Bid, Ask, and the Order You Choose

There's no single 'price' of a stock. There's a price buyers will pay and a price sellers will accept, and the gap between them is a cost you pay without ever seeing a line item for it.

Last verified 2026-07-16

Two prices, and you always get the worse one

The quote you see in an app is usually the last traded price, which is history. What's actually available right now is two numbers: the bid, the highest price a buyer will pay, and the ask, the lowest price a seller will accept.

You buy at the ask and sell at the bid, always. Never the other way round, and never the midpoint between them. So the instant you buy, selling immediately would lose you the difference — you are down by the spread before the stock has moved at all.

The spread is compensation for the market maker who stands ready to trade with you at any moment. It's a fair price for a real service, and it is also a cost that appears on no statement and in no fee schedule. On a heavily traded ETF it might be a penny. On a thin small-cap it can be several percent.

The trade-off you cannot escape

A market order says 'fill me now, at whatever the market offers'. You get certainty of execution and no certainty of price.

A limit order says 'fill me only at this price or better'. You get certainty of price and no certainty of execution — it can sit unfilled indefinitely, and if the stock runs away from your limit you simply never buy it.

There is no order type that guarantees both, and any strategy that seems to offer both is hiding one of the two. Which you should want depends entirely on the situation: for a broad index fund in a calm market the spread is a penny and a market order is fine, while for a thinly traded stock at the open a market order is how people get filled several percent from where they expected.

Stops, and the one that can fail you

A stop order sits dormant until the price touches a trigger, at which point it becomes a market order. People use them to cap a loss without watching the screen.

A stop-limit order does the same thing but becomes a limit order at the trigger. That sounds strictly better and isn't. In a fast decline the price can gap straight past your limit, leaving the order unfilled while the stock keeps falling — you set out to cap a loss and instead capped nothing.

So the two failure modes are opposite. A plain stop will always get you out, potentially at a terrible price during a momentary spike. A stop-limit protects your price and may not get you out at all. Knowing which risk you'd rather carry is the actual decision.