Order Types: Market, Limit & Stop-Loss

What you'll learn

  • How an order book matches buyers and sellers on NSE and BSE
  • The difference between market and limit orders, and when to use each
  • How Stop-Loss (SL) and Stop-Loss Market (SL-M) orders protect you
  • Order validity (DAY, IOC), After-Market Orders (AMO) and GTT orders
  • Product types: Delivery (CNC) vs Intraday (MIS)

You've opened your demat and trading account, picked a stock, and tapped Buy. Your broker app then asks you a few questions: Market or Limit? Delivery or Intraday? Day or IOC? Many beginners skip past these screens and lose money without noticing. In this lesson you'll learn what each choice means so you know exactly what you are asking the exchange to do.

An order is an instruction to your broker, which passes it on to the exchange: "Buy (or sell) this many shares of this company, under these conditions." The conditions are what separate one order type from another.

The Order Book: Where Buyers Meet Sellers

Every listed stock has an order book, a live list of everyone who wants to buy (the bids) and everyone who wants to sell (the asks, also called offers). The exchange's computer matches them automatically on a price–time priority basis: the best price goes first, and if two orders have the same price, the one placed earlier goes first.

Order Book — Sunrise Foods Ltd (fictional)BIDS (Buyers)ASKS (Sellers)QtyPrice ₹Price ₹Qty1,200499.50500.008002,500499.00500.501,900900498.50501.003,2004,000498.00501.501,100Spread = ₹500.00 − ₹499.50 = ₹0.50Best bid and best ask sit at the top The "market depth" screen in your broker app is this order book. Bar length shows the quantity waiting at each price.

The gap between the best bid (highest buyer price) and the best ask (lowest seller price) is called the spread. Large, actively traded stocks like those in the Nifty 50 usually have spreads of just a few paise. Small, illiquid stocks can have spreads of several rupees, and that is a hidden cost every time you trade.

Pro tip: Before placing an order, tap the stock in your app and open Market Depth. It shows the top 5 bids and asks (deeper levels are available on some platforms). If the spread is wide, avoid market orders.

The Two Core Order Types

⚡ Market Order

  • "Buy/sell right now at the best available price"
  • Execution is almost guaranteed
  • Price is not guaranteed
  • Good for very liquid stocks when speed matters
  • Risky in illiquid stocks or fast-moving markets

🎯 Limit Order

  • "Buy/sell only at this price or better"
  • Price is guaranteed (or better)
  • Execution is not guaranteed
  • Your order waits in the order book until matched
  • The default choice for most investors

Market order: what actually happens

Using the order book above, suppose you place a market buy order for 1,000 shares. Only 800 shares are available at ₹500.00, so the exchange fills those, then takes the next 200 from the ₹500.50 level. Your average price becomes:

(800 × ₹500.00 + 200 × ₹500.50) ÷ 1,000 = ₹500.10

The extra ₹0.10 per share is called slippage. Here it is small, but in a thinly traded stock a large market order can "walk up" the book and fill at a much worse price than you expected.

Limit order: you set the price

Now suppose you place a limit buy at ₹499.00 for 1,000 shares. Nobody is selling at ₹499 right now, so your order joins the bid side, behind the 2,500 shares already waiting at ₹499.00 (time priority). It fills only if sellers come down to your price. If the price never drops to ₹499, your order expires unfilled at the end of the day.

When does each order fill? (price path through one day)₹505₹500₹4959:1515:30Limit buy ₹497.50filled hereMarket buy fills instantlyLimit sell ₹505.50 — never reached, expires A market order fills at once. A limit order fills only if the price touches your level.

Stop-Loss Orders: Your Safety Net

A stop-loss is an order that stays dormant until the price hits a trigger price you choose. It is designed to limit your loss if a trade goes against you. Indian brokers offer two kinds:

🛑

SL (Stop-Loss Limit)

You set a trigger price and a limit price. When the trigger is hit, a limit order is sent. You control the worst price, but the order may not fill in a sharp fall.

🚨

SL-M (Stop-Loss Market)

You set only a trigger price. When it's hit, a market order is sent. It is almost certain to fill, but the price can slip below your trigger.

⏰

GTT (Good Till Triggered)

A trigger that stays active for up to a year, not just one day. Brokers commonly use it for long-term stop-losses and price targets on delivery holdings.

Worked example: protecting a ₹500 purchase

You bought 100 shares of Sunrise Foods at ₹500 and decide you won't accept more than about a 5% loss.

  1. Choose your trigger

    5% below ₹500 = ₹475. This is your trigger price.

  2. SL order setup

    Sell 100, trigger ₹475, limit ₹473. If the price falls to ₹475, a limit sell at ₹473 is placed. You will sell at ₹473 or better, but if the price jumps straight past ₹473 (for example, after bad news), you might not sell at all.

  3. SL-M order setup

    Sell 100, trigger ₹475. If it's hit, a market sell is fired immediately. You'll definitely exit, perhaps at ₹474, or ₹468 in a crash.

  4. Know your maximum loss

    With an SL fill at ₹473: (₹500 − ₹473) × 100 = ₹2,700, about 5.4% of ₹50,000.

