Limit Order
A limit order instructs a broker to buy a stock at or below a stated price, or to sell at or above it. Execution price is guaranteed; execution itself is not.
If the market never reaches the limit, the order sits unfilled. That trade-off, price certainty against fill certainty, is the entire decision.
The math
Suppose a stock is quoted at $62.30 bid, $62.40 ask, and an investor wants 500 shares. A market order fills at roughly $62.40 for $31,200.
A limit order at $62.00 fills only if sellers come down: if it executes, the position costs $31,000, a $200 saving. Now flip the outcome.
The stock never touches $62.00, climbs to $75 over the next year, and the order expires. The investor saved nothing and missed $6,300 of gain chasing a $200 discount.
| Market order | Limit at $62.00 | |
|---|---|---|
| Fill price | ~$62.40 | $62.00, if reached |
| Cost of 500 shares | $31,200 | $31,000 |
| Stock climbs to $75 | Gain captured | $6,300 missed |
The trap
Anchoring on a round number just below the market is the classic error. The order rests a few cents out of reach, the thesis plays out without the position, and the investor quietly repurchases higher or not at all.
Research on retail limit orders shows they fill most reliably when the stock is falling, which means the fills cluster exactly when new negative information has arrived. The bargain fills are adversely selected.
The move
For a buy-and-hold investor, the practical tool is the marketable limit order: set the limit a few cents above the current ask when buying. It executes immediately like a market order but caps the damage if the quote moves or the book is thin.
Reserve resting limits well below the market for names already researched and sized, treated as standing offers rather than predictions. And when the analysis says a business is worth $90 and it trades at $62, arguing over the last 40 cents is a rounding error on the actual opportunity.
Reference: SEC investor.gov