Spread: why it matters more than it seems

The spread — the difference between the buy and sell price — looks like a trifle, but over the long run it's one of a trader's main cost items. Especially for those who trade often and catch short moves. The spread is unnoticeable in a single trade but adds up to a serious sum. Let's look at why it matters more than it seems.

What the spread is

The spread is the difference between the price at which you can buy (the ask) and the price at which you can sell (the bid). When you open a trade, you're immediately at a small loss equal to the spread: to break even, price has to travel that distance in your favor. In essence, the spread is the fee for entering the market, a cost you bear on every trade regardless of whether it turns out profitable.

Why the spread is underestimated

In a single trade the spread seems insignificant — a couple of points against a move of tens of points. But it's paid every time, and over the long run it sums into a large amount. A hundred trades at two points of spread is already two hundred points of cost, 'eaten' quietly and unnoticeably. The spread isn't billed separately, so it's easy to overlook, but it's constantly subtracted from the result. It's precisely this invisibility that makes the spread an insidious cost.

The spread and trading style

The impact of the spread depends sharply on style. For a scalper and a frequent intraday trader catching short moves, the spread is critical: if the target is 10 points and the spread is 2, then a fifth of the potential profit goes to costs before you even start. The shorter the target and the more frequent the trades, the larger the share of profit the spread eats. For a swing and position trader with targets of hundreds of points and rare trades, the spread hardly matters — it's lost against the move. That's why short strategies are especially sensitive to the spread.

How to account for the spread

The spread should be built into your calculations, not ignored. Check the real spread on your pair and broker: it's narrow on majors and notably wider on crosses and exotics. Bear in mind that the spread widens in moments of low liquidity (night, weekends, news, rollover) — a trade at such a moment costs more. Assess the strategy with the spread in mind: short targets should notably exceed the spread, otherwise costs eat the edge. When testing a system, always build in a realistic spread — without it the backtest is overstated.

The practical takeaway

The spread is the difference between the buy and sell price, the fee for entering the market that you bear on every trade. It seems a trifle, but it's paid every time and over the long run sums into a large cost, eating profit quietly and unnoticeably. The spread's impact depends on style: for scalping and frequent trading with short targets it's critical (it can eat a fifth of the target), for swing trading with large targets it hardly matters. Account for the spread in your calculations: check it on your pair and broker, remember its widening in periods of low liquidity, build it into testing, and make sure short targets notably exceed the spread. Understanding that the spread is a constant and underestimated cost helps you choose strategies whose edge survives real trading expenses rather than vanishing under their unnoticed weight.

This material is for educational purposes and is not individual investment advice.