Order types and validity

A reader had done the slow work. The company was understood, the price looked fair, and the plan was clear: buy only below a certain price. Then the order went in, the app flashed green, and the position appeared. It looked like every other successful trade - except the average price was well above the line the reader had drawn.

Nothing about the market had changed in those few seconds. The mistake was not in the analysis. It was in the instruction. The reader knew the company; the reader did not know the order.

This is execution plumbing, not stock selection. A careless order can take money before analysis ever gets its turn, and it can do it while the screen looks completely normal.

Most beginner guidance stops at what to buy. It rarely explains how the buying happens. So a reader can spend weeks judging a business and then hand the result to a form they have never read carefully.

An order is not a button that means "get me this share." It is a precise instruction sent to an exchange, and the exchange follows it literally. It does not know what you meant. It knows what you submitted. If the instruction says "fill me now at any available price," that is exactly what you get - even if the available price is much worse than the one on the screen a moment ago.

The habit this module builds is small and protective: before you submit, read the ticket as an instruction, not as a wish. Ask what each field is telling the exchange to do, and whether that matches what you actually decided in a calm moment. The analysis is upstream. This is the last gate before your money leaves, and it deserves the same attention you gave the company.

Every order, on every Indian broker, is the same four fields. Read them in this order every time.

Side. Buy or sell. Obvious, but worth a half-second glance, because a fat-finger reversal here is the most expensive typo in the ticket.

Quantity. How many shares. This interacts with the price field more than beginners expect: a size that is trivial in a deep stock can be most of the day's sellers in a thin one.

Price condition. This is the field that decides the price you actually get, and it is where the reader in the question was hurt. There are three common shapes:

• A market order prioritises execution. It says "fill me now, at whatever price is available." You are guaranteed to trade; you are not guaranteed the price you saw.
• A limit order prioritises price. It says "fill me only at ₹482 or better." You are guaranteed the price condition; you are not guaranteed to trade at all.
• A stop-loss or trigger order stays dormant until the price crosses a level you set, and only then activates - as a market or limit order underneath. It adds a condition before the instruction becomes live.

Validity. The time instruction. Order validity controls how long the order stays alive if it does not fill immediately: Day (dies at market close), IOC (immediate-or-cancel - fill what you can right now, cancel the rest), or a GTT-style standing instruction that waits across days. A limit order with the wrong validity can quietly expire before it ever gets its price.

The reader in the question was not unlucky. They were literal. Here is the arithmetic the exchange ran on their behalf. [illustrative]

The last traded price was ₹482. That number is a record of one past trade - a single earlier transaction - not an inventory of shares waiting at ₹482. To fill a market buy for 500 shares, the exchange looks at the market depth: the live queue of sellers. Suppose the book held 80 shares at ₹483, 120 at ₹490, 150 at ₹502, and the rest only near ₹525. A market order does not wait or negotiate. It takes the cheapest available, then the next, then the next, until 500 shares are bought - landing at an average around ₹511.

That ₹29-a-share gap between the screen and the fill is slippage, and in a thin book it is not a rare accident; it is the predictable behaviour of the instruction that was sent. Every rupee of that gap is a cost, whether or not the app ever named it as one. A limit order at ₹482 would have refused to climb the book - filling the 80 cheap shares and then simply waiting, or expiring, rather than paying ₹525.

So the reading is not "the market moved against me." The reading is "I sent an instruction that fills at any price, into a book where any price was expensive."

A reader wants to buy 500 shares of a small-cap they have researched. The screen shows a last traded price of ₹482. They open the ticket. Before submitting, run the audit.

The evidence in front of them: the last traded price is visible; the depth is thin, with only a handful of sellers near ₹482; the ticket defaults to a market order; and a quick mental fill suggests the real average could be several rupees higher.

The read: the last traded price is not the executable price for this quantity. The number on the screen belongs to a past trade of a smaller size. Nothing here justifies a market order.

The repair: check the depth first - how many shares actually sit near the price you want. Switch the price condition to a limit at the price you decided in advance. Read the validity so the order does not expire before it can work. Only then submit. If any field is unclear, the correct move is to stop and edit, not to trust the default. The safest order is the one whose every field you have actually read, against the depth that will fill it.

When it does fill, the contract note - the broker's official record of the trade - is where you confirm the price and charges you actually got. The ticket is the instruction; the contract note is the receipt. Module 005 reads that receipt in full.

Knowing your order types does not create liquidity. If a stock genuinely has few buyers and sellers, no clever instruction conjures shares at a good price out of an empty book. A limit order protects you from paying a bad price; it cannot force a trade that the market is not offering. Sometimes the honest outcome is that the order does not fill, and that is the instruction working, not failing.

This module also cannot tell you whether to buy the company or what price is fair. Those are upstream decisions. Order craft only makes sure that a decision you already made is carried out faithfully instead of being quietly damaged on the way to the exchange.

And it cannot remove market risk. A perfectly placed limit order into a wonderful fill can still be a holding that falls tomorrow. Clean execution protects the decision, not the outcome.

1. Treating the last traded price as the executable price. It is the price of one past trade, not a queue of shares waiting for your quantity. This single confusion is behind most surprise fills.

2. Accepting the ticket's default price condition. The app chose it; you did not. A default market order in a thin stock is the exact trap in this module.

3. Ignoring depth before a market order. The order type is only as safe as the book behind it. The same market order is calm in a deep stock and dangerous in a thin one.

4. Setting a limit price but not reading validity. A good price with the wrong time instruction can expire unfilled, and the reader never learns why nothing happened.

5. Confusing "the trade happened" with "the trade was correct." A green confirmation means the instruction executed, not that it executed the way you intended.