/near the front of the queue when a price change occurs in your favor, and (b) always cancel your resting orders before they are executed when a price change occurs against you.  Unless your algorithms are smarter than every other algorithm in the industry, an individual retail trader operating through a broker's trading platform cannot react quickly enough to succeed at either of those.  You would have to eschew the broker and buy direct market access to even have a chance, and that's the point at which you're no longer a retail trader. Good luck!" "Yes it is possible, as long as the broker you use allows conditional orders. I use CMC Markets in Australia, and they allow free conditional orders either when initially placing a buy order or after already buying a stock. See the Place New Order box below:  Once you have selected a stock to buy, the number of shares you want to buy and at what price you can place up to 3 conditional orders. The first condition is a ""Place order if..."" conditional order. Here you can place a condition that your buy order will only be placed onto the market if that condition is met first.  Say the stock last traded at $9.80 and you only want to place your order the next day if the stock price moves above the current resistance at $10.00. So you would Place order if Price is at or above $10.00. So if the next day the price moves up to $10 or above your order will be placed onto the market. The second condition is a ""Stop loss"" conditional order. Here you place the price you want to sell at if the price drops to or past your stop loss price. It will only be placed on to the market if your buy order gets traded. So if you wanted to place your stop loss at $9.00, you would type in 9.00 in the box after ""If at or below ?"" and select if you want a limit or market order. The third condition is a ""Take profit"" conditional order. This allows you to take profits if the stock reaches a certain price. Say you wanted to take profits at 50%, that is if the price reached $15.00. So you would type in 15.00 in the box after ""If at or above ?"" and again select if you want a limit or market order. These conditional orders can all be placed at the time you enter your buy order and can be edited or deleted at any time. The broker you use may have a different process for entering conditional orders, and some brokers may have many more conditional orders than these three, so investigate what is out there and if you are confused in how to use the orders with your broker, simply ask them for a demonstration in how to use them." More on a technical note, but the spread on an ETF tends to be worst at market open and near market close. (assuming the ETF constituents are traded on a synchronous basis.) If possible, it's often best to let market makers get up and running before allowing your order to flow into market. If one makes say, $10K/mo, and the company will match the first 5% dollar for dollar, a 10%/mo deposit of $1K/mo will see a $500/mo match. If the employee manages to request 90% get put into the 401(k), after 2 months, he's done.  If the company wished, they could continue the $500/mo match, I agree. They typically don't and in fact, the 'true up' you mention isn't even required, one is fortunate to get it. Many companies that match are going the other way, matching only after the year is over. Why? Why does any company do anything? To save money. I used to make an attempt to divide my deposit over the year to max out the 401(k) in December and get the match real time, not a true up.