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STOPS, STOP-LIMITS, AND THE FINE PRINT

Lesson 19 of 72 · 6 min read · Stage 2 · Brokers, Accounts & Orders · Updated Oct 21, 2026
STAGE 2 — Brokers, Accounts & Orders · Prerequisite: MARKET VS LIMIT — TWO DOORS INTO THE MARKET
TL;DR
  • A stop order sleeps until price touches its trigger, then becomes a market order. It guarantees an exit attempt — not an exit price. Gap through your stop and you fill at the open's price, not at your stop.
  • A stop-limit order triggers into a limit order instead: your price is protected, your exit is not. Gap through the limit and you still own the position, falling.
  • Time in force: DAY orders die at the close; GTC orders live on — dangerous when forgotten. And in a cash account, selling a purchase before the funds that paid for it settle is a good faith violation: three in 12 months restricts the account for 90 days.

Stops are triggers, not floors; time-in-force decides when an order dies; and the cash account has a tripwire with a name: the good faith violation. A stop order is a tripwire wired to a shout: when the wire breaks, you shout ‘sell at market!’ into whatever chaos broke it. A stop-limit is a tripwire wired to a card: ‘sell — but not below my price.’ If the room has already emptied past your price, the card is never read, and you're still standing there holding the thing you meant to sell.

Gap diagram · diagram · One overnight gap, three orders: what each one actually does at the open. The price path is the lesson's illustrative example; the mechanics are the real rules.

THE TAKEAWAYS

  • Stop-market mechanics: trigger price trades → market order fires. Its job is to get you out; in a gap or a crash its fill is the next available price — Lesson 4's Flash Crash filled stops at stub quotes. This course therefore sizes positions so a stop is a convenience, never a lifeline (Stage 4).
  • Stop-limit mechanics: trigger → limit order at your limit price. A calm slide fills near the stop; a gap jumps clean over the limit and leaves you unfilled. Decide in advance which failure you prefer, because you are choosing one: a bad fill, or no fill.
  • Time in force: DAY expires at today's close (4:00pm ET). GTC — ‘good till cancelled’ — keeps working across days until it fills, you cancel it, or your broker's cap on GTC order length expires it (caps vary by broker; check yours). Never leave a GTC order sitting on an options position through earnings or big news.
  • Good faith violation (cash accounts, Regulation T): buy with unsettled funds — say, this morning's sale proceeds, which settle T+1 — and sell that purchase before the original funds settle. Brokers must track these: three within 12 months restricts the account to buying with settled cash only, for 90 days. Worse is free riding — selling before ever paying for the purchase — which brings the 90-day restriction immediately.
RUSTY’S RULE
A stop is a trigger, not a floor — no order type can sell at a price that never traded. Your real floor is position size (Stage 4); orders are just how the exit gets delivered.

WORKED EXAMPLE — STEP BY STEP

  1. The lesson's example — round numbers, real mechanics. You hold a stock bought at 760. Before bed you set protection at 740 and sleep. The graphic draws the night that follows.
  2. Overnight, bad news lands. The stock opens at 712 — it never trades at 740 at all. If your protection was a stop-market at 740, it triggers at the open and becomes a market order: it fills near 712, the first available price. The stop did its job — you are out — at a price $28 below the number on the ticket.
  3. Same night, a stop-limit: trigger 740, limit 740. It triggers too, but the resulting limit order demands 740 or better. The market is at 712 and falling. No fill. By lunch the stock is 690 and you still own it — the protection protected your price by refusing your exit.
  4. Neither tool failed. Both did exactly what their names say, and the beginner's error was expecting a stop to be a floor. A floor requires a price that actually trades; on a gap, the price you named simply never exists.
  5. The cash-account version of the same carelessness: Monday you sell a position (settles Tuesday). Monday afternoon you buy a new one with the proceeds and sell it Monday evening. When you sold it, the purchase had never been paid for with settled money — good faith violation, strike one of three within 12 months.
THE TRAP — THE GTC YOU FORGOT

A GTC limit buy placed ‘just in case’ at an ambitious price, then forgotten for three weeks. News breaks, the stock falls through your price on its way somewhere much worse, and the old order cheerfully fills — you now own a falling position you no longer want, bought by an instruction written by a previous version of your plan. The fix is a habit, not a setting: review working orders like positions, every session, and let DAY orders die their natural death unless you consciously renew them.

WHY THIS COURSE BARELY USES STOPS ON OPTIONS

Option prices are computed from the underlying, jumpy, and quoted wide — a stop keyed to an option's own prints can trigger on one momentarily wide quote or a single odd trade, then convert to a market order into the widest spread of the day. Professionals who ‘stop’ options usually key the trigger to the underlying stock's price, or run exits as an alert plus a limit order placed by hand. This course's exits (Stage 8) are written in advance and executed with alerts and limit orders. The stop order stays what it is: a shares tool, used with its gap behaviour fully understood — never a magic floor under an option.

COMMON BEGINNER MISTAKES

  • Believing a stop guarantees the stop price. It guarantees a market order; the fill is the market's choice.
  • Placing a stop-limit and never checking whether it filled. An unfilled stop-limit is a hope with paperwork.
  • Leaving GTC orders working through earnings, holidays — and your own vacation.
  • Selling a same-day purchase in a cash account before the funding sale settles: one good faith violation; two more inside 12 months and the account is settled-cash-only for 90 days.

CHECK YOURSELF

Q1. Your stop is at 740. Bad news; the stock opens at 712. A stop-market order fills…

Q2. Same gap, a stop-limit at trigger 740 / limit 740. The result:

Q3. Three good faith violations within 12 months in a cash account means…

DO IT — TRIGGER BOTH STOPS ON PAPER

In your paper account, buy 1 share of SPY on paper, twice (two separate paper positions). Protect the first with a stop-market about 2% below the current price; protect the second with a stop-limit, same trigger, limit equal to the trigger. Over the next sessions, journal what each does — which fills, when, and at what price versus its trigger. Then cancel everything still working. Stage 3 teaches the chart you'll aim these at; this stage is about knowing what the tools actually do.

Download this lesson’s cheat sheet (PDF)

STAGE 2 — BROKERS, ACCOUNTS & ORDERS — ALL 6 LESSONS

  1. 15WHAT A BROKER ACTUALLY DOES5 min read
  2. 16CASH VS MARGIN — AND THE ONE-DAY SETTLE5 min read
  3. 17MARGIN, HONESTLY — BORROWED MONEY, REAL TEETH6 min read
  4. 18MARKET VS LIMIT — TWO DOORS INTO THE MARKET5 min read
  5. 19STOPS, STOP-LIMITS, AND THE FINE PRINTYOU ARE HERE
  6. 20READING A QUOTE — AND WHAT THE ROUND TRIP COSTS6 min read