Anatomy of a Stop-Loss (sell side)₹500 — your buy price₹475 — trigger price (order wakes up)₹473 — limit price (worst you'll accept, SL only)Sell-side SL: limit ≤ trigger. Buy-side SL (for short sellers): limit ≥ trigger. For a sell SL order, the trigger sits above the limit, leaving a small buffer to improve the chance of a fill.
Gap-down risk: If a stock closes at ₹480 and opens the next day at ₹440 after bad results, your ₹475 stop-loss can't save you at ₹475. Your SL-M fills near ₹440, and an SL with a ₹473 limit stays unfilled. A stop-loss limits your loss in normal markets, but no order type removes overnight risk.

Validity, AMO and Product Types

DAY
Valid until market close (3:30 PM), then cancelled
IOC
Immediate or Cancel: fill what you can now, cancel the rest
AMO
After-Market Order: placed after hours, sent at the next open
GTT
Stays live for up to 1 year until triggered

Indian market timings (NSE/BSE equity)

Session Time (IST) What happens
Pre-open 9:00 – 9:15 Orders collected, opening price discovered via call auction
Normal market 9:15 – 15:30 Continuous matching of buy and sell orders
Post-close 15:40 – 16:00 Limited trading at the closing price
AMO window Evening – next morning (broker-specific) Queue orders to be sent when the market opens

Delivery vs Intraday

📦 Delivery (CNC)

  • Shares are credited to your demat account (T+1)
  • Hold for days, months or years
  • Requires full payment
  • Best for investors and beginners

⏱️ Intraday (MIS)

  • Buy and sell on the same day
  • Broker auto-squares off open positions before close
  • Uses leverage (margin), so gains and losses are magnified
  • SEBI studies show most intraday traders lose money
Beginner rule: Stick to Delivery + Limit orders until you understand the market well. If you accidentally choose Intraday (MIS), your shares may be sold automatically at the end of the day, at whatever price the market offers.

Interactive: What Would Happen?

Test your instincts. Read each scenario, decide your answer, then tap to reveal.

📉 Scenario 1: You place a limit buy at ₹480 for a stock trading at ₹500. It falls to ₹482 and bounces back to ₹510. What happened to your order? (Tap to reveal)

Not filled. The price never reached ₹480, so nobody sold to you at your price. A DAY order would be cancelled at the close. That's the trade-off with limit orders: you get price protection but no guarantee of a fill.

⚡ Scenario 2: A small-cap stock shows best ask ₹102 (50 shares), next ₹106 (100 shares), then ₹112 (500 shares). You place a market buy for 400 shares. (Tap to reveal)

Your order walks up the book: 50 × ₹102 + 100 × ₹106 + 250 × ₹112 = ₹5,100 + ₹10,600 + ₹28,000 = ₹43,700.

Average ≈ ₹109.25, about 7% above the ₹102 you saw on screen. This is why you use limit orders in illiquid stocks.

🌙 Scenario 3: It's 9 PM and you read great news about a company. You want to buy first thing tomorrow. What do you do? (Tap to reveal)

Place an AMO (After-Market Order). Use a limit price, because good news often causes a gap-up opening and a market AMO could fill far higher than you expect.

🛑 Scenario 4: You need to exit a falling stock no matter what. SL or SL-M? (Tap to reveal)

SL-M (or a plain market sell if you're exiting right now). Once triggered it becomes a market order, so the exit is near-certain. An SL limit order could be skipped if the price falls through your limit too quickly. Note: some brokers restrict SL-M orders in certain segments, so check what your app offers.

Flip-cards: order jargon

Slippage
The difference between the price you expected and the price you actually got.
Partial fill
Only part of your quantity was executed. The rest stays pending (or is cancelled, for IOC orders).
Circuit limit
The maximum % a stock can move in a day (e.g. 5%, 10%, 20%). At an upper circuit there may be only buyers and no sellers.
Square-off
Closing an open position by taking the opposite trade. Brokers auto square-off intraday positions near the close.

Quick Quiz

1. Which order type guarantees the price but not the execution?

Limit order. It fills only at your price or better.

2. You own shares at ₹200 and set an SL sell with trigger ₹190 and limit ₹188. When is the order sent to the exchange?

When the price trades at or below ₹190 (the trigger). A limit sell at ₹188 is then placed.

3. What does "price–time priority" mean?

The best-priced orders match first. Among orders at the same price, the one placed earliest goes first.

4. Which order type stays active beyond a single trading day for up to a year?

GTT (Good Till Triggered).

5. Why is a market order risky in an illiquid stock?

The spread is wide and the depth is thin, so a market order can fill across several price levels and give you large slippage.

Key Takeaways

  • The order book lists bids and asks, and the exchange matches them by price, then time.
  • Market orders give certainty of execution. Limit orders give certainty of price.
  • Stop-losses (SL and SL-M) cap losses in normal conditions but cannot protect against gap openings.
  • Use AMO for after-hours orders and GTT for long-lasting triggers.
  • Beginners should default to Delivery + Limit orders and always check market depth